# Pathnames für CLISP
# Bruno Haible 1990-2001
# Logical Pathnames: Marcus Daniels 16.9.1994
# ANSI compliance, bugs: Sam Steingold 1999-2001

#include "lispbibl.c"

#ifdef HAVE_DISASSEMBLER
  #include <string.h> # declares strlen()
  #ifdef RETSTRLENTYPE # unless strlen() is a macro
    extern_C RETSTRLENTYPE strlen (STRLEN_CONST char* s);
  #endif
#endif

#ifdef UNIX_LINUX
  #include <stdio.h> # declares sprintf()
#endif

# enable the following #define to debug pathname translations
# setting DEBUG_TRANSLATE_PATHNAME to a larger value results in more output
# WARNING: PRIN1 can trigger GC! BEWARE!
/* #define DEBUG_TRANSLATE_PATHNAME 1 */
#if DEBUG_TRANSLATE_PATHNAME
#define DOUT(label,object) \
 printf(#label #object ": ");pushSTACK(object);funcall(L(prin1),1);printf("\n")
#else
#define DOUT(l,o)
#endif
#if DEBUG_TRANSLATE_PATHNAME > 1
local void show_stack (const char* title,int nn) {
  int ii;
  printf("\n * %s:\n",title);
  for (ii=0; ii<=nn; ii++) {
    printf("   stack[%d]: ",ii);
    pushSTACK(STACK_(ii));
    funcall(L(prin1),1);
    printf("\n");
  }
}
#define SHOW_STACK(t,n) show_stack(t,n)
#else
#define SHOW_STACK(t,n)
#endif

# =============================================================================
#                       Low level functions

# UP: Tests whether a pathname is possibly a symlink.
# possible_symlink(path)
#ifdef UNIX_LINUX
  local inline bool possible_symlink (const char* path);
  local inline bool possible_symlink(path)
    var const char* path;
    {
      # In Linux 2.0.35, /proc/<pid>/{cwd,exe,root} and /proc/<pid>/fd/<n>
      # are symlinks pointing to void. Treat them like non-symlinks, in order
      # to avoid errors.
      if (path[0]=='/'
          && path[1]=='p' && path[2]=='r' && path[3]=='o' && path[4]=='c'
          && path[5]=='/'
          && (path[6]>='0' && path[6]<='9')
         )
        return false;
      return true;
    }
#else
  #define possible_symlink(path)  true
#endif

#ifdef UNIX_LINUX
  # The Linux /proc filesystem has some symlinks whose readlink value is
  # zero-terminated: /proc/self in Linux 2.0.35, /proc/<pid>/fd/<n> in
  # Linux 2.2.2. Remove this extraneous trailing zero byte.
  local inline int my_readlink (const char* path, char* buf, size_t bufsiz);
  local inline int my_readlink(path,buf,bufsiz)
    var const char* path;
    var char* buf;
    var size_t bufsiz;
    {
      var int linklen = readlink(path,buf,bufsiz);
      if (linklen > 0 && buf[linklen-1] == '\0')
        linklen--;
      return linklen;
    }
  #define readlink  my_readlink
#endif

#ifdef UNIX
  # Library-Funktion realpath implementieren:
  # [Copyright: SUN Microsystems, B. Haible]
  # TITLE
  #   REALPATH(3)
  # SYNOPSIS
  #   char* realpath (const char* path, char resolved_path[MAXPATHLEN]);
  # DESCRIPTION
  #   realpath() expands all symbolic links  and  resolves  refer-
  #   ences  to '/./', '/../' and extra '/' characters in the null
  #   terminated string named by path and stores the canonicalized
  #   absolute pathname in the buffer named by resolved_path.  The
  #   resulting path will have no symbolic links  components,  nor
  #   any '/./' or '/../' components.
  # RETURN VALUES
  #   realpath() returns a pointer to the  resolved_path  on  suc-
  #   cess.   On  failure, it returns NULL, sets errno to indicate
  #   the error, and places in resolved_path the absolute pathname
  #   of the path component which could not be resolved.
  #define realpath  my_realpath  # Consensys deklariert realpath() bereits...
  local char* realpath (const char* path, char* resolved_path);
  # Methode: benutze getwd und readlink.
  local char* realpath(path,resolved_path)
    var const char* path;
    var char* resolved_path;
    {
      var char mypath[MAXPATHLEN];
      var int symlinkcount = 0; # Anzahl bisher aufgetretener symbolischer Links
      var char* resolved_limit = &resolved_path[MAXPATHLEN-1];
      # Gültige Pointer sind die mit resolved_path <= ptr <= resolved_limit.
      # In *resolved_limit darf höchstens noch ein Nullbyte stehen.
      # (Analog mit mypath.)
      var char* resolve_start;
      {
        var char* resolved_ptr = resolved_path; # (bleibt stets <= resolved_limit)
        # evtl. Working-Directory benutzen:
        if (!(path[0]=='/')) { # kein absoluter Pathname ?
          if (getwd(resolved_path) == NULL)
            return NULL;
          resolved_ptr = resolved_path;
          while (*resolved_ptr) {
            resolved_ptr++;
          }
          if (resolved_ptr < resolved_limit) {
            *resolved_ptr++ = '/';
          }
          resolve_start = resolved_ptr;
        } else {
          resolve_start = resolved_ptr = &resolved_path[0];
        }
        # Dann path selber einkopieren:
        var const char* path_ptr = path;
        while ((resolved_ptr < resolved_limit) && *path_ptr) {
          *resolved_ptr++ = *path_ptr++;
        }
        # Mit '/' und einem Nullbyte abschließen:
        if (resolved_ptr < resolved_limit) {
          *resolved_ptr++ = '/';
        }
        *resolved_ptr = 0;
      }
      # Los geht's nun in resolved_path ab resolve_start.
      var char* from_ptr = resolve_start;
      var char* to_ptr = resolve_start;
      while ((to_ptr < resolved_limit) && (*from_ptr)) {
        # Bis hierher hat der Pfad in  resolved_path[0]...to_ptr[-1]
        # die Gestalt '/subdir1/subdir2/.../txt',
        # wobei 'txt' evtl. leer, aber kein subdir leer.
        var char next = *from_ptr++; *to_ptr++ = next;
        if ((next == '/') && (to_ptr > resolved_path+1)) {
          # to_ptr[-1]='/'  ->  Directory ...to_ptr[-2] auflösen:
          var char* last_subdir_end = &to_ptr[-2];
          switch (*last_subdir_end) {
            case '/':
              #ifdef PATHNAME_UNIX_UNC
              if (to_ptr > resolved_path+2)
              #endif
                # '//' wird zu '/' vereinfacht:
                to_ptr--;
              break;
            case '.':
              {
                var char* last_subdir_ptr = &last_subdir_end[-1];
                if (to_ptr > resolved_path+2) {
                  if (*last_subdir_ptr == '.') {
                    if ((to_ptr > resolved_path+4) && (*--last_subdir_ptr == '/')) {
                      # letztes subdir war '/../'
                      # Dafür das subdir davor entfernen:
                      while ((last_subdir_ptr > resolved_path) && !(*--last_subdir_ptr == '/'));
                      to_ptr = last_subdir_ptr+1;
                    }
                  } elif (*last_subdir_ptr == '/') {
                    # letztes subdir war '/./'
                    # entfernen:
                    to_ptr = last_subdir_end;
                  }
                }
              }
              break;
            default:
              # nach einem normalen subdir
              #ifdef HAVE_READLINK
              if (possible_symlink(resolved_path)) {
                # symbolischen Link lesen:
                to_ptr[-1]=0; # '/' durch 0 ersetzen
                #ifdef UNIX_CYGWIN32 # needed for Win95 only
                # readlink() doesn't work right on NFS mounted directories
                # (it returns -1,ENOENT or -1,EIO).
                # So check for a directory first.
                var struct stat statbuf;
                if (lstat(resolved_path,&statbuf) < 0)
                  return NULL; # Fehler
                if (S_ISDIR(statbuf.st_mode)) {
                  # Verzeichnis, kein symbolisches Link
                  to_ptr[-1] = '/'; # wieder den '/' eintragen
                } else
                #endif
                {
                  var int linklen = readlink(resolved_path,mypath,sizeof(mypath)-1);
                  if (linklen >=0) {
                    # war ein symbolisches Link
                    if (++symlinkcount > MAXSYMLINKS) {
                      errno = ELOOP_VALUE; return NULL;
                    }
                    # noch aufzulösenden path-Anteil an den Link-Inhalt anhängen:
                    {
                      var char* mypath_ptr = &mypath[linklen]; # ab hier ist Platz
                      var char* mypath_limit = &mypath[MAXPATHLEN-1]; # bis hierher
                      if (mypath_ptr < mypath_limit) { *mypath_ptr++ = '/'; } # erst ein '/' anhängen
                      # dann den Rest:
                      while ((mypath_ptr <= mypath_limit) && (*mypath_ptr = *from_ptr++)) { mypath_ptr++; }
                      *mypath_ptr = 0; # und mit 0 abschließen
                    }
                    # Dies ersetzt bzw. ergänzt den path:
                    if (mypath[0] == '/') {
                      # ersetzt den path:
                      from_ptr = &mypath[0]; to_ptr = resolved_path;
                      while ((*to_ptr++ = *from_ptr++));
                      from_ptr = resolved_path;
                    } else {
                      # ergänzt den path:
                      # Linknamen streichen. Dazu bis zum letzten '/' suchen:
                      {
                        var char* ptr = &to_ptr[-1];
                        while ((ptr > resolved_path) && !(ptr[-1] == '/')) { ptr--; }
                        from_ptr = ptr;
                      }
                      {
                        var char* mypath_ptr = &mypath[0]; to_ptr = from_ptr;
                        while ((to_ptr <= resolved_limit) && (*to_ptr++ = *mypath_ptr++));
                      }
                    }
                    to_ptr = from_ptr;
                  } else {
                    #if defined(UNIX_IRIX)
                    if ((errno == EINVAL) || (errno == ENXIO))
                    #elif defined(UNIX_MINT)
                    if ((errno == EINVAL) || (errno == EACCESS))
                    #elif defined(UNIX_CYGWIN32)
                    if ((errno == EINVAL) || (errno == EACCES))
                    #else
                    if (errno == EINVAL)
                    #endif
                      # kein symbolisches Link
                      to_ptr[-1] = '/'; # wieder den '/' eintragen
                    else
                      return NULL; # Fehler
                  }
                }
              }
              #endif
              break;
          }
        }
      } # dann zum nächsten subdir
      # ein '/' am Ende streichen:
      if ((to_ptr[-1] == '/')
          #ifdef PATHNAME_UNIX_UNC
          && (to_ptr > resolved_path+2)
          #else
          && (to_ptr > resolved_path+1)
          #endif
         )
        to_ptr--;
      to_ptr[0] = 0; # durch 0 abschließen
      return resolved_path; # fertig
    }
#endif
#ifdef RISCOS
  # SYNOPSIS
  #   char* realpath (char* path, char resolved_path[MAXPATHLEN]);
  # RETURN VALUES
  #   realpath() returns a pointer to the resolved_path on success.
  #   On failure, it returns NULL and sets errno to indicate the error.
  local char* realpath (char* path, char* resolved_path);
  #include <sys/os.h>
  local char* realpath(path,resolved_path)
    var char* path;
    var char* resolved_path;
    {
      var int handle;
      var int r[10];
      #if 0 # Both of these implementations should work.
      if (os_fopen(0x40,path,&handle))
        return NULL;
      r[0] = 7; r[1] = handle; r[2] = (long)resolved_path; r[5] = MAXPATHLEN;
      os_swi(9,r);
      os_fclose(handle);
      #else
      var os_error* err;
      r[0] = 37; r[1] = (long)path; r[2] = (long)resolved_path;
      r[3] = 0; r[4] = 0; r[5] = MAXPATHLEN;
      err = os_swi(0x29,r);
      if (err) {
        __seterr(err); return NULL;
      }
      #endif
      if (r[5] <= 0) {
        errno = ENOMEM /* ENAMETOOLONG would be better, but does not yet exist */;
        return NULL;
      }
      return resolved_path;
    }
#endif

# Creates a new subdirectory.
# make_directory(pathstring);
# > pathstring: result of shorter_directory(...)
# > STACK_0: pathname
  local inline void make_directory (char* pathstring);
  local inline void make_directory(pathstring)
    var char* pathstring;
    {
      #ifdef AMIGAOS
      set_break_sem_4();
      begin_system_call();
      {
        var BPTR lock = CreateDir(pathstring); # Unterdirectory erzeugen
        if (lock==BPTR_NULL) {
          end_system_call(); OS_file_error(STACK_0);
        }
        UnLock(lock); # Lock freigeben
      }
      end_system_call();
      clr_break_sem_4();
      #endif
      #if defined(UNIX) || defined(EMUNIX) || defined(RISCOS)
      begin_system_call();
      if (mkdir(pathstring,0777)) { # Unterdirectory erzeugen
        end_system_call(); OS_file_error(STACK_0);
      }
      end_system_call();
      #endif
      #ifdef WIN32_NATIVE
      begin_system_call();
      if (! CreateDirectory(pathstring,NULL) ) { # Unterdirectory erzeugen
        end_system_call(); OS_file_error(STACK_0);
      }
      end_system_call();
      #endif
    }

# Deletes a subdirectory.
# delete_directory(pathstring);
# > pathstring: result of shorter_directory(...)
# > STACK_0: pathname
  local inline void delete_directory (char* pathstring);
  local inline void delete_directory(pathstring)
    var char* pathstring;
    {
      #ifdef AMIGAOS
      # Noch Test, ob's auch ein Directory und kein File ist??
      begin_system_call();
      if (! DeleteFile(pathstring) ) { # Unterdirectory löschen
        end_system_call(); OS_file_error(STACK_0);
      }
      end_system_call();
      #endif
      #if defined(UNIX) || defined(EMUNIX)
      begin_system_call();
      if (rmdir(pathstring)) { # Unterdirectory löschen
        end_system_call(); OS_file_error(STACK_0);
      }
      end_system_call();
      #endif
      #ifdef RISCOS
      begin_system_call();
      if (unlink(pathstring)) { # Unterdirectory löschen
        end_system_call(); OS_file_error(STACK_0);
      }
      end_system_call();
      #endif
      #ifdef WIN32_NATIVE
      begin_system_call();
      if (! RemoveDirectory(pathstring) ) { # Unterdirectory löschen
        end_system_call(); OS_file_error(STACK_0);
      }
      end_system_call();
      #endif
    }

#if defined(MSDOS) || defined(WIN32_NATIVE)
# Changes the operating system's current directory.
# change_directory(pathstring);
# > pathstring: directory, ASCIZ-String
# > STACK_0: pathname
  local inline void change_current_directory (char* pathstring);
  local inline void change_current_directory(pathstring)
    var char* pathstring;
    {
      begin_system_call();
      #ifdef MSDOS
        if (!( chdir(pathstring) ==0)) {
          end_system_call(); OS_file_error(STACK_0);
        }
      #endif
      #ifdef WIN32_NATIVE
        if (!SetCurrentDirectory(pathstring)) {
          end_system_call(); OS_file_error(STACK_0);
        }
      #endif
      end_system_call();
    }
#endif

# Delete a file.
# delete_existing_file(pathstring);
# It is known that the file exists.
# > pathstring: file name, ASCIZ-String
# > STACK_0: pathname
  local inline void delete_existing_file (char* pathstring);
  local inline void delete_existing_file(pathstring)
    var char* pathstring;
    {
      #if defined(UNIX) || defined(EMUNIX) || defined(RISCOS)
        begin_system_call();
        if (!( unlink(pathstring) ==0)) {
          end_system_call(); OS_file_error(STACK_0);
        }
        end_system_call();
      #endif
      #if defined(AMIGAOS) || defined(WIN32_NATIVE)
        begin_system_call();
        if (! DeleteFile(pathstring) ) {
          end_system_call(); OS_file_error(STACK_0);
        }
        end_system_call();
      #endif
    }

# Delete a file.
# delete_file_if_exists(pathstring);
# No error is signalled if the file does not exist.
# > pathstring: file name, ASCIZ-String
# > STACK_0: pathname
# < result: whether the file existed
  local inline bool delete_file_if_exists (char* pathstring);
  local inline bool delete_file_if_exists(pathstring)
    var char* pathstring;
    {
      var bool exists = true;
      #if defined(UNIX) || defined(EMUNIX) || defined(RISCOS)
        begin_system_call();
        if (!( unlink(pathstring) ==0)) {
          if (!(errno==ENOENT)) { # nicht gefunden -> OK
            end_system_call(); OS_file_error(STACK_0); # sonstigen Error melden
          }
          exists = false;
        }
        end_system_call();
      #endif
      #ifdef AMIGAOS
        begin_system_call();
        if (! DeleteFile(pathstring) ) {
          if (!(IoErr()==ERROR_OBJECT_NOT_FOUND)) { # nicht gefunden -> OK
            end_system_call(); OS_file_error(STACK_0); # sonstigen Error melden
          }
          exists = false;
        }
        end_system_call();
      #endif
      #ifdef WIN32_NATIVE
        begin_system_call();
        if (! DeleteFile(pathstring) ) {
          if (!(GetLastError()==ERROR_FILE_NOT_FOUND || GetLastError()==ERROR_PATH_NOT_FOUND || GetLastError()==ERROR_BAD_NETPATH)) {
            end_system_call(); OS_file_error(STACK_0);
          }
          exists = false;
        }
        end_system_call();
      #endif
      return exists;
    }

# Delete a file being the target of a subsequent rename.
# delete_file_before_rename(pathstring);
# No error is signalled if the file does not exist.
# > pathstring: file name, ASCIZ-String
# > STACK_0: pathname
  local inline void delete_file_before_rename (char* pathstring);
  local inline void delete_file_before_rename(pathstring)
    var char* pathstring;
    {
      #if !defined(UNIX) # rename() on Unix does it automatically
        delete_file_if_exists(pathstring);
      #endif
    }

# Rename a file.
# rename_existing_file(old_pathstring,new_pathstring);
# It is known that the old_pathstring exists.
# On platforms except UNIX, it is known that new_pathstring does not exist.
# > old_pathstring: old file name, ASCIZ-String
# > new_pathstring: new file name, ASCIZ-String
# > STACK_0: pathname
  local inline void rename_existing_file (char* old_pathstring, char* new_pathstring);
  local inline void rename_existing_file(old_pathstring,new_pathstring)
    var char* old_pathstring;
    var char* new_pathstring;
    {
      #if defined(UNIX) || defined(EMUNIX) || defined(RISCOS)
        begin_system_call();
        if ( rename(old_pathstring,new_pathstring) <0) { # Datei umbenennen
          end_system_call(); OS_file_error(STACK_0); # Error melden
        }
        end_system_call();
      #endif
      #ifdef AMIGAOS
        begin_system_call();
        if (! Rename(old_pathstring,new_pathstring) ) {
          end_system_call(); OS_file_error(STACK_0);
        }
        end_system_call();
      #endif
      #ifdef WIN32_NATIVE
        begin_system_call();
        if (! MoveFile(old_pathstring,new_pathstring) ) {
          end_system_call(); OS_file_error(STACK_0);
        }
        end_system_call();
      #endif
    }

# Rename a file.
# rename_file_to_nonexisting(old_pathstring,new_pathstring);
# It is known that new_pathstring does not exist.
# > old_pathstring: old file name, ASCIZ-String
# > new_pathstring: new file name, ASCIZ-String
# > STACK_3: old pathname
# > STACK_1: new pathname
  local inline void rename_file_to_nonexisting (char* old_pathstring, char* new_pathstring);
  local inline void rename_file_to_nonexisting(old_pathstring,new_pathstring)
    var char* old_pathstring;
    var char* new_pathstring;
    {
      #if defined(UNIX) || defined(EMUNIX) || defined(RISCOS)
        begin_system_call();
        if ( rename(old_pathstring,new_pathstring) <0) { # Datei umbenennen
          if (errno==ENOENT) {
            end_system_call(); OS_file_error(STACK_3);
          } else {
            end_system_call(); OS_file_error(STACK_1);
          }
        }
        end_system_call();
      #endif
      #ifdef AMIGAOS
        begin_system_call();
        if (! Rename(old_pathstring,new_pathstring) ) {
          if (IoErr()==ERROR_OBJECT_NOT_FOUND) {
            end_system_call(); OS_file_error(STACK_3);
          } else {
            end_system_call(); OS_file_error(STACK_1);
          }
        }
        end_system_call();
      #endif
      #ifdef WIN32_NATIVE
        begin_system_call();
        if (! MoveFile(old_pathstring,new_pathstring) ) {
          if (GetLastError()==ERROR_FILE_NOT_FOUND || GetLastError()==ERROR_PATH_NOT_FOUND || GetLastError()==ERROR_BAD_NETPATH) {
            end_system_call(); OS_file_error(STACK_3);
          } else {
            end_system_call(); OS_file_error(STACK_1);
          }
        }
        end_system_call();
      #endif
    }


# =============================================================================
#                         P A T H N A M E S

# All simple-strings occurring in pathnames are in fact normal-simple-strings.

#ifdef PATHNAME_AMIGAOS
# Komponenten:
# HOST          stets NIL
# DEVICE        NIL oder Simple-String
# DIRECTORY     (Startpoint . Subdirs) wobei
#                Startpoint = :RELATIVE | :ABSOLUTE
#                Subdirs = () | (subdir . Subdirs)
#                subdir = :WILD-INFERIORS (bedeutet "**" oder "...", alle Subdirectories) oder
#                subdir = :PARENT (bedeutet "/" statt "subdir/") oder
#                subdir = Simple-String, evtl. mit Wildcard-Zeichen ? und *
# NAME          NIL oder
#               Simple-String, evtl. mit Wildcard-Zeichen ? und *
#               (auch :WILD bei der Eingabe)
# TYPE          NIL oder
#               Simple-String, evtl. mit Wildcard-Zeichen ? und *
#               (auch :WILD bei der Eingabe)
# VERSION       stets NIL (auch :WILD oder :NEWEST bei Eingabe)
# Constraint: Startpoint = :RELATIVE nur, falls Device = NIL;
#             bei angegebenem Device gibt es also nur absolute Pathnames!
# Ein AMIGAOS-Filename wird folgendermaßen in Name und Typ aufgespalten:
#   falls kein '.' im Filename: Name = alles, Typ = NIL,
#   falls '.' im Filename: Name = alles vor, Typ = alles nach dem letzten '.' .
# Groß-/Klein-Schreibung innerhalb der Strings wird bei Vergleichen ignoriert,
# aber ansonsten findet keine Groß/Klein-Umwandlung statt.
# Wenn ein Pathname vollständig spezifiziert sein muss (keine Wildcards),
# ist :WILD, :WILD-INFERIORS nicht erlaubt, keine Wildcard-Zeichen in den
# Strings, bei NAME evtl. auch nicht NIL.
# Externe Notation:  device:sub1.typ/sub2.typ/name.typ
# mit Defaults:             sub1.typ/sub2.typ/name.typ
# oder                                        name.typ
# oder                      sub1.typ/ ** /sub3.typ/x*.lisp  (ohne Spaces!)
# oder Ähnliches.
# Formal:
#   ch ::= beliebgiges Character außer ':','/' und '*','?'
#   name ::= {ch}+
#   device ::= [ <leer> | ':' | name ':' ]
#              ; leer = aktuelles Device, relativ ab aktuellem Directory
#              ; ':'  = aktuelles Device, absolut (ab root bei Disks)
#              ; name ':' = angegebenes Device, absolut (ab root bei Disks)
#   subdir ::= [ <leer> | name ]                ; leer = '..'
#   pathname ::= device { subdir '/' }* name
# Beispiele:
#   String        Device    Directory                unser Pathname
#   ------        ------    ---------                --------------
#   'c:foo'       'C',     device->foo               "c" (:ABSOLUTE "foo")
#   'c:foo/'      'C',     device->foo               "c" (:ABSOLUTE "foo")
#   'c:foo/bar'   'C',     device->foo->bar          "c" (:ABSOLUTE "foo" "bar")
#   'c:/foo'      'C',     device->up->foo           "c" (:ABSOLUTE :PARENT "foo")
#   'c:'          'C',     device                    "c" (:ABSOLUTE)
#   ':foo'        current, device->root->foo         NIL (:ABSOLUTE "foo")
#   'foo'         current, device->foo               NIL (:RELATIVE "foo")
#   '/foo'        current, device->up->foo           NIL (:RELATIVE :PARENT "foo")
#   '//foo/bar'   current, device->up->up->foo->bar  NIL (:RELATIVE :PARENT :PARENT "foo" "bar")
#   ''            current, device                    NIL (:RELATIVE)
# An einen Pathstring, der nichtleer ist und der nicht mit ':' oder '/'
# endet, kann ein '/' angehängt werden, ohne seine Semantik zu verändern.
# Dieser '/' muss angehängt werden, bevor man eine weitere nichtleere
# Komponente anhängen kann.
# An einen Pathstring, der leer ist oder mit ':' oder '/' endet, ein '/'
# anzuhängen, bedeutet aber, zum Parent Directory aufzusteigen!
# Bei uns wird jeder Pathstring, der leer ist oder mit ':' oder '/' endet,
# als Directory-Pathname (mit Name=NIL und Type=NIL) interpretiert.
#endif

#ifdef PATHNAME_UNIX
# Komponenten:
# HOST          stets NIL
# DEVICE        stets NIL
# DIRECTORY     (Startpoint . Subdirs) wobei
#                Startpoint = :RELATIVE | :ABSOLUTE
#                Subdirs = () | (subdir . Subdirs)
#                subdir = :WILD-INFERIORS (bedeutet "**" oder "...", alle Subdirectories) oder
#                subdir = Simple-String, evtl. mit Wildcard-Zeichen ? und *
# NAME          NIL oder
#               Simple-String, evtl. mit Wildcard-Zeichen ? und *
#               (auch :WILD bei der Eingabe)
# TYPE          NIL oder
#               Simple-String, evtl. mit Wildcard-Zeichen ? und *
#               (auch :WILD bei der Eingabe)
# VERSION       stets NIL (auch :WILD oder :NEWEST bei Eingabe)
# Ein UNIX-Filename wird folgendermaßen in Name und Typ aufgespalten:
#   falls kein '.' im Filename: Name = alles, Typ = NIL,
#   falls '.' im Filename: Name = alles vor, Typ = alles nach dem letzten '.' .
# Wenn ein Pathname vollständig spezifiziert sein muss (keine Wildcards),
# ist :WILD, :WILD-INFERIORS nicht erlaubt, keine Wildcard-Zeichen in den
# Strings, bei NAME evtl. auch nicht NIL.
# Externe Notation:  server:/sub1.typ/sub2.typ/name.typ
# mit Defaults:             /sub1.typ/sub2.typ/name.typ
# oder                                         name.typ
# oder                      /sub1.typ/ ** /sub3.typ/x*.lisp  (ohne Spaces!)
# oder Ähnliches.
# If NAME starts with a dot, (parse-namestring (namestring pathname)) will not
# be the same as pathname.
#endif

#ifdef PATHNAME_OS2
# Komponenten:
# HOST          stets NIL
# DEVICE        NIL oder :WILD oder "A"|...|"Z"
# DIRECTORY     (Startpoint . Subdirs) wobei
#                Startpoint = :RELATIVE | :ABSOLUTE
#                Subdirs = () | (subdir . Subdirs)
#                subdir = :WILD-INFERIORS (bedeutet "**" oder "...", alle Subdirectories) oder
#                subdir = Simple-String, evtl. mit Wildcard-Zeichen ? und *
# NAME          NIL oder
#               Simple-String, evtl. mit Wildcard-Zeichen ? und *
#               (auch :WILD bei der Eingabe)
# TYPE          NIL oder
#               Simple-String, evtl. mit Wildcard-Zeichen ? und *
#               (auch :WILD bei der Eingabe)
# VERSION       stets NIL (auch :WILD oder :NEWEST bei Eingabe)
# Ein OS/2-Filename wird folgendermaßen in Name und Typ aufgespalten:
#   falls kein '.' im Filename: Name = alles, Typ = NIL,
#   falls '.' im Filename: Name = alles vor, Typ = alles nach dem letzten '.' .
# Wenn ein Pathname vollständig spezifiziert sein muss (keine Wildcards),
# ist :WILD, :WILD-INFERIORS nicht erlaubt, keine Wildcard-Zeichen in den
# Strings, bei NAME evtl. auch nicht NIL.
# Externe Notation:       A:\sub1.typ\sub2.typ\name.typ
# mit Defaults:             \sub1.typ\sub2.typ\name.typ
# oder                                         name.typ
# oder                    *:\sub1.typ\**\sub3.typ\x*.lisp
# oder Ähnliches.
# Statt '\' ist - wie unter DOS üblich - auch '/' erlaubt.
#endif

#ifdef PATHNAME_WIN32
# Komponenten:
# HOST          NIL oder Simple-String (Wildcard-Zeichen sind ohne Bedeutung)
# DEVICE        NIL oder :WILD oder "A"|...|"Z"
# DIRECTORY     (Startpoint . Subdirs) wobei
#                Startpoint = :RELATIVE | :ABSOLUTE
#                Subdirs = () | (subdir . Subdirs)
#                subdir = :WILD-INFERIORS (bedeutet "**" oder "...", alle Subdirectories) oder
#                subdir = Simple-String, evtl. mit Wildcard-Zeichen ? und *
# NAME          NIL oder
#               Simple-String, evtl. mit Wildcard-Zeichen ? und *
#               (auch :WILD bei der Eingabe)
# TYPE          NIL oder
#               Simple-String, evtl. mit Wildcard-Zeichen ? und *
#               (auch :WILD bei der Eingabe)
# VERSION       stets NIL (auch :WILD oder :NEWEST bei Eingabe)
# If HOST is non-NIL, DEVICE must be NIL.
# Ein WIN32-Filename wird folgendermaßen in Name und Typ aufgespalten:
#   falls kein '.' im Filename: Name = alles, Typ = NIL,
#   falls '.' im Filename: Name = alles vor, Typ = alles nach dem letzten '.' .
# Wenn ein Pathname vollständig spezifiziert sein muss (keine Wildcards),
# ist :WILD, :WILD-INFERIORS nicht erlaubt, keine Wildcard-Zeichen in den
# Strings, bei NAME evtl. auch nicht NIL.
# Externe Notation:       A:\sub1.typ\sub2.typ\name.typ
# mit Defaults:             \sub1.typ\sub2.typ\name.typ
# oder                                         name.typ
# oder                    *:\sub1.typ\**\sub3.typ\x*.lisp
# oder Ähnliches.
# Statt '\' ist - wie unter DOS üblich - auch '/' erlaubt.
# If HOST is non-NIL and the DIRECTORY's Startpoint is not :ABSOLUTE,
# (parse-namestring (namestring pathname)) will not be the same as pathname.
#endif

#ifdef PATHNAME_RISCOS
#
# Peter Burwood <clisp@arcangel.demon.co.uk> writes:
#
# RISC OS provides several filing systems as standard (ADFS, IDEFS, NetFS,
# RamFS, NetPrint) and support for extra filing systems (DOSFS, ResourceFS and
# DeviceFS).
#
# A module called FileSwitch is at the centre of all filing system operation
# in RISC OS. FileSwitch provides a common core of functions used by all
# filing systems. It only provides the parts of these services that are device
# independent. The device dependant services that control the hardware are
# provided by separate modules, which are the actual filing systems.
# FileSwitch keeps track of active filing systems and switches betwen them as
# necessary.
#
# One of the filing system modules that RISC OS provides is FileCore. It takes
# the normal calls that FileSwitch sends to a filing system module, and
# converts them to a simpler set of calls to modules that control the
# hardware. Unlike FileSwitch it creates a fresh instantiation of itself for
# each module that it supports. Using FileCore to build filing system modules
# imposes a more rigid structure on it, as more of the filing system is
# predefined.
#
# As well as standard filing systems, FileSwitch supports image filing
# systems. These provide facilities for RISC OS to handle media in foreign
# formats, and to support `image files' (or partitions) in those formats.
# Rather than accessing the hardware directly they rely on standard RISC OS
# filing systems to do so. DOSFS is an example of an image filing system used
# to handle DOS format discs.
#
# Terminology
#
# A pathname may include a filing system name, a special field, a media name
# (e.g., a disc name), directory name(s), and the name of the object itself;
# each of these parts of a pathname is known as an `element' of the pathname.
#
# Filenames
#
# Filename `elements' may be up to ten characters in length on FileCore-based
# filing systems and on NetFS. These characters may be digits or letters.
# FileSwitch makes no distinction between upper and lower case, although
# filing systems can do so. As a general rule, you should not use top-bit-set
# characters in filenames, although some filing systems (such as
# FileCore-based ones) support them. Other characters may be used provided
# they do not have a special significance. Those that do are listed below :
#
#    .   Separates directory specifications, e.g., $.fred
#    :   Introduces a drive or disc specification, e.g., :0, :bigdisc. It also
#        marks the end of a filing system name, e.g., adfs:
#    *   Acts as a `wildcard' to match zero or more characters.
#    #   Acts as a `wildcard' to match any single character.
#    $   is the name of the root directory of the disc.
#    &   is the user root directory (URD)
#    @   is the currently selected directory (CSD)
#    ^   is the `parent' directory
#    %   is the currently selected library (CSL)
#    \   is the previously selected directory (PSD)
#
# Directories
#
# The root directory, $, forms the top of the directory hierarchy
# of the media which contains the CSD. $ does not have a parent directory,
# trying to access its parent will just access $. Each directory name is
# separated by a '.' character. For example:
#
#    $.Documents.Memos
#    %.cc
#
# Filing Systems
#
# Files may also be accessed on filing systems other than the current one by
# prefixing the filename with a filing system specification. A filing system
# name may appear between '-' characters, or suffixed by a ':', though the
# latter is advised since '-' can also be used to introduce a parameter on a
# command line, or as part of a file name. For example:
#
#    -net-$.SystemMesg
#    adfs:%.aasm
#
# Special Fields
#
# Special fields are used to supply more information to the filing system than
# you can using standard path names; for example NetFS and NetPrint use them
# to specify server addresses or names. They are introduced by a '#'
# character; a variety of syntaxes are possible:
#
#    net#MJHardy::disc1.mike
#       #MJHardy::disc1.mike
#   -net#MJHardy-:disc1.mike
#      -#MJHardy-:disc1.mike
#
# The special fields here are all MJHardy, and give the name of the fileserver
# to use. Special fields may use any character except for control characters,
# double quote '"', solidus '|' and space. If a special field contains a hypen
# you may only use the first two syntaxes given above.
#
# File$Path and Run$Path
#
# These two special variables control exactly where a file will be looked for,
# according to the operation being performed on it.
#
#    File$Path   for read operations
#    Run$Path    for execute operations
#
# The contents of each variable should expand to a list or prefixes, separated
# by commas. When a read operation is performed then the prefixes in File$Path
# are used in the order in which they are listed. The first object that
# matches is used, whether it be a file or directory. Similarly any execute
# operation uses the prefixes in Run$Path. These search paths are only used
# when the pathname does not contain an explicit filing system reference,
# e.g., executing adfs:file will not use Run$Path.
#
# Other path variables
#
# You can set up other path variables and use them as pseudo filing systems.
# For example if you typed:
#
#    *Set Source$Path adfs:$.src.,adfs:$.public.src.
#
# you could then refer to the pseudo filing system as Source: or (less
# preferable) as -Source-. These path variables work in the same was as
# File$Path and Run$Path.
#
# NOTE: Path variables are not implemented in this version of CLISP. A
# workaround for this is to use "<Foo$Path>" instead of "Foo:" until they are
# made available.
#
#
# from Lisp-string notation to internal representation
# ----------------------------------------------------
# NO swapping. "foo.lisp" means file type "lisp" and file name "foo".
# This is pseudo-BNF:
#
# legal character ::= any ISO latin-1 graphic character >= ' ' except
#                     '.' ':' '*' '#' '$' '&' '@' '^' '%' '\' '?'
#
# extended legal character ::= any ISO latin-1 graphic character >= ' ' except
#                              ':' '"' '|'
#
# legal-wild char ::= legal char | '*' | '#' | '?'
#
# host ::=   '-' { extended legal char except '-' }+ '-'
#          | { extended legal char except '-' } { extended legal char }* ':'
#          | empty
#
# device ::=   ':' { legal char }+ '.'
#            | empty
#
# directory ::=   { '$' | '&' | '@' | '%' | '\' } '.' { subdirectory }*
#               | { subdirectory }+
#               | empty
#
# '$' -> :ABSOLUTE :ROOT, '&' -> :ABSOLUTE :HOME, '@' -> :ABSOLUTE :CURRENT,
# '%' -> :ABSOLUTE :LIBRARY, '\' -> :ABSOLUTE :PREVIOUS, else :RELATIVE.
#
# subdirectory ::= { '^' | { legal-wild char }+ } '.'
#                  '^' -> :PARENT
#
# filename ::= { { legal-wild char }+ | empty }
#
# filetype ::= { '.' { legal-wild char }+ | empty }
#
# pathname ::= host device directory filename filetype
#
# Examples:
# String                          Hostname Device  Directory            Name         Type
# -net-$.SystemMesg                "net"   NIL     (:ABSOLUTE :ROOT)    "SystemMesg" NIL
# net#MJHardy::disc1.mike    "net#MJHardy" "disc1" (:ABSOLUTE :ROOT)    "mike"       NIL
# #MJHardy::disc1.mike          "#MJHardy" "disc1" (:ABSOLUTE :ROOT)    "mike"       NIL
# -net#MJHardy-:disc1.mike   "net#MJHardy" "disc1" (:ABSOLUTE :ROOT)    "mike"       NIL
# -#MJHardy-:disc1.mike         "#MJHardy" "disc1" (:ABSOLUTE :ROOT)    "mike"       NIL
# @.foo                            NIL     NIL     (:ABSOLUTE :CURRENT) "foo"        NIL
# foo                              NIL     NIL     (:RELATIVE)          "foo"        NIL
# ^.                               NIL     NIL     (:RELATIVE :PARENT)  NIL          NIL
# @.^.                             NIL     NIL     (:ABSOLUTE :CURRENT :PARENT) NIL  NIL
# foo.bar                          NIL     NIL     (:RELATIVE)          "foo"        "bar"
# foo.bar.baz                      NIL     NIL     (:RELATIVE "foo")    "bar"        "baz"
# foo.bar.                         NIL     NIL     (:RELATIVE "foo" "bar") NIL       NIL
# foo.@.                       illegal
#
# from internal representation to RISCOS string
# ---------------------------------------------
#
# with swapping _only_ of name/type components.
#
# Hostname    Device  Directory                   Name    Type      RISCOS String
#
# "net"       "disc1" (:ABSOLUTE :ROOT)           "foo"   NIL       "net::disc1.$.foo"
# "net#MJ"    "disc1" (:ABSOLUTE :ROOT "foo")     "bar"   "baz"     "net#MJ::disc1.$.foo.baz.bar"
# "adfs"      "4"     (:ABSOLUTE :ROOT "foo" "bar") NIL   NIL       "adfs::4.$.foo.bar"
# NIL         "disc1" (:ABSOLUTE :ROOT "foo")     "bar"   NIL       ":disc1.$.foo.bar"
# NIL         "disc1" (:ABSOLUTE :CURRENT)        NIL     NIL       illegal here
# NIL         "disc1" (:RELATIVE)                 NIL     NIL       ":disc1."
# NIL         "disc1" NIL                         NIL     NIL       ":disc1."
# NIL         NIL     (:ABSOLUTE :ROOT)           "foo"   NIL       "$.foo"
# NIL         NIL     (:ABSOLUTE :CURRENT)        "foo"   NIL       "@.foo"
# NIL         NIL     (:RELATIVE)                 "foo"   "bar"     "bar.foo"
# NIL         NIL     (:RELATIVE "foo")           "bar"   "baz"     "foo.baz.bar"
# NIL         NIL     (:ABSOLUTE :LIBRARY)        "bar"   NIL       "%.bar"
# NIL         NIL     (:ABSOLUTE :LIBRARY "foo")  "bar"   NIL       "%.foo.bar"
# NIL         NIL     (:RELATIVE)                 "foo"   "bar"     "bar.foo"
# NIL         NIL     (:RELATIVE "foo")           "bar"   NIL       "foo.bar"
# NIL         NIL     (:RELATIVE "foo")           NIL     "bar"     illegal here
#
# That is, the RISCOS string is the flattenation-concatenation of
#   (append
#     (if (null hostname) "" (append hostname ":"))
#     (if (null device) "" (append ":" device "."))
#     (case (pop directory)
#       (:ABSOLUTE (case (pop directory)
#                          (:ROOT "$.")
#                          (:HOME "&.")
#                          (:CURRENT "@.")
#                          (:LIBRARY "%.")
#                          (:PREVIOUS "\\.")
#       )          )
#       (:RELATIVE "")
#     )
#     (mapcar (lambda (subdir) (append subdir ".")) directory)
#     (if (null name)
#       (if (null type) "" (error "type with name illegal here"))
#       (if (null type)
#         name
#         (append type "." name)
#   ) ) )
#
# internal representation
# -----------------------
#
# Pathname components:
# HOST          Simple-String or NIL
# DEVICE        Simple-String or NIL
# DIRECTORY     (Startpoint . Subdirs) where
#                Startpoint = :RELATIVE | :ABSOLUTE anchor
#                anchor = :ROOT | :HOME | :CURRENT | :LIBRARY | :PREVIOUS
#                Subdirs = () | (subdir . Subdirs)
#                subdir = :PARENT or
#                subdir = simple string, may contain wildcard characters ?,# and *
# NAME          NIL or
#               simple string, may contain wildcard characters ?,# and *
#               (may also be specified as :WILD)
# TYPE          NIL or
#               simple string, may contain wildcard characters ?,# and *
#               (may also be specified as :WILD)
# VERSION       always NIL (may also be specified as :WILD or :NEWEST)
#
# Constraint: startpoint /= :ABSOLUTE :ROOT only if device = NIL. If the device
# is specified, the pathname must be :ABSOLUTE :ROOT.
#
# Komponenten:
# HOST          Simple-String oder NIL
# DEVICE        Simple-String oder NIL
# DIRECTORY     (Startpoint . Subdirs) wobei
#                Startpoint = :RELATIVE | :ABSOLUTE Anker
#                Anker = :ROOT | :HOME | :CURRENT | :LIBRARY | :PREVIOUS
#                Subdirs = () | (subdir . Subdirs)
#                subdir = :PARENT oder
#                subdir = Simple-String, evtl. mit Wildcard-Zeichen ?,# und *
# NAME          NIL oder
#               Simple-String, evtl. mit Wildcard-Zeichen ?,# und *
#               (auch :WILD bei der Eingabe)
# TYPE          NIL oder
#               Simple-String, evtl. mit Wildcard-Zeichen ?,# und *
#               (auch :WILD bei der Eingabe)
# VERSION       stets NIL (auch :WILD oder :NEWEST bei Eingabe)
#
#endif

#ifdef LOGICAL_PATHNAMES
# Komponenten von Logical Pathnames:
# HOST          Simple-String oder NIL
# DEVICE        stets NIL
# DIRECTORY     (Startpoint . Subdirs) wobei
#                Startpoint = :RELATIVE | :ABSOLUTE
#                Subdirs = () | (subdir . Subdirs)
#               subdir = :WILD-INFERIORS (bedeutet "**", alle Subdirectories) oder
#               subdir = :WILD (bedeutet "*") oder
#               subdir = Simple-String, evtl. mit Wildcard-Zeichen *
# NAME          NIL oder
#               :WILD (bedeutet "*") oder
#               Simple-String, evtl. mit Wildcard-Zeichen *
# TYPE          NIL oder
#               :WILD (bedeutet "*") oder
#               Simple-String, evtl. mit Wildcard-Zeichen *
# VERSION       NIL oder :NEWEST oder :WILD oder Integer
# Externe Notation: siehe CLtl2 S. 628-629.
#endif

# Wandelt Strings in Normal-Simple-Strings um.
# subst_coerce_normal_ss(obj)
# can trigger GC
  local object subst_coerce_normal_ss (object obj);
  local object subst_coerce_normal_ss(obj)
    var object obj;
    {
      if (atomp(obj)) {
        if (stringp(obj))
          return coerce_normal_ss(obj);
        else
          return obj;
      }
      check_STACK(); check_SP();
      pushSTACK(obj);
      # rekursiv für den CAR aufrufen:
      {
        var object new_car = subst_coerce_normal_ss(Car(obj));
        pushSTACK(new_car);
      }
      # rekursiv für den CDR aufrufen:
      {
        var object new_cdr = subst_coerce_normal_ss(Cdr(STACK_1));
        if (eq(new_cdr,Cdr(STACK_1)) && eq(STACK_0,Car(STACK_1))) {
          obj = STACK_1; skipSTACK(2); return obj;
        } else {
          # (CONS new_car new_cdr)
          STACK_1 = new_cdr;
          var object new_cons = allocate_cons();
          Car(new_cons) = popSTACK(); Cdr(new_cons) = popSTACK();
          return new_cons;
        }
      }
    }

# Wandelt Groß-/Klein-Schreibung zwischen :LOCAL und :COMMON um.
# common_case(string)
# > string: Normal-Simple-String oder Symbol/Zahl
# < ergebnis: umgewandelter Normal-Simple-String oder dasselbe Symbol/Zahl
# can trigger GC
  local object common_case (object string);
# Dasselbe, rekursiv wie mit SUBST:
  local object subst_common_case (object obj);
  # Betriebssystem mit Vorzug für Kleinbuchstaben oder Capitalize
  local object common_case(string)
    var object string;
    {
      if (!simple_string_p(string))
        return string;
      var uintL len = Sstring_length(string);
      # Suche, ob Groß- oder Kleinbuchstaben (oder beides) vorkommen:
      var bool all_upper = true;
      var bool all_lower = true;
      if (len > 0) {
        var const chart* ptr = &TheSstring(string)->data[0];
        var uintL count;
        dotimespL(count,len, {
          var chart ch = *ptr++;
          if (!chareq(ch,up_case(ch)))
            all_upper = false;
          if (!chareq(ch,down_case(ch)))
            all_lower = false;
          if (!all_upper && !all_lower)
            break;
        });
      }
      if (all_upper == all_lower)
        # all_upper = all_lower = true: Nichts zu konvertieren.
        # all_upper = all_lower = false: "Mixed case represents itself."
        return string;
      if (all_upper)
        # all_upper = true, all_lower = false: STRING-DOWNCASE
        return string_downcase(string);
      else
        # all_upper = false, all_lower = true: STRING-UPCASE
        return string_upcase(string);
    }
  local object subst_common_case(obj)
    var object obj;
    {
      if (atomp(obj))
        return common_case(obj);
      check_STACK(); check_SP();
      pushSTACK(obj);
      # rekursiv für den CAR aufrufen:
      {
        var object new_car = subst_common_case(Car(obj));
        pushSTACK(new_car);
      }
      # rekursiv für den CDR aufrufen:
      {
        var object new_cdr = subst_common_case(Cdr(STACK_1));
        if (eq(new_cdr,Cdr(STACK_1)) && eq(STACK_0,Car(STACK_1))) {
          obj = STACK_1; skipSTACK(2); return obj;
        } else {
          # (CONS new_car new_cdr)
          STACK_1 = new_cdr;
          var object new_cons = allocate_cons();
          Car(new_cons) = popSTACK(); Cdr(new_cons) = popSTACK();
          return new_cons;
        }
      }
    }

#ifdef LOGICAL_PATHNAMES

local bool legal_logical_word_char (chart ch);
local bool legal_logical_word_char(ch)
  var chart ch;
  {
    ch = up_case(ch);
    var cint c = as_cint(ch);
    if (((c >= 'A') && (c <= 'Z'))
        || ((c >= '0') && (c <= '9'))
        || (c == '-')
       )
      return true;
    else
      return false;
  }

#endif

#if HAS_HOST

# UP: Stellt fest, ob ein Character als Zeichen im Host-Teil eines Namestring
# erlaubt ist.
# legal_hostchar(ch)
# > chart ch: Character-Code
# < ergebnis: true falls erlaubt, false sonst
  local bool legal_hostchar (chart ch);
# NB: legal_logical_word_char(ch) impliziert legal_hostchar(ch).
  local bool legal_hostchar(ch)
    var chart ch;
    {
      #if defined(PATHNAME_RISCOS)
      return (graphic_char_p(ch)
              && !chareq(ch,ascii(':'))
              && !chareq(ch,ascii('"'))
              && !chareq(ch,ascii('|')));
      #elif defined(PATHNAME_WIN32)
      # This is just a guess. I don't know which characters are allowed in
      # Windows host names.
      var cint c = as_cint(ch);
      if ((c >= ' ') && (c <= '~')
          && (c != '"') && (c != '/') && (c != ':') && (c != '<') && (c != '>')
          && (c != '\\'))
        return true;
      else
        return false;
      #else
      return alphanumericp(ch) || chareq(ch,ascii('-'));
      #endif
    }

# UP: Überprüft ein optionales Host-Argument.
# test_optional_host(host,convert)
# > host: Host-Argument
# > convert: Flag, ob Case-Konversion erwünscht ist
# > subr_self: Aufrufer (ein SUBR)
# < ergebnis: gültige Host-Komponente
# can trigger GC
  local object test_optional_host (object host, bool convert);
  local object test_optional_host(host,convert)
    var object host;
    var bool convert;
    {
      if (eq(host,unbound))
        return NIL; # nicht angegeben -> NIL
      if (nullp(host))
        goto OK; # NIL ist OK
      # Sonst muss host ein String sein, dessen Zeichen alphanumerisch sind:
      if (!stringp(host)) {
        pushSTACK(host); # Wert für Slot DATUM von TYPE-ERROR
        pushSTACK(O(type_host)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
        pushSTACK(host);
        pushSTACK(TheSubr(subr_self)->name);
        fehler(type_error,
               GETTEXT("~: host should be NIL or a string, not ~")
              );
      }
      host = coerce_normal_ss(host); # als Normal-Simple-String
      if (convert)
        host = common_case(host);
      {
        var uintL len = Sstring_length(host);
        if (len > 0) {
          var const chart* charptr = &TheSstring(host)->data[0];
          dotimespL(len,len, {
            var chart ch = *charptr++;
            if (!legal_hostchar(ch))
              goto badhost;
          });
        }
      }
     OK: return host;
     badhost:
      pushSTACK(host);
      pushSTACK(TheSubr(subr_self)->name);
      fehler(parse_error,
             GETTEXT("~: illegal hostname ~")
            );
    }

#else

#ifdef LOGICAL_PATHNAMES

# UP: Überprüft ein optionales Host-Argument.
# test_optional_host(host)
# > host: Host-Argument
# > subr_self: Aufrufer (ein SUBR)
# < ergebnis: gültige Host-Komponente
# can trigger GC
  local object test_optional_host (object host);
  local object test_optional_host(host)
    var object host;
    {
      if (eq(host,unbound))
        return NIL; # nicht angegeben -> NIL
      if (nullp(host))
        goto OK; # NIL ist OK
      # Sonst muss host ein String sein, dessen Zeichen alphanumerisch sind:
      if (!stringp(host)) {
        pushSTACK(host); # Wert für Slot DATUM von TYPE-ERROR
        pushSTACK(O(type_host)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
        pushSTACK(host);
        pushSTACK(TheSubr(subr_self)->name);
        fehler(type_error,
               GETTEXT("~: host should be NIL or a string, not ~")
              );
      }
      host = coerce_normal_ss(host); # als Normal-Simple-String
      {
        var uintL len = Sstring_length(host);
        if (len > 0) {
          var const chart* charptr = &TheSstring(host)->data[0];
          dotimespL(len,len, {
            var chart ch = *charptr++;
            if (!legal_logical_word_char(ch))
              goto badhost;
          });
        }
      }
     OK: return host;
     badhost:
      pushSTACK(host);
      pushSTACK(TheSubr(subr_self)->name);
      fehler(parse_error,
             GETTEXT("~: illegal hostname ~")
            );
    }

#else

# UP: Überprüft ein optionales Host-Argument.
# test_optional_host(host);
# > host: Host-Argument
# > subr_self: Aufrufer (ein SUBR)
# < ergebnis: gültige Host-Komponente
  local object test_optional_host (object host);
  local object test_optional_host(host)
    var object host;
    {
      if (!eq(host,unbound)) { # nicht angegeben -> OK
        if (!nullp(host)) { # angegeben -> sollte =NIL sein
          pushSTACK(host); # Wert für Slot DATUM von TYPE-ERROR
          pushSTACK(S(null)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
          pushSTACK(host);
          pushSTACK(TheSubr(subr_self)->name);
          fehler(type_error,
                 GETTEXT("~: host should be NIL, not ~")
                );
        }
      }
      return NIL;
    }

#endif

#endif

# Stellt fest, ob zwei Characters als Zeichen in Pathnames als gleich gelten.
# equal_pathchar(ch1,ch2)
# > chart ch1,ch2: Character-Codes
# < ergebnis: true falls gleich, false sonst
  #if !(defined(PATHNAME_AMIGAOS) || defined(PATHNAME_OS2) || defined(PATHNAME_WIN32))
    #define equal_pathchar(ch1,ch2)  chareq(ch1,ch2)
  #else # defined(PATHNAME_AMIGAOS) || defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
    # Case-insensitive, aber normalerweise ohne Konversion
    #define equal_pathchar(ch1,ch2)  chareq(up_case(ch1),up_case(ch2))
  #endif

# UP: Stellt fest, ob ein Character als Zeichen im Namens-/Typ-Teil eines
# Namestring erlaubt ist.
# legal_namechar(ch)
# > chart ch: Character-Code
# < ergebnis: true falls erlaubt, false sonst
  local bool legal_namechar (chart ch);
  local bool legal_namechar(ch)
    var chart ch;
    {
      var uintB c;
      #ifdef UNICODE
      # Check whether ch fits into a single byte in O(pathname_encoding).
      if (!(cslen(O(pathname_encoding),&ch,1) == 1)) return false;
      cstombs(O(pathname_encoding),&ch,1,&c,1); # causes error message if it doesn't fit
      #else
      c = as_cint(ch);
      #endif
      #ifdef VALID_FILENAME_CHAR # defined in unixconf.h
      #define ch c
      return VALID_FILENAME_CHAR || (ch=='*') || (ch=='?');
      #undef ch
      #else
      #ifdef PATHNAME_AMIGAOS
      return (graphic_char_p(ch) && !(c=='/') && !(c==':'));
      #endif
      #ifdef PATHNAME_UNIX
      return ((c>=' ') && (c<='~') && !(c=='/'));
      #endif
      #ifdef PATHNAME_OS2
      return (graphic_char_p(ch) && !(c=='\\') && !(c=='/') && !(c==':'));
      #endif
      #ifdef PATHNAME_WIN32
      return ((c >= 1) && (c <= 127) && (c != 34) /*&& (c != 42)*/ && (c != 47) && (c != 58) && (c != 60) && (c != 62) /*&& (c != 63)*/ && (c != 92)) || (c == 131) || ((c >= 160) && (c != 197) && (c != 206));
      #endif
      #ifdef PATHNAME_RISCOS
      return (graphic_char_p(ch) && !(c==':') && !(c=='.')
              && !(c=='$') && !(c=='&') && !(c=='@')
              && !(c=='^') && !(c=='%') && !(c=='\\')
              # Wild Characters '*' '#' '?' sind hier erlaubt.
             );
      #endif
      #endif
    }

# Stellt fest, ob ein Character ein Wildcard-Platzhalter für ein einzelnes
# Zeichen ist.
# singlewild_char_p(ch)
# > chart ch: Character-Code
# < ergebnis: true falls ja, false sonst
  #if !defined(PATHNAME_RISCOS)
    #define singlewild_char_p(ch)  chareq(ch,ascii('?'))
  #else # defined(PATHNAME_RISCOS)
    #define singlewild_char_p(ch)  (chareq(ch,ascii('?')) || chareq(ch,ascii('#')))
  #endif

# Wandelt ein Objekt in einen Pathname um.
  local object coerce_xpathname (object obj); # später

# Wandelt ein Objekt in einen nicht-Logical Pathname um.
  local object coerce_pathname (object obj); # später
#if !defined(LOGICAL_PATHNAMES)
  #define coerce_pathname(obj)  coerce_xpathname(obj)
#endif

# Liefert den Default-Pathname.
  local object defaults_pathname (void); # später

# Überprüft einen Default-Pathname.
# test_default_pathname(defaults)
# > defaults: Defaults-Argument
# < ergebnis: Wert des Defaults-Arguments, ein Pathname
# can trigger GC
  local object test_default_pathname (object defaults);
  local object test_default_pathname(defaults)
    var object defaults;
    {
      if (eq(defaults,unbound))
        # nicht angegeben -> Wert von *DEFAULT-PATHNAME-DEFAULTS* nehmen:
        return defaults_pathname();
      else
        # angegeben -> zu einem Pathname machen:
        return coerce_xpathname(defaults);
    }

# Fehlermeldung wegen illegalem Pathname-Argument.
# fehler_pathname_designator(thing);
# > thing: (fehlerhaftes) Argument
# > subr_self: Aufrufer (ein SUBR)
  nonreturning_function(global, fehler_pathname_designator, (object thing));
  global void fehler_pathname_designator(thing)
    var object thing;
    {
      pushSTACK(thing); # Wert für Slot DATUM von TYPE-ERROR
      pushSTACK(O(type_designator_pathname)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
      pushSTACK(thing);
      pushSTACK(TheSubr(subr_self)->name);
      fehler(type_error,
             GETTEXT("~: argument should be a string, symbol, file stream or pathname, not ~")
            );
    }

# Verfolgt eine Kette von Synonym-Streams, solange bis bei einem File-Stream
# angelangt.
# as_file_stream(stream)
# > stream: Builtin-Stream
# < stream: File-Stream
# > subr_self: Aufrufer (ein SUBR)
  local object as_file_stream (object stream);
  local object as_file_stream(stream)
    var object stream;
    {
      var object s = stream;
      loop {
        if (TheStream(s)->strmtype == strmtype_file)
          return s;
        if (!(TheStream(s)->strmtype == strmtype_synonym))
          break;
        s = Symbol_value(TheStream(stream)->strm_synonym_symbol);
        if (!builtin_stream_p(s))
          break;
      }
      fehler_pathname_designator(stream);
    }

# Signal an error if a file-stream does not have a file-name associated with it.
# test_file_stream_named(stream)
# > stream: File-Stream
# > subr_self: Aufrufer (ein SUBR)
  #define test_file_stream_named(stream)  \
    { if (nullp(TheStream(stream)->strm_file_truename)) \
        fehler_file_stream_unnamed(stream);             \
    }
  nonreturning_function(local, fehler_file_stream_unnamed, (object stream));
  local void fehler_file_stream_unnamed(stream)
    var object stream;
    {
      pushSTACK(stream); # Wert für Slot PATHNAME von FILE-ERROR
      pushSTACK(stream);
      pushSTACK(TheSubr(subr_self)->name);
      fehler(file_error,
             GETTEXT("~: filename for ~ is unknown")
            );
    }

#if defined(UNIX) || defined(MSDOS) || defined(RISCOS) || defined(WIN32_NATIVE)

#if defined(UNIX) || defined(MSDOS)
  #define slash  '/'
#endif
#ifdef WIN32_NATIVE
  #define slash  '\\'
#endif
#ifdef RISCOS
  #define slash  '.'
#endif

# UP: Wandelt eine Unix-Directory-Angabe in ein Pathname um.
# asciz_dir_to_pathname(path,encoding)
# > const char* path: path als ASCIZ-String
# > encoding: Encoding
# < ergebnis: als Pathname ohne Name und Typ
 #ifdef UNICODE
  local object asciz_dir_to_pathname (const char* path, object encoding);
  local object asciz_dir_to_pathname(const char* path, object encoding)
 #else
  #define asciz_dir_to_pathname(path,encoding)  asciz_dir_to_pathname_(path)
  local object asciz_dir_to_pathname_ (const char* path);
  local object asciz_dir_to_pathname_(const char* path)
 #endif
     {
       var object pathname;
       var const char* pathptr = path;
       var uintL len = 0; # Stringlänge
       # ASCIZ-Stringende suchen:
       until (*pathptr == 0) {
         pathptr++; len++;
       }
       # Sofern der String nicht schon mit '/' endet, wird ein '/' angefügt:
       if ((len>0) && (pathptr[-1] == slash)) {
         pathname = n_char_to_string(path,len,encoding);
       } else {
         var DYNAMIC_ARRAY(pathbuf,char,len+1);
         begin_system_call(); memcpy(pathbuf,path,len); end_system_call();
         pathbuf[len] = slash;
         pathname = n_char_to_string(pathbuf,len+1,encoding);
         FREE_DYNAMIC_ARRAY(pathbuf);
       }
       # und in ein Pathname umwandeln:
       return coerce_pathname(pathname);
     }

#endif

# Type for PARSE-NAMESTRING:
# State while the string is being parsed character by character.
  typedef struct {
    uintL index; # index (incl. offset)
    object FNindex; # index as a fixnum
    uintL count; # number of the remaining characters
  } zustand;

#ifdef LOGICAL_PATHNAMES

# Parsing of logical pathnames.

# Trennzeichen zwischen subdirs
#define slashp(c)  chareq(c,ascii(';'))

# Parses the name/type/version part (if subdirp=false) or a subdir part
# (if subdirp=true) of a logical pathname.
# parse_logical_word(&z,subdirp)
# > STACK_2: storage vector, a normal-simple-string
# > zustand z: start state
# < zustand z: updated
# < result: a normal-simple-string or :WILD or :WILD-INFERIORS or NIL
# can trigger GC
local object parse_logical_word (zustand* z, bool subdirp);
local object parse_logical_word(z,subdirp)
  var zustand* z;
  var bool subdirp;
  {
    ASSERT(sstring_normal_p(STACK_2));
    var zustand startz = *z; # Start-Zustand
    var chart ch;
    # Kommt eine Folge von alphanumerischen Zeichen oder '*',
    # keine zwei '*' adjazent (ausgenommen "**", falls subdirp),
    # und, falls subdirp, ein ';' ?
    var bool last_was_star = false;
    var bool seen_starstar = false;
    loop {
      if (z->count == 0)
        break;
      ch = TheSstring(STACK_2)->data[z->index]; # nächstes Character
      if (!legal_logical_word_char(ch)) {
        if (chareq(ch,ascii('*'))) {
          if (last_was_star) {
            if (subdirp && (z->index - startz.index == 1))
              seen_starstar = true;
            else
              break; # adjazente '*' sind verboten
          } else
            last_was_star = true;
        } else
          break;
      }
      # Character übergehen:
      z->index++; z->FNindex = fixnum_inc(z->FNindex,1); z->count--;
    }
    var uintL len = z->index - startz.index;
    if (subdirp) {
      if ((z->count == 0) || !slashp(ch)) {
        *z = startz; return NIL; # kein ';' -> kein subdir
      }
      # Character ';' übergehen:
      z->index++; z->FNindex = fixnum_inc(z->FNindex,1); z->count--;
    }
    if (len==0)
      return NIL;
    elif ((len==1) && chareq(TheSstring(STACK_2)->data[startz.index],ascii('*')))
      return S(Kwild);
    elif ((len==2) && seen_starstar)
      return S(Kwild_inferiors);
    else { # String bilden:
      var object result = allocate_string(len);
      # und füllen:
      {
        var const chart* ptr1 = &TheSstring(STACK_2)->data[startz.index];
        var chart* ptr2 = &TheSstring(result)->data[0];
        dotimespL(len,len, { *ptr2++ = up_case(*ptr1++); });
      }
      return result;
    }
  }

# Test whether a string is a digit sequence.
# all_digits(string)
# > string: a normal-simple-string
# < true if the string consists entirely of digits, false otherwise
local bool all_digits (object string);
local bool all_digits(string)
  var object string;
  {
    var uintL len = Sstring_length(string);
    if (len > 0) {
      var const chart* charptr = &TheSstring(string)->data[0];
      dotimespL(len,len, {
        var chart ch = *charptr++;
        var cint c = as_cint(ch);
        if (!((c >= '0') && (c <= '9')))
          return false;
      });
    }
    return true;
  }

# Attempt to parse a logical host name string, starting at a given state.
# parse_logical_host_prefix(&z,string)
# > string: storage vector, a normal-simple-string
# > zustand z: start state
# < zustand z: updated to point past the colon after the logical host
# < result: logical host, or NIL
# can trigger GC
local object parse_logical_host_prefix (zustand* zp, object string);
local object parse_logical_host_prefix(zp,string)
  var zustand* zp;
  var object string;
  {
    ASSERT(sstring_normal_p(string));
    var object host;
    var uintL startindex = zp->index;
    var chart ch;
    # a sequence of alphanumeric characters and then ':'
    loop {
      if (zp->count==0)
        return NIL; # string already ended -> no host
      ch = TheSstring(string)->data[zp->index]; # next character
      if (!legal_logical_word_char(ch))
        break;
      # go past alphanumeric character:
      zp->index++; zp->FNindex = fixnum_inc(zp->FNindex,1); zp->count--;
    }
    if (!chareq(ch,ascii(':')))
      return NIL; # no ':' -> no host
    # make host-string:
    {
      var uintL len = zp->index - startindex;
      host = allocate_string(len);
      # and fill it:
      if (len > 0) {
        var const chart* ptr1 = &TheSstring(string)->data[startindex];
        var chart* ptr2 = &TheSstring(host)->data[0];
        dotimespL(len,len, { *ptr2++ = up_case(*ptr1++); });
      }
    }
    # skip ':'
    zp->index++; zp->FNindex = fixnum_inc(zp->FNindex,1); zp->count--;
    return host;
  }

# Parses a logical pathname.
# parse_logical_pathnamestring(z)
# > STACK_1: storage vector, a normal-simple-string
# > STACK_0: freshly allocated logical pathname
# > zustand z: start state
# < STACK_0: same logical pathname, filled
# < result: number of remaining characters
# can trigger GC
local uintL parse_logical_pathnamestring (zustand z);
local uintL parse_logical_pathnamestring(z)
  var zustand z;
  {
    # Host-Specification parsen:
    {
      var zustand startz = z;
      var object host = parse_logical_host_prefix(&z,STACK_1);
      if (nullp(host)) {
        z = startz; # back to the start
        host = STACK_(3+2); # Default-Host
      } else { # enter host:
        TheLogpathname(STACK_0)->pathname_host = host;
      }
    }
    # Directory-Start eintragen:
    {
      var object new_cons = allocate_cons(); # neues Cons für Startpoint
      TheLogpathname(STACK_0)->pathname_directory = new_cons;
      pushSTACK(new_cons); # neues (last (pathname-directory Pathname))
    }
    # Stackaufbau: Datenvektor, Pathname, (last (pathname-directory Pathname)).
    # Subdirectories parsen:
    # Falls sofort ein ';' kommt, wird er übergangen, und es kommt :RELATIVE
    # (sonst :ABSOLUTE) als erstes subdir:
    if ((!(z.count == 0)) && slashp(TheSstring(STACK_2)->data[z.index])) {
      # Es kommt sofort ein ';'.
      # Character übergehen:
      z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
      Car(STACK_0) = S(Krelative); # Startpoint = :RELATIVE
    } else {
      # Es kommt nicht sofort ein ';'.
      Car(STACK_0) = S(Kabsolute); # Startpoint = :ABSOLUTE
    }
    loop {
      # Versuche, ein weiteres Unterdirectory zu parsen.
      var object subdir = parse_logical_word(&z,true);
      if (nullp(subdir))
        break;
      # (pathname-directory pathname) um Subdir verlängern:
      pushSTACK(subdir);
      var object new_cons = allocate_cons(); # neues Cons
      Car(new_cons) = popSTACK(); # = (cons subdir NIL)
      Cdr(STACK_0) = new_cons; # verlängert (pathname-directory Pathname)
      STACK_0 = new_cons; # neues (last (pathname-directory Pathname))
    }
    # Name parsen:
    {
      var object name = parse_logical_word(&z,false);
      TheLogpathname(STACK_1)->pathname_name = name;
      if ((z.count > 0) && chareq(TheSstring(STACK_2)->data[z.index],ascii('.'))) {
        var zustand z_name = z;
        # Character '.' übergehen:
        z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
        # Typ parsen:
        var object type = parse_logical_word(&z,false);
        TheLogpathname(STACK_1)->pathname_type = type;
        if (!nullp(type)) {
          if ((z.count > 0) && chareq(TheSstring(STACK_2)->data[z.index],ascii('.'))) {
            var zustand z_type = z;
            # Character '.' übergehen:
            z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
            # Version parsen:
            var object version = parse_logical_word(&z,false);
            if (eq(version,S(Kwild))) {
            } elif (equal(version,Symbol_name(S(Knewest)))) {
              version = S(Knewest);
            } elif (all_digits(version)) {
              pushSTACK(version); funcall(L(parse_integer),1); # version in Integer umwandeln
              version = value1;
            } else {
              version = NIL;
            }
            TheLogpathname(STACK_1)->pathname_version = version;
            if (nullp(version))
              z = z_type; # Character '.' wieder zurück
          } else {
            TheLogpathname(STACK_1)->pathname_version = NIL;
          }
        } else {
          z = z_name; # Character '.' wieder zurück
          TheLogpathname(STACK_1)->pathname_version = NIL;
        }
      } else {
        TheLogpathname(STACK_1)->pathname_type = NIL;
        TheLogpathname(STACK_1)->pathname_version = NIL;
      }
    }
    skipSTACK(1);
    return z.count;
  }

#undef slashp

# Erkennung eines logischen Hosts, vgl. CLtL2 S. 631
# (defun logical-host-p (host)
#   (and (simple-string-p host)
#        (gethash host sys::*logical-pathname-translations*) ; :test #'equalp !
#        t
# ) )
  local bool logical_host_p (object host);
  local bool logical_host_p(host)
    var object host;
    {
      return (simple_string_p(host)
              # No need to string-upcase host, because it's tested via EQUALP.
              && !eq(gethash(host,Symbol_value(S(logpathname_translations))),
                     nullobj
             )      );
    }

#endif

#ifdef PATHNAME_NOEXT
# Hilfsfunktion für PARSE-NAMESTRING:
# Spaltet einen String (beim letzten Punkt) in Name und Typ auf.
# split_name_type(skip);
# > STACK_0: Normal-Simple-String
# > skip: 1 falls ein Punkt an erster Stelle nicht aufspaltend wirken soll, 0 sonst
# < STACK_1: Name
# < STACK_0: Typ
# Erniedrigt STACK um 1
# can trigger GC
  local void split_name_type (uintL skip);
  local void split_name_type(skip)
    var uintL skip;
    {
      var object string = STACK_0;
      var uintL length = Sstring_length(string);
      # Nach dem letzten Punkt suchen:
      var uintL index = length;
      {
        var const chart* ptr = &TheSstring(string)->data[index];
        while (index>skip) {
          if (chareq(*--ptr,ascii('.'))) goto punkt;
          index--;
        }
      }
      # kein Punkt gefunden -> Typ := NIL
      pushSTACK(NIL);
      goto name_type_ok;
     punkt: # Punkt bei index gefunden
      # type := (substring string index)
      pushSTACK(subsstring(string,index,length));
      # name := (substring string 0 (1- index))
      STACK_1 = subsstring(STACK_1,0,index-1);
     name_type_ok: ;
    }
#endif

LISPFUN(parse_namestring,1,2,norest,key,3,\
        (kw(start),kw(end),kw(junk_allowed)) )
# (PARSE-NAMESTRING thing [host [defaults [:start] [:end] [:junk-allowed]]]),
# CLTL S. 414
  {
    # Stackaufbau: thing, host, defaults, start, end, junk-allowed.
    var bool junk_allowed;
    var bool host_was_null;
    var bool parse_logical = false;
    # 1. junk-allowed überprüfen:
    {
      var object obj = popSTACK(); # junk-allowed-Argument
      if (eq(obj,unbound))
        junk_allowed = false;
      else
        if (nullp(obj))
          junk_allowed = false;
        else
          junk_allowed = true;
    }
    # Stackaufbau: thing, host, defaults, start, end.
    # 2. Default-Wert für start ist 0:
    if (eq(STACK_1,unbound))
      STACK_1 = Fixnum_0;
    # 3. host überprüfen:
    #if HAS_HOST || defined(LOGICAL_PATHNAMES)
    {
      var object host = STACK_3;
      host_was_null = (eq(host,unbound) || nullp(host));
      #if HAS_HOST
      host = test_optional_host(host,false);
      #else
      host = test_optional_host(host);
      #endif
      if (nullp(host)) {
        # host := (PATHNAME-HOST defaults)
        var object defaults = test_default_pathname(STACK_2);
        #ifdef LOGICAL_PATHNAMES
        if (logpathnamep(defaults)) {
          parse_logical = true; host = TheLogpathname(defaults)->pathname_host;
        } else
        #endif
        {
          #if HAS_HOST
          host = ThePathname(defaults)->pathname_host;
          #else
          host = NIL;
          #endif
        }
      } else {
        host_was_null = false;
        #ifdef LOGICAL_PATHNAMES
        if (logical_host_p(host)) {
          parse_logical = true; host = string_upcase(host);
        }
        #endif
      }
      # if (nullp(host) && parse_logical) {
      #   pushSTACK(STACK_2);
      #   pushSTACK(STACK_4);
      #   pushSTACK(STACK_6);
      #   pushSTACK(S(parse_namestring));
      #   fehler(parse_error,
      #          GETTEXT("~(~ ~ ~): a logical pathname must contain host")
      #          );
      # }
      STACK_3 = host;
    }
    #else
    test_optional_host(STACK_3);
    host_was_null = true;
    #endif
    # 4. thing muss ein String sein:
    var object thing = STACK_4;
    if (xpathnamep(thing)) { # Pathname?
      value1 = thing; # 1. Wert thing
     fertig:
      value2 = STACK_1; mv_count=2; # 2. Wert start
      skipSTACK(5); return;
    }
    if (builtin_stream_p(thing)) { # Stream?
      thing = as_file_stream(thing);
      test_file_stream_named(thing);
      value1 = TheStream(thing)->strm_file_name; # 1. Wert: Filename
      goto fertig; # 2. Wert wie oben
    }
    # thing sollte nun wenigstens ein String oder Symbol sein:
    var bool thing_symbol = false;
    if (!stringp(thing)) {
      if (!symbolp(thing))
        fehler_pathname_designator(thing);
      thing = Symbol_name(thing); # Symbol -> Symbolname verwenden
      thing_symbol = true;
      STACK_4 = thing; # und in den Stack zurückschreiben
    }
    # thing = STACK_4 ist jetzt ein String.
    # Er wird durchlaufen.
    var zustand z; # laufender Zustand
    #ifdef PATHNAME_RISCOS
    # Hilfsvariablen zur Umsetzung eines new_thing-relativen FNindex
    # in einen thing-relativen FNindex.
    var object FNindex_limit = Fixnum_0;
    var sintL FNindex_offset = 0;
    var object FNindex_fallback;
    #endif
    {
      var object string; # String thing
      # Grenzen überprüfen, mit thing, start, end als Argumenten:
      var stringarg arg;
      pushSTACK(thing); pushSTACK(STACK_(1+1)); pushSTACK(STACK_(0+2));
      test_string_limits_ro(&arg);
      string = arg.string;
      z.index = arg.index;         # z.index = Wert des start-Arguments,
      z.count = arg.len;           # z.count = Anzahl der Characters.
      z.FNindex = fixnum(z.index); # z.FNindex = start-Index als Fixnum.
      z.index += arg.offset;
      #ifdef LOGICAL_PATHNAMES
      if (!parse_logical) {
        # Check whether *PARSE-NAMESTRING-ANSI* is true and the string
        # starts with a logical hostname.
        # (NB: ANSI CL specifies that we should look at the entire string, using
        # parse_logical_pathnamestring, not only parse_logical_host_prefix.)
        if (!nullp(Symbol_value(S(parse_namestring_ansi)))) {
          # Coerce string to be a normal-simple-string.
          SstringDispatch(string,
            {},
            { string = subsstring(string,z.index,z.index+z.count); z.index = 0; }
            );
          var zustand tmp = z;
          var object host = parse_logical_host_prefix(&tmp,string);
          DOUT("parse-namestring: ",string);
          DOUT("parse-namestring: ",host);
          if (!nullp(host)
              # Test whether the given hostname is valid. This is not
              # strictly what ANSI specifies, but is better than giving
              # an error for Win32 pathnames like "C:\\FOOBAR".
              && logical_host_p(host)
             )
            parse_logical = true;
        }
      }
      #endif
      # Coerce string to be a normal-simple-string.
      if (thing_symbol && !parse_logical) {
        #if defined(PATHNAME_UNIX) || defined(PATHNAME_OS2) || defined(PATHNAME_WIN32) || defined(PATHNAME_RISCOS)
        # Betriebssystem mit Vorzug für Kleinbuchstaben
        string = subsstring(string,z.index,z.index+z.count); z.index = 0; # ja -> mit STRING-DOWNCASE umwandeln
        nstring_downcase(&TheSstring(string)->data[0],Sstring_length(string));
        #endif
        #ifdef PATHNAME_AMIGAOS
        # Betriebssystem mit Vorzug für Capitalize
        string = subsstring(string,z.index,z.index+z.count); z.index = 0; # ja -> mit STRING-CAPITALIZE umwandeln
        nstring_capitalize(&TheSstring(string)->data[0],Sstring_length(string));
        #endif
      }
      SstringDispatch(string,
        {},
        { string = subsstring(string,z.index,z.index+z.count); z.index = 0; }
        );
      pushSTACK(string);
    }
    #ifdef LOGICAL_PATHNAMES
    if (parse_logical) {
      pushSTACK(allocate_logpathname());
      # Stackaufbau: ..., Datenvektor, Pathname.
      var uintL remaining = parse_logical_pathnamestring(z);
      z.index += z.count-remaining; z.FNindex = fixnum_inc(z.FNindex,z.count-remaining); z.count = remaining;
    } else
    #endif
    {
      #ifdef PATHNAME_RISCOS
        # If the string starts with a system variable in <...> syntax,
        # then perform the substitution
        # (string-concat "<" var ">" tail) --> (string-concat (sys::getenv var) tail).
        if ((!(z.count==0)) && chareq(TheSstring(STACK_0)->data[z.index],ascii('<'))) {
          var zustand startz = z; # Start-Zustand
          var chart ch;
          # Character '<' übergehen:
          z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
          loop {
            if (z.count==0)
              goto no_envvar;
            ch = TheSstring(STACK_0)->data[z.index]; # nächstes Character
            if (chareq(ch,ascii('>')))
              break;
            if (!(graphic_char_p(ch) && !chareq(ch,ascii('*')) && !chareq(ch,ascii('#'))))
              goto no_envvar;
            # gültiges Character übergehen:
            z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
          }
          FNindex_fallback = z.FNindex;
          # Character '>' übergehen:
          z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
          # Environment-Variable als Simple-String bauen:
          if (z.index - startz.index - 2 == 0)
            goto no_envvar;
          {
            var object envvar = subsstring(STACK_0,startz.index+1,z.index-1);
            # Deren Wert holen:
            with_sstring_0(envvar,O(misc_encoding),envvar_asciz, {
              begin_system_call();
              var const char* envval = getenv(envvar_asciz);
              end_system_call();
              if (envval==NULL) {
                pushSTACK(envvar);
                pushSTACK(S(parse_namestring));
                fehler(parse_error,
                       GETTEXT("~: there is no environment variable ~")
                      );
              }
              pushSTACK(asciz_to_string(envval,O(misc_encoding))); # Wert der Variablen als String
            });
          }
          # Reststück bilden:
          pushSTACK(subsstring(STACK_1,z.index,z.index+z.count));
          # Beides zusammenhängen, thing ersetzen:
          {
            var uintL envval_len = Sstring_length(STACK_1);
            var object new_thing = string_concat(2);
            STACK_(4+1) = STACK_0 = new_thing;
            # Der 2. Wert FNindex muss nachher noch modifiziert werden.
            FNindex_limit = fixnum(envval_len);
            FNindex_offset = (sintL)posfixnum_to_L(z.FNindex) - (sintL)envval_len;
            z.index = 0; z.count = Sstring_length(new_thing); z.FNindex = Fixnum_0;
          }
          goto envvar_ok;
         no_envvar: # keine Environment-Variable
          z = startz; # zum Start zurück
        }
       envvar_ok: ;
      #endif
      pushSTACK(allocate_pathname());
      # Stackaufbau: ..., Datenvektor, Pathname.
      # Trennzeichen zwischen subdirs ist unter MSDOS sowohl '\' als auch '/':
      #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
        #define slashp(c)  (chareq(c,ascii('\\')) || chareq(c,ascii('/')))
      #endif
      #if defined(PATHNAME_UNIX) || defined(PATHNAME_AMIGAOS)
        #define slashp(c)  chareq(c,ascii('/'))
      #endif
      #ifdef PATHNAME_RISCOS
        #define slashp(c)  chareq(c,ascii('.'))
      #endif
      #if HAS_HOST
        # Host-Specification parsen:
        {
          var object host;
          {
            var zustand startz = z; # Start-Zustand
            var chart ch;
            #if defined(PATHNAME_RISCOS)
              # Kommt eine Folge von Zeichen, eingeschlossen in '-',
              # oder eine Folge von Zeichen und dann eine ':' ?
              if (z.count==0) goto no_hostspec; # String schon zu Ende -> kein Host
              ch = TheSstring(STACK_1)->data[z.index]; # nächstes Character
              if (chareq(ch,ascii('-'))) {
                # '-' übergehen:
                z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
                loop {
                  if (z.count==0)
                    goto no_hostspec; # String schon zu Ende -> kein Host
                  ch = TheSstring(STACK_1)->data[z.index]; # nächstes Character
                  if (chareq(ch,ascii('-')))
                    break;
                  if (!legal_hostchar(ch))
                    goto no_hostspec;
                  # gültiges Character übergehen:
                  z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
                }
                # Host-String bilden:
                if (z.index - startz.index - 1 == 0)
                  goto no_hostspec;
                host = subsstring(STACK_1,startz.index+1,z.index);
              } else {
                loop {
                  if (!legal_hostchar(ch))
                    goto no_hostspec;
                  # gültiges Character übergehen:
                  z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
                  if (z.count==0)
                    goto no_hostspec; # String schon zu Ende -> kein Host
                  ch = TheSstring(STACK_1)->data[z.index]; # nächstes Character
                  if (chareq(ch,ascii(':')))
                    break;
                }
                # Host-String bilden:
                host = subsstring(STACK_1,startz.index,z.index);
              }
              # Character '-' bzw. ':' übergehen:
              z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              goto hostspec_ok;
            #elif defined(PATHNAME_WIN32)
              # Look for two slashes, then a sequence of characters.
              if (z.count==0) goto no_hostspec;
              ch = TheSstring(STACK_1)->data[z.index];
              if (!slashp(ch)) goto no_hostspec;
              z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              if (z.count==0) goto no_hostspec;
              ch = TheSstring(STACK_1)->data[z.index];
              if (!slashp(ch)) goto no_hostspec;
              z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              loop {
                if (z.count==0)
                  break;
                ch = TheSstring(STACK_1)->data[z.index];
                if (!legal_hostchar(ch))
                  break;
                # Skip past valid host char.
                z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              }
              # Create host string.
              if (z.index - startz.index - 2 == 0)
                goto no_hostspec;
              host = subsstring(STACK_1,startz.index+2,z.index);
              # Note: The next character in the string is not a letter or '*';
              # therefore the device of the resulting pathname will be NIL.
              goto hostspec_ok;
            #else
              # Kommt eine Folge von alphanumerischen Zeichen und dann ein ':' bzw. '::' ?
              loop {
                if (z.count==0)
                  goto no_hostspec; # String schon zu Ende -> kein Host
                ch = TheSstring(STACK_1)->data[z.index]; # nächstes Character
                if (!alphanumericp(ch))
                  break;
                # alphanumerisches Character übergehen:
                z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              }
              if (!chareq(ch,ascii(':')))
                goto no_hostspec; # kein ':' -> kein Host
              # Host-String bilden:
              host = subsstring(STACK_1,startz.index,z.index);
              # Character ':' übergehen:
              z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              goto hostspec_ok;
            #endif
           no_hostspec: # keine Host-Specification
            z = startz; # zum Start zurück
            host = STACK_(3+2); # Default-Host
          }
         hostspec_ok:
          # Host eintragen:
          ThePathname(STACK_0)->pathname_host = host;
        }
      #endif
      #if HAS_DEVICE
        #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
          # Einbuchstabige Device-Specification parsen:
          {
            var object device = NIL; # Device := NIL
            # Drive-Specification parsen:
            # Kommt ein Buchstabe ('*','A'-'Z','a'-'z') und dann ein ':' ?
            {
              var zustand startz = z; # Start-Zustand
              var chart ch;
              if (z.count==0)
                goto no_drivespec; # String schon zu Ende ?
              ch = TheSstring(STACK_1)->data[z.index]; # nächstes Character
              ch = up_case(ch); # als Großbuchstabe
              if (chareq(ch,ascii('*'))) {
                # ch = '*' -> Device := :WILD
                device = S(Kwild);
              } elif ((as_cint(ch) >= 'A') && (as_cint(ch) <= 'Z')) {
                # 'A' <= ch <= 'Z' -> Device := "ch"
                var object string = allocate_string(1); # String der Länge 1
                TheSstring(string)->data[0] = ch; # mit ch als einzigem Buchstaben
                device = string;
              } else
                goto no_device;
              # Device OK, Character übergehen:
              z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              if (z.count==0)
                goto no_drivespec; # String schon zu Ende ?
              ch = TheSstring(STACK_1)->data[z.index]; # nächstes Character
              ch = up_case(ch); # als Großbuchstabe
             no_device:
              # mit Doppelpunkt abgeschlossen?
              if (!chareq(ch,ascii(':')))
                goto no_drivespec;
              # Character übergehen:
              z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              goto drivespec_ok;
             no_drivespec:
              # Es ist nicht gelungen, eine Drive-Specification zu parsen.
              z = startz; # Start-Zustand wiederherstellen
              device = NIL; # Device := NIL
            }
           drivespec_ok:
            ThePathname(STACK_0)->pathname_device = device; # Device eintragen
          }
        #endif
        #ifdef PATHNAME_AMIGAOS
          # Device-Specification parsen:
          {
            var object device;
            # Kommt eine nichtleere Folge von alphanumerischen Zeichen und dann ein ':' ?
            {
              var zustand startz = z; # Start-Zustand
              var chart ch;
              loop {
                if (z.count==0)
                  goto no_devicespec; # String schon zu Ende -> kein Device
                ch = TheSstring(STACK_1)->data[z.index]; # nächstes Character
                if (!legal_namechar(ch))
                  break;
                # alphanumerisches Character übergehen:
                z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              }
              if (!chareq(ch,ascii(':')))
                goto no_devicespec; # kein ':' -> kein Device
              if (z.index==startz.index)
                goto no_devicespec; # ':' am Anfang ist kein Device
              # Device-String bilden:
              device = subsstring(STACK_1,startz.index,z.index);
              # Character ':' nicht übergehen; das ergibt dann :ABSOLUTE.
              goto devicespec_ok;
             no_devicespec: # keine Device-Specification
              z = startz; # zum Start zurück
              device = NIL; # Device NIL
            }
           devicespec_ok:
            # Device eintragen:
            ThePathname(STACK_0)->pathname_device = device;
          }
        #endif
        #ifdef PATHNAME_RISCOS
          # Device-Specification parsen:
          {
            var object device;
            # Kommt ein ':', eine nichtleere Folge von Zeichen und dann ein '.' ?
            {
              var zustand startz = z; # Start-Zustand
              var chart ch;
              if (z.count==0)
                goto no_devicespec; # String schon zu Ende -> kein Device
              ch = TheSstring(STACK_1)->data[z.index]; # nächstes Character
              if (!chareq(ch,ascii(':')))
                goto no_devicespec; # kein ':' -> kein Device
              # Character ':' übergehen:
              z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              loop {
                if (z.count==0)
                  goto no_devicespec; # String schon zu Ende -> kein Device
                ch = TheSstring(STACK_1)->data[z.index]; # nächstes Character
                if (!(legal_namechar(ch) && !chareq(ch,ascii('*')) && !singlewild_char_p(ch)))
                  break;
                # gültiges Character übergehen:
                z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              }
              if (!chareq(ch,ascii('.')))
                goto no_devicespec; # kein '.' -> kein Device
              # Device-String bilden:
              if (z.index - startz.index - 1 == 0)
                goto no_devicespec;
              device = subsstring(STACK_1,startz.index+1,z.index);
              # Character '.' übergehen:
              z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              goto devicespec_ok;
             no_devicespec: # keine Device-Specification
              z = startz; # zum Start zurück
              device = NIL; # Device NIL
            }
           devicespec_ok:
            # Device eintragen:
            ThePathname(STACK_0)->pathname_device = device;
          }
        #endif
      #endif
      # Directory-Start eintragen:
      {
        var object new_cons = allocate_cons(); # neues Cons für Startpoint
        ThePathname(STACK_0)->pathname_directory = new_cons;
        pushSTACK(new_cons); # neues (last (pathname-directory Pathname))
      }
      # Stackaufbau: ..., Datenvektor, Pathname, (last (pathname-directory Pathname)).
      # Subdirectories parsen:
      {
        #if defined(USER_HOMEDIR) && defined(PATHNAME_UNIX)
          # Falls sofort ein '~' kommt, wird bis zum nächsten '/' oder Stringende
          # ein Username gelesen und das Home-Directory dieses Users eingesetzt:
          if ((!(z.count == 0)) && chareq(TheSstring(STACK_2)->data[z.index],ascii('~'))) {
            # Es kommt sofort ein '~'.
            # Character übergehen:
            z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
            var object userhomedir; # Pathname des User-Homedir
            # nächsten '/' suchen:
            var uintL charcount = 0;
            {
              var const chart* charptr = &TheSstring(STACK_2)->data[z.index];
              var uintL count;
              dotimesL(count,z.count, {
                if (chareq(*charptr++,ascii('/')))
                  break;
                charcount++;
              });
            }
            # Username hat charcount Zeichen
            if (charcount==0) {
              userhomedir = O(user_homedir); # nur '~' -> User-Homedir
            } else {
              # Username bauen:
              var object username = subsstring(STACK_2,z.index,z.index+charcount);
              # Dessen Home-Directory aus dem Passwort-File holen:
              with_sstring_0(username,O(misc_encoding),username_asciz, {
                begin_system_call();
                errno = 0;
                var struct passwd * userpasswd = getpwnam(username_asciz);
                if (userpasswd == (struct passwd *)NULL) { # erfolglos?
                  if (!(errno==0)) { OS_error(); } # Error melden
                  end_system_call();
                  # sonst: Fehler
                  pushSTACK(username);
                  pushSTACK(S(parse_namestring));
                  fehler(parse_error,
                         GETTEXT("~: there is no user named ~")
                        );
                }
                end_system_call();
                userhomedir = asciz_dir_to_pathname(userpasswd->pw_dir,O(misc_encoding)); # Homedir als Pathname
              });
            }
            # Directory aus dem Pathname userhomedir kopieren:
            # (copy-list dir) = (nreconc (reverse dir) nil),
            # danach dessen letztes Cons merken.
            userhomedir = reverse(ThePathname(userhomedir)->pathname_directory);
            userhomedir = nreconc(userhomedir,NIL);
            ThePathname(STACK_1)->pathname_directory = userhomedir;
            while (mconsp(Cdr(userhomedir))) { userhomedir = Cdr(userhomedir); }
            STACK_0 = userhomedir;
            # username-Characters übergehen:
            z.index += charcount; z.FNindex = fixnum_inc(z.FNindex,charcount); z.count -= charcount;
            # Falls der String zu Ende ist: fertig,
            # sonst kommt sofort ein '/', es wird übergangen:
            if (z.count==0) {
              pushSTACK(NIL); pushSTACK(NIL); goto after_name_type; # Name und Typ := NIL
            }
            # Character übergehen:
            z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
          } else
        #endif
        #if defined(PATHNAME_UNIX) && 0 # Wozu braucht man das, außer für $HOME ?
          # Falls sofort ein '$' kommt, wird bis zum nächsten '/' oder Stringende
          # eine Environment-Variable gelesen und ihr Wert eingesetzt:
          if ((!(z.count == 0)) && chareq(TheSstring(STACK_2)->data[z.index],ascii('$'))) {
            # Es kommt sofort ein '$'.
            # Character übergehen:
            z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
            var object envval_dir;
            # nächsten '/' suchen:
            var uintL charcount = 0;
            {
              var const chart* charptr = &TheSstring(STACK_2)->data[z.index];
              var uintL count;
              dotimesL(count,z.count, {
                if (chareq(*charptr++,ascii('/')))
                  break;
                charcount++;
              });
            }
            # Environment-Variable hat charcount Zeichen.
            {
              var object envvar = subsstring(STACK_2,z.index,z.index+charcount);
              # Deren Wert holen:
              with_sstring_0(envvar,O(misc_encoding),envvar_asciz, {
                begin_system_call();
                var const char* envval = getenv(envvar_asciz);
                end_system_call();
                if (envval==NULL) {
                  pushSTACK(envvar);
                  pushSTACK(S(parse_namestring));
                  fehler(parse_error,
                         GETTEXT("~: there is no environment variable ~")
                        );
                }
                envval_dir = asciz_dir_to_pathname(envval,O(misc_encoding)); # Wert der Variablen als Pathname
              });
            }
            # Directory aus dem Pathname envval_dir kopieren:
            # (copy-list dir) = (nreconc (reverse dir) nil),
            # danach dessen letztes Cons merken.
            envval_dir = reverse(ThePathname(envval_dir)->pathname_directory);
            envval_dir = nreconc(envval_dir,NIL);
            ThePathname(STACK_1)->pathname_directory = envval_dir;
            while (mconsp(Cdr(envval_dir))) { envval_dir = Cdr(envval_dir); }
            STACK_0 = envval_dir;
            # envvar-Characters übergehen:
            z.index += charcount; z.FNindex = fixnum_inc(z.FNindex,charcount); z.count -= charcount;
            # Falls der String zu Ende ist: fertig,
            # sonst kommt sofort ein '/', es wird übergangen:
            if (z.count==0) {
              pushSTACK(NIL); pushSTACK(NIL); goto after_name_type; # Name und Typ := NIL
            }
            # Character übergehen:
            z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
          } else
        #endif
        #if defined(PATHNAME_UNIX) || defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
          # Falls sofort ein '\' bzw. '/' kommt, wird er übergangen, und es kommt
          # :ABSOLUTE (sonst :RELATIVE) als erstes subdir:
          if ((!(z.count == 0)) && slashp(TheSstring(STACK_2)->data[z.index])) {
            # Es kommt sofort ein '\' bzw. '/'.
            # Character übergehen:
            z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
            Car(STACK_0) = S(Kabsolute); # Startpoint = :ABSOLUTE
          } else {
            # Es kommt nicht sofort ein '\' bzw. '/'.
            Car(STACK_0) = S(Krelative); # Startpoint = :RELATIVE
          }
        #endif
        #ifdef PATHNAME_AMIGAOS
          # Falls sofort ein ':' kommt, wird er übergangen, und es kommt
          # :ABSOLUTE (sonst :RELATIVE) als erstes subdir:
          if ((!(z.count == 0)) && chareq(TheSstring(STACK_2)->data[z.index],ascii(':'))) {
            # Es kommt sofort ein ':'.
            # Character übergehen:
            z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
            Car(STACK_0) = S(Kabsolute); # directory = (:ABSOLUTE)
          } else {
            # Es kommt nicht sofort ein ':'.
            Car(STACK_0) = S(Krelative); # directory = (:RELATIVE)
          }
        #endif
        #ifdef PATHNAME_RISCOS
          # Präfix '$.' oder '&.' oder '@.' oder '%.' oder '\.' parsen.
          if ((z.count >= 2) && chareq(TheSstring(STACK_2)->data[z.index+1],ascii('.'))) {
            switch (as_cint(TheSstring(STACK_2)->data[z.index])) {
              case '$': Car(STACK_0) = S(Kroot); break; # directory = (:ABSOLUTE :ROOT)
              case '&': Car(STACK_0) = S(Khome); break; # directory = (:ABSOLUTE :HOME)
              case '@': Car(STACK_0) = S(Kcurrent); break; # directory = (:ABSOLUTE :CURRENT)
              case '%': Car(STACK_0) = S(Klibrary); break; # directory = (:ABSOLUTE :LIBRARY)
              case '\\': Car(STACK_0) = S(Kprevious); break; # directory = (:ABSOLUTE :PREVIOUS)
              default: goto prefix_relative;
            }
            # Präfix übergehen:
            z.index+=2; z.FNindex = fixnum_inc(z.FNindex,2); z.count-=2;
            # (pathname-directory pathname) um ein Cons (:ABSOLUTE) verlängern:
            var object new_cons = allocate_cons(); # neues Cons
            Car(new_cons) = S(Kabsolute); Cdr(new_cons) = STACK_0;
            ThePathname(STACK_1)->pathname_directory = new_cons;
          } else {
           prefix_relative:
            Car(STACK_0) = S(Krelative); # directory = (:RELATIVE)
          }
        #endif
        #if !defined(PATHNAME_RISCOS)
          loop {
            # Versuche, ein weiteres Unterdirectory zu parsen.
            #ifdef PATHNAME_NOEXT
              {
                var uintL z_start_index = z.index; # Index beim Start
                loop {
                  var chart ch;
                  if (z.count == 0)
                    break;
                  ch = TheSstring(STACK_2)->data[z.index]; # nächstes Character
                  if (!legal_namechar(ch)) # gültiges Character ?
                    break;
                  # ja -> Teil des Namens
                  # Character übergehen:
                  z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
                }
                # Ende des Namens erreicht.
                # Name := Teilstring von STACK_2 von z_start_index (einschließlich)
                #                                bis z.index (ausschließlich).
                var object string = subsstring(STACK_2,z_start_index,z.index);
                # Name fertig.
                pushSTACK(string);
              }
              # Kommt sofort ein '/' bzw. '\', so war es ein Unterdirectory,
              # sonst ist der Pathname beendet:
              if ((z.count==0) || !slashp(TheSstring(STACK_3)->data[z.index]))
                # Nein -> war der Name und kein Subdir.
                break;
              # Es kommt ein '/' bzw. '\'. Character übergehen:
              z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              # Stackaufbau: ...,
              #   Datenvektor, Pathname, (last (pathname-directory Pathname)),
              #   subdir.
              #ifdef PATHNAME_AMIGAOS
              # War es '' ?
              if (equal(STACK_0,O(leer_string))) {
                STACK_0 = S(Kparent); # ja -> durch :PARENT ersetzen
              } else
              #endif
              # War es '**' oder '...' ?
              if (equal(STACK_0,O(wildwild_string)) || equal(STACK_0,O(punktpunktpunkt_string))) {
                STACK_0 = S(Kwild_inferiors); # ja -> durch :WILD-INFERIORS ersetzen
              }
            #endif
            # (pathname-directory pathname) um Subdir STACK_0 verlängern:
            var object new_cons = allocate_cons(); # neues Cons
            Car(new_cons) = popSTACK(); # = (cons subdir NIL)
            Cdr(STACK_0) = new_cons; # verlängert (pathname-directory Pathname)
            STACK_0 = new_cons; # neues (last (pathname-directory Pathname))
          }
        #else # defined(PATHNAME_RISCOS)
          pushSTACK(unbound); # maybe-name
          # Stackaufbau: ..., Datenvektor, Pathname, (last (pathname-directory Pathname)),
          #              maybe-name.
          loop {
            # Versuche, ein weiteres Unterdirectory zu parsen.
            # Maybe-Name = die letzte gelesene Komponente in
            # { { legal-wild char }+ | empty } '.'  Syntax.
            # Ob ein weiteres subdir oder der Name, wird sich erst noch
            # entscheiden.
            # Kommt '^.' ?
            if (!nullp(STACK_0)
                && (z.count >= 2)
                && chareq(TheSstring(STACK_3)->data[z.index],ascii('^'))
                && slashp(TheSstring(STACK_3)->data[z.index+1])
               ) {
              # beide Characters übergehen:
              z.index+=2; z.FNindex = fixnum_inc(z.FNindex,2); z.count-=2;
              pushSTACK(S(Kparent)); # :PARENT
            } else {
              # Versuche, normale  { legal-wild char }+  Syntax zu parsen:
              var uintL z_start_index = z.index; # Index beim Start des Namens
              loop {
                var chart ch;
                if (z.count == 0)
                  break;
                ch = TheSstring(STACK_3)->data[z.index]; # nächstes Character
                if (!legal_namechar(ch)) # gültiges Character ?
                  break;
                # ja -> Teil des Namens
                # Character übergehen:
                z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              }
              # Ende des Namens erreicht.
              # Name := Teilstring von STACK_3 von z_start_index (einschließlich)
              #                                bis z.index (ausschließlich).
              var object string;
              if (z.index - z_start_index == 0)
                string = NIL; # "" wird zu NIL
              else
                string = subsstring(STACK_3,z_start_index,z.index);
              # Name fertig.
              if (nullp(STACK_0)
                  || (z.count==0)
                  || !slashp(TheSstring(STACK_3)->data[z.index])
                 ) {
                pushSTACK(string); break;
              }
              # Character '.' übergehen:
              z.index++; z.FNindex = fixnum_inc(z.FNindex,1); z.count--;
              pushSTACK(string);
            }
            if (!eq(STACK_1,unbound)) {
              # (pathname-directory pathname) um Subdir STACK_1 verlängern:
              var object new_cons = allocate_cons(); # neues Cons
              Car(new_cons) = STACK_1; # = (cons subdir NIL)
              Cdr(STACK_2) = new_cons; # verlängert (pathname-directory Pathname)
              STACK_2 = new_cons; # neues (last (pathname-directory Pathname))
            }
            STACK_1 = STACK_0; skipSTACK(1); # maybe-name := subdir
          }
          if (eq(STACK_1,unbound)) {
            STACK_1 = STACK_0; STACK_0 = NIL;
          }
          # Stackaufbau: ..., Datenvektor, Pathname, (last (pathname-directory Pathname)),
          #              name, type.
          # In gewissen Fällen hört die Directory-Angabe nicht nach dem
          # vorletzten Punkt, sondern nach dem letzten Punkt auf:
          elif (eq(STACK_1,S(Kparent)) # z.B. "bar.^.foo"
                || (nullp(STACK_0) && !nullp(STACK_1)) # z.B. "foo.bar."
               ) {
            # (pathname-directory pathname) um Subdir STACK_1 verlängern:
            var object new_cons = allocate_cons(); # neues Cons
            Car(new_cons) = STACK_1; # = (cons subdir NIL)
            Cdr(STACK_2) = new_cons; # verlängert (pathname-directory Pathname)
            STACK_2 = new_cons; # neues (last (pathname-directory Pathname))
            STACK_1 = STACK_0; # name := type
            STACK_0 = NIL;     # type := NIL
          }
        #endif
        #if defined(PATHNAME_RISCOS)
          # Stackaufbau: ...,
          #   Datenvektor, Pathname, (last (pathname-directory Pathname)),
          #   name, type.
          # Name und Typ in Pathname eintragen:
          {
            var object type = popSTACK();
            var object name = popSTACK();
            skipSTACK(1); # Directory ist schon eingetragen
            var object pathname = STACK_0;
            ThePathname(pathname)->pathname_name = name;
            ThePathname(pathname)->pathname_type = type;
          }
        #endif
        #ifdef PATHNAME_NOEXT
          # Stackaufbau: ..., Datenvektor, Pathname, (last (pathname-directory Pathname)),
          #              string.
          split_name_type(0); # String STACK_0 in Name und Typ aufspalten
         after_name_type:
          # Stackaufbau: ..., Datenvektor, Pathname, (last (pathname-directory Pathname)),
          #              name, type.
          # Name und Typ in Pathname eintragen:
          {
            var object type = popSTACK();
            var object name = popSTACK();
            skipSTACK(1); # Directory ist schon eingetragen
            # name="" durch Name=NIL ersetzen:
            if (equal(name,O(leer_string)))
              name = NIL;
            var object pathname = STACK_0;
            ThePathname(pathname)->pathname_name = name;
            ThePathname(pathname)->pathname_type = type;
          }
        #endif
      }
      #undef slashp
    }
    # Pathname fertig.
    # Stackaufbau: ..., Datenvektor, Pathname.
    if (!junk_allowed)
      # Überprüfen, ob keine Zeichen mehr übrig sind:
      if (!(z.count == 0)) {
        pushSTACK(z.FNindex); # letzter Index
        pushSTACK(STACK_(4+2+1)); # thing
        pushSTACK(S(parse_namestring));
        fehler(parse_error,
              GETTEXT("~: syntax error in filename ~ at position ~")
             );
      }
    #if HAS_HOST || defined(LOGICAL_PATHNAMES)
    # Check that if a :host argument was present and the parsed pathname has
    # a host component, they agree.
    if (!host_was_null) {
      #ifdef LOGICAL_PATHNAMES
      if (parse_logical) {
        var object parsed_host = TheLogpathname(STACK_0)->pathname_host;
        if (!nullp(parsed_host))
          if (!equal(STACK_(3+2),parsed_host)) {
            pushSTACK(STACK_0);
            pushSTACK(parsed_host);
            pushSTACK(STACK_(3+2+2));
            pushSTACK(S(parse_namestring));
            fehler(error,
                   GETTEXT("~: hosts ~ and ~ of ~ should coincide")
                  );
          }
      } else
      #endif
      {
        #if HAS_HOST
        var object parsed_host = ThePathname(STACK_0)->pathname_host;
        if (!nullp(parsed_host))
          if (!equal(STACK_(3+2),parsed_host)) {
            pushSTACK(STACK_0);
            pushSTACK(parsed_host);
            pushSTACK(STACK_(3+2+2));
            pushSTACK(S(parse_namestring));
            fehler(error,
                   GETTEXT("~: hosts ~ and ~ of ~ should coincide")
                  );
          }
        #endif
      }
    }
    #endif
    value1 = STACK_0; # Pathname als 1. Wert
    #ifdef PATHNAME_RISCOS
    if (as_oint(z.FNindex) >= as_oint(FNindex_limit)) {
      # FNindex von new_thing nach thing umrechnen:
      value2 = fixnum_inc(z.FNindex,FNindex_offset);
    } else {
      # FNindex zeigt in den ersetzten (!) String envval. Was bleibt
      # uns als Index anderes übrig als der Start-Index?
      # (Nicht ganz korrekt freilich: Hätte das Parsen wirklich dort
      # aufgehört, würde value1 anders aussehen!)
      # Zum Beispiel ein Index in das Innere des <...>-Konstruktes.
      # (Auch das ist nicht ganz korrekt, kommt der Sache aber näher.)
      value2 = FNindex_fallback;
    }
    #else
    value2 = z.FNindex; # Index als 2. Wert
    #endif
    mv_count=2; # 2 Werte
    skipSTACK(5+2); return;
  }

# UP: Wandelt ein Objekt in einen Pathname um.
# coerce_xpathname(object)
# > object: Objekt
# < ergebnis: (PATHNAME Objekt)
# can trigger GC
  local object coerce_xpathname (object obj);
  local object coerce_xpathname(obj)
    var object obj;
    {
      if (xpathnamep(obj)) {
        # Bei Pathnames ist nichts zu tun.
        return obj;
      } else {
        # sonst: PARSE-NAMESTRING aufrufen:
        pushSTACK(subr_self); # subr_self retten (für spätere Fehlermeldungen)
        pushSTACK(obj); funcall(L(parse_namestring),1);
        subr_self = popSTACK();
        return value1;
      }
    }

LISPFUNN(pathname,1)
# (PATHNAME pathname), CLTL S. 413
  {
    value1 = coerce_xpathname(popSTACK()); mv_count=1;
  }

LISPFUN(pathnamehost,1,0,norest,key,1, (kw(case)))
# (PATHNAME-HOST pathname [:case]), CLTL S. 417, CLtL2 S. 644
  {
    var object pathname = coerce_xpathname(STACK_1);
    #ifdef LOGICAL_PATHNAMES
    if (logpathnamep(pathname)) {
      value1 = TheLogpathname(pathname)->pathname_host; mv_count=1;
    } else
    #endif
    {
      #if HAS_HOST
      var object erg = ThePathname(pathname)->pathname_host;
      value1 = (eq(STACK_0,S(Kcommon)) ? common_case(erg) : erg);
      mv_count=1; # host als Wert
      #else
      value1 = NIL; mv_count=1; # NIL als Wert
      #endif
    }
    skipSTACK(2);
  }

LISPFUN(pathnamedevice,1,0,norest,key,1, (kw(case)))
# (PATHNAME-DEVICE pathname [:case]), CLTL S. 417, CLtL2 S. 644
  {
    var object pathname = coerce_xpathname(STACK_1);
    #ifdef LOGICAL_PATHNAMES
    if (logpathnamep(pathname)) {
      value1 = NIL; mv_count=1;
    } else
    #endif
    {
      #if HAS_DEVICE
      var object erg = ThePathname(pathname)->pathname_device;
      value1 = (eq(STACK_0,S(Kcommon)) ? common_case(erg) : erg);
      mv_count=1; # device als Wert
      #else
      value1 = NIL; mv_count=1; # NIL als Wert
      #endif
    }
    skipSTACK(2);
  }

LISPFUN(pathnamedirectory,1,0,norest,key,1, (kw(case)))
# (PATHNAME-DIRECTORY pathname [:case]), CLTL S. 417, CLtL2 S. 644
  {
    var object pathname = coerce_xpathname(STACK_1);
    #ifdef LOGICAL_PATHNAMES
    if (logpathnamep(pathname)) {
      value1 = TheLogpathname(pathname)->pathname_directory;
    } else
    #endif
    {
      var object erg = ThePathname(pathname)->pathname_directory;
      value1 = (eq(STACK_0,S(Kcommon)) ? subst_common_case(erg) : erg);
    }
    mv_count=1; # directory als Wert
    skipSTACK(2);
  }

LISPFUN(pathnamename,1,0,norest,key,1, (kw(case)))
# (PATHNAME-NAME pathname [:case]), CLTL S. 417, CLtL2 S. 644
  {
    var object pathname = coerce_xpathname(STACK_1);
    #ifdef LOGICAL_PATHNAMES
    if (logpathnamep(pathname)) {
      value1 = TheLogpathname(pathname)->pathname_name;
    } else
    #endif
    {
      var object erg = ThePathname(pathname)->pathname_name;
      value1 = (eq(STACK_0,S(Kcommon)) ? common_case(erg) : erg);
    }
    mv_count=1; # name als Wert
    skipSTACK(2);
  }

LISPFUN(pathnametype,1,0,norest,key,1, (kw(case)))
# (PATHNAME-TYPE pathname [:case]), CLTL S. 417, CLtL2 S. 644
  {
    var object pathname = coerce_xpathname(STACK_1);
    #ifdef LOGICAL_PATHNAMES
    if (logpathnamep(pathname)) {
      value1 = TheLogpathname(pathname)->pathname_type;
    } else
    #endif
    {
      var object erg = ThePathname(pathname)->pathname_type;
      value1 = (eq(STACK_0,S(Kcommon)) ? common_case(erg) : erg);
    }
    mv_count=1; # type als Wert
    skipSTACK(2);
  }

LISPFUNN(pathnameversion,1)
# (PATHNAME-VERSION pathname), CLTL S. 417, CLtL2 S. 644
  {
    var object pathname = coerce_xpathname(popSTACK());
    #ifdef LOGICAL_PATHNAMES
    if (logpathnamep(pathname)) {
      value1 = TheLogpathname(pathname)->pathname_version;
    } else
    #endif
    {
      #if HAS_VERSION
      value1 = ThePathname(pathname)->pathname_version; # version als Wert
      #else
      value1 = NIL; # NIL als Wert
      #endif
    }
    mv_count=1;
  }

# Zugriffsfunktionen ohne Groß-/Klein-Umwandlung:
# xpathname_host(logical,pathname)
# xpathname_device(logical,pathname)
# xpathname_directory(logical,pathname)
# xpathname_name(logical,pathname)
# xpathname_type(logical,pathname)
# xpathname_version(logical,pathname)
# > pathname: Pathname oder Logical Pathname
# > logical: Flag, ob es sich um einen Logical Pathname handelt
# < ergebnis: Wert der entsprechenden Komponente von pathname
  #ifdef LOGICAL_PATHNAMES
    #if HAS_HOST
      #define xpathname_host(logical,pathname)  \
        (logical ? TheLogpathname(pathname)->pathname_host : ThePathname(pathname)->pathname_host)
    #else
      #define xpathname_host(logical,pathname)  \
        (logical ? TheLogpathname(pathname)->pathname_host : NIL)
    #endif
    #if HAS_DEVICE
      #define xpathname_device(logical,pathname)  \
        (logical ? NIL : ThePathname(pathname)->pathname_device)
    #else
      #define xpathname_device(logical,pathname)  NIL
    #endif
    #define xpathname_directory(logical,pathname)  \
      (logical ? TheLogpathname(pathname)->pathname_directory : ThePathname(pathname)->pathname_directory)
    #define xpathname_name(logical,pathname)  \
      (logical ? TheLogpathname(pathname)->pathname_name : ThePathname(pathname)->pathname_name)
    #define xpathname_type(logical,pathname)  \
      (logical ? TheLogpathname(pathname)->pathname_type : ThePathname(pathname)->pathname_type)
    #if HAS_VERSION
      #define xpathname_version(logical,pathname)  \
        (logical ? TheLogpathname(pathname)->pathname_version : ThePathname(pathname)->pathname_version)
    #else
      #define xpathname_version(logical,pathname)  \
        (logical ? TheLogpathname(pathname)->pathname_version : NIL)
    #endif
  #else
    # logical immer =false
    #if HAS_HOST
      #define xpathname_host(logical,pathname)  ThePathname(pathname)->pathname_host
    #else
      #define xpathname_host(logical,pathname)  NIL
    #endif
    #if HAS_DEVICE
      #define xpathname_device(logical,pathname)  ThePathname(pathname)->pathname_device
    #else
      #define xpathname_device(logical,pathname)  NIL
    #endif
    #define xpathname_directory(logical,pathname)  ThePathname(pathname)->pathname_directory
    #define xpathname_name(logical,pathname)  ThePathname(pathname)->pathname_name
    #define xpathname_type(logical,pathname)  ThePathname(pathname)->pathname_type
    #if HAS_VERSION
      #define xpathname_version(logical,pathname)  ThePathname(pathname)->pathname_version
    #else
      #define xpathname_version(logical,pathname)  NIL
    #endif
  #endif

#ifdef LOGICAL_PATHNAMES

LISPFUNN(logical_pathname,1)
# (LOGICAL-PATHNAME thing), CLtL2 S. 631
  {
    var object thing = popSTACK();
    if (logpathnamep(thing)) {
      # Bei Logical Pathnames ist nichts zu tun.
      value1 = thing; mv_count=1;
    } elif (pathnamep(thing)) {
      # Normale Pathnames können nicht in Logical Pathnames umgewandelt werden.
      pushSTACK(thing); # Wert für Slot DATUM von TYPE-ERROR
      pushSTACK(O(type_logical_pathname)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
      pushSTACK(thing);
      pushSTACK(S(logical_pathname));
      fehler(type_error,
             GETTEXT("~: argument ~ is not a logical pathname, string, stream or symbol")
            );
    } else {
      # sonst: PARSE-NAMESTRING aufrufen:
      pushSTACK(subr_self); # subr_self retten (für spätere Fehlermeldungen)
      # Das Ergebnis von (PARSE-NAMESTRING thing nil empty-logical-pathname)
      # ist garantiert ein logischer Pathname.
      pushSTACK(thing); pushSTACK(NIL); pushSTACK(O(empty_logical_pathname));
      funcall(L(parse_namestring),3);
      subr_self = popSTACK();
      mv_count=1;
    }
  }

LISPFUN(translate_logical_pathname,1,0,norest,key,0,_EMA_)
# (TRANSLATE-LOGICAL-PATHNAME pathname &key), CLtL2 S. 631
  {
    var object pathname;
    # It is not clear from the ANSI CL spec how the argument shall be coerced
    # to a pathname. But the examples in the spec indicate that if the
    # argument is a string, it should be converted to a logical pathname,
    # by calling LOGICAL-PATHNAME, not by calling PATHNAME.
    if (stringp(STACK_0)) {
      funcall(L(logical_pathname),1); pathname = value1;
    } else {
      pathname = coerce_xpathname(popSTACK());
    }
    if (logpathnamep(pathname)) {
      # Umwandeln eines logischen in einen normalen Pathname:
      # (let ((ht (make-hash-table :test #'equal)))
      #   (loop
      #     (when (gethash pathname ht) (error "Translation loop"))
      #     (setf (gethash pathname ht) t)
      #     (let ((host (or (pathname-host pathname) "SYS")))
      #       (unless (logical-host-p host) (error "No translation for host"))
      #       (let* ((translations (gethash host sys::*logical-pathname-translations*))
      #              (translation (assoc pathname translations :test #'pathname-match-p)))
      #         (unless (and translation (consp translation) (consp (cdr translation)))
      #           (error "No translation for pathname")
      #         )
      #         (setq pathname (translate-pathname pathname (first translation) (second translation)))
      #     ) )
      #     (unless (sys::logical-pathname-p pathname) (return))
      #   )
      #   pathname
      # )
      pushSTACK(pathname);
      pushSTACK(S(Ktest)); pushSTACK(L(equal)); funcall(L(make_hash_table),2);
      pushSTACK(value1);
      # Stackaufbau: pathname, ht.
      loop {
        if (!nullp(shifthash(STACK_0,STACK_1,T))) {
          # STACK_1 = pathname; # Wert für Slot PATHNAME von FILE-ERROR
          STACK_0 = STACK_1;
          pushSTACK(S(translate_logical_pathname));
          fehler(file_error,
                 GETTEXT("~: endless loop while resolving ~")
                );
        }
        if (nullp(TheLogpathname(STACK_1)->pathname_host)) {
          # Host NIL durch Default-Host ersetzen:
          var object newp = allocate_logpathname();
          var object oldp = STACK_1;
          TheLogpathname(newp)->pathname_host      = O(default_logical_pathname_host); # Default "SYS"
          TheLogpathname(newp)->pathname_directory = TheLogpathname(oldp)->pathname_directory;
          TheLogpathname(newp)->pathname_name      = TheLogpathname(oldp)->pathname_name;
          TheLogpathname(newp)->pathname_type      = TheLogpathname(oldp)->pathname_type;
          TheLogpathname(newp)->pathname_version   = TheLogpathname(oldp)->pathname_version;
          STACK_1 = newp;
        }
        var object host = TheLogpathname(STACK_1)->pathname_host;
        var object translations = gethash(host,Symbol_value(S(logpathname_translations)));
        if (eq(translations,nullobj)) {
          # STACK_1 = pathname; # Wert für Slot PATHNAME von FILE-ERROR
          STACK_0 = STACK_1;
          pushSTACK(host);
          pushSTACK(S(translate_logical_pathname));
          fehler(file_error,
                 GETTEXT("~: unknown logical host ~ in ~")
                );
        }
        # (ASSOC pathname translations :test #'pathname-match-p):
        pushSTACK(STACK_1); pushSTACK(translations);
        pushSTACK(S(Ktest)); pushSTACK(L(pathname_match_p));
        funcall(L(assoc),4);
        if (atomp(value1) || matomp(Cdr(value1))) {
          # STACK_1 = pathname; # Wert für Slot PATHNAME von FILE-ERROR
          STACK_0 = STACK_1;
          pushSTACK(S(translate_logical_pathname));
          fehler(file_error,
                 GETTEXT("~: No replacement rule for ~ is known.")
                );
        }
        # (TRANSLATE-PATHNAME pathname (first rule) (second rule) :MERGE NIL):
        pushSTACK(STACK_1); pushSTACK(Car(value1)); pushSTACK(Car(Cdr(value1)));
        pushSTACK(S(Kmerge)); pushSTACK(NIL);
        funcall(L(translate_pathname),5);
        STACK_1 = pathname = value1;
        if (!logpathnamep(pathname))
          break;
      }
      skipSTACK(2);
    }
    value1 = pathname; mv_count=1;
  }

# UP: Wandelt ein Objekt in einen nicht-Logical Pathname um.
# coerce_pathname(object)
# > object: Objekt
# < ergebnis: (TRANSLATE-LOGICAL-PATHNAME (PATHNAME Objekt))
# can trigger GC
  local object coerce_pathname (object obj);
  local object coerce_pathname(obj)
    var object obj;
    {
      obj = coerce_xpathname(obj);
      if (pathnamep(obj)) {
        # Bei Pathnames ist nichts zu tun.
        return obj;
      } elif (logpathnamep(obj)) {
        # TRANSLATE-LOGICAL-PATHNAME aufrufen:
        pushSTACK(subr_self); # subr_self retten (für spätere Fehlermeldungen)
        pushSTACK(obj); funcall(L(translate_logical_pathname),1);
        subr_self = popSTACK();
        return value1;
      } else {
        NOTREACHED
      }
    }

#endif

# UP: Legt Teilstrings für STRING_CONCAT auf den STACK, die zusammen den
# String für ein Subdirectory (car path) ergeben.
# subdir_namestring_parts(path)
# > path: ein Cons
# < ergebnis: Anzahl der auf den Stack gelegten Strings
# verändert STACK
  local uintC subdir_namestring_parts (object path);
  local uintC subdir_namestring_parts(path)
    var object path;
    {
      var object subdir = Car(path);
      #ifdef PATHNAME_AMIGAOS
      if (eq(subdir,S(Kparent))) { # :PARENT ?
        return 0; # Leerstring
      } elif (eq(subdir,S(Kwild_inferiors))) { # :WILD-INFERIORS ?
        pushSTACK(O(wildwild_string)); return 1;
      } else {
        # normales subdir
        pushSTACK(subdir); return 1;
      }
      #endif
      #if defined(PATHNAME_UNIX) || defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
      if (eq(subdir,S(Kwild_inferiors))) { # :WILD-INFERIORS ?
        pushSTACK(O(wildwild_string)); return 1;
      } else {
        # normales subdir
        pushSTACK(subdir); return 1;
      }
      #endif
      #ifdef PATHNAME_RISCOS
      if (eq(subdir,S(Kparent))) { # :PARENT ?
        pushSTACK(O(parent_string)); return 1;
      } else {
        # normales subdir
        pushSTACK(subdir); return 1;
      }
      #endif
    }

# UP: Legt Teilstrings für STRING_CONCAT auf den STACK, die zusammen den
# String für den Host des Pathname pathname ergeben.
# host_namestring_parts(pathname)
# > pathname: nicht-Logical Pathname
# < ergebnis: Anzahl der auf den Stack gelegten Strings
# verändert STACK
#if HAS_HOST
  local uintC host_namestring_parts (object pathname);
  local uintC host_namestring_parts(pathname)
    var object pathname;
    {
      var object host = ThePathname(pathname)->pathname_host;
      if (nullp(host)) {
        return 0; # kein String
      } else {
        #ifdef PATHNAME_WIN32
        pushSTACK(O(backslashbackslash_string));
        pushSTACK(host);
        return 2;
        #else
        pushSTACK(host);
        pushSTACK(O(doppelpunkt_string)); # ":"
        return 2;
        #endif
      }
    }
#else
  #define host_namestring_parts(pathname)  (unused (pathname), 0)  # keine Strings
#endif

# UP: Legt Teilstrings für STRING_CONCAT auf den STACK, die zusammen den
# String fürs Device und Directory des Pathname pathname ergeben.
# directory_namestring_parts(pathname)
# > pathname: nicht-Logical Pathname
# < ergebnis: Anzahl der auf den Stack gelegten Strings
# verändert STACK
  local uintC directory_namestring_parts (object pathname);
  local uintC directory_namestring_parts (pathname)
    var object pathname;
    {
      var uintC stringcount = 0; # bisherige Stringzahl = 0
      #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
      # Device:
      {
        var object device = ThePathname(pathname)->pathname_device;
        if (!(nullp(device))) { # NIL -> kein String
          if (eq(device,S(Kwild)))
            device = O(wild_string); # :WILD -> String "*"
          pushSTACK(device); # Device auf den Stack
          stringcount++; # und mitzählen
        }
      }
      #endif
      #ifdef PATHNAME_AMIGAOS
      # Device:
      {
        var object device = ThePathname(pathname)->pathname_device;
        if (!(nullp(device))) { # NIL -> kein String
          pushSTACK(device); # Device auf den Stack
          stringcount += 1; # und mitzählen
          # Wegen :ABSOLUTE kommt gleich danach ein ":" auf den Stack.
        }
      }
      #endif
      #ifdef PATHNAME_RISCOS
      # Device:
      {
        var object device = ThePathname(pathname)->pathname_device;
        if (!(nullp(device))) { # NIL -> kein String
          pushSTACK(O(doppelpunkt_string)); # ":"
          pushSTACK(device); # Device auf den Stack
          pushSTACK(O(punkt_string)); # "."
          stringcount += 3; # und mitzählen
        }
      }
      #endif
      # Directory:
      {
        var object directory = ThePathname(pathname)->pathname_directory;
        #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
        # evtl. Doppelpunkt:
        if (!(stringcount == 0)) { # nur falls schon was auf dem Stack
          pushSTACK(O(doppelpunkt_string)); stringcount++; # ":" auf den Stack
        }
        #endif
        # Ist das erste subdir = :ABSOLUTE oder = :RELATIVE ?
        if (eq(Car(directory),S(Kabsolute))) {
          #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
          pushSTACK(O(backslash_string)); stringcount++; # "\\" auf den Stack
          #endif
          #ifdef PATHNAME_AMIGAOS
          pushSTACK(O(doppelpunkt_string)); stringcount++; # ":" auf den Stack
          #endif
          #ifdef PATHNAME_UNIX
          pushSTACK(O(slash_string)); stringcount++; # "/" auf den Stack
          #endif
          #ifdef PATHNAME_RISCOS
          directory = Cdr(directory); # übergehen
          var object firstdir = Car(directory);
          if (eq(firstdir,S(Kroot))) {
            pushSTACK(O(root_string)); stringcount++; # "$." auf den Stack
          } elif (eq(firstdir,S(Khome))) {
            pushSTACK(O(home_string)); stringcount++; # "&." auf den Stack
          } elif (eq(firstdir,S(Kcurrent))) {
            pushSTACK(O(current_string)); stringcount++; # "@." auf den Stack
          } elif (eq(firstdir,S(Klibrary))) {
            pushSTACK(O(library_string)); stringcount++; # "%." auf den Stack
          } elif (eq(firstdir,S(Kprevious))) {
            pushSTACK(O(previous_string)); stringcount++; # "\\." auf den Stack
          } else {
            NOTREACHED
          }
          #endif
        }
        directory = Cdr(directory); # übergehen
        # weitere subdirs auf den Stack:
        while (consp(directory)) {
          stringcount += subdir_namestring_parts(directory);
          #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
          pushSTACK(O(backslash_string)); stringcount++; # "\\" auf den Stack
          #endif
          #if defined(PATHNAME_UNIX) || defined(PATHNAME_AMIGAOS)
          pushSTACK(O(slash_string)); stringcount++; # "/" auf den Stack
          #endif
          #ifdef PATHNAME_RISCOS
          pushSTACK(O(punkt_string)); stringcount++; # "." auf den Stack
          #endif
          directory = Cdr(directory);
        }
      }
      return stringcount;
    }

# UP: Legt Teilstrings für STRING_CONCAT auf den STACK, die zusammen den
# String für Name und Typ des Pathname ergeben.
# nametype_namestring_parts(name,type,version)
# > name, type, evtl. version: Komponenten des Pathname
# < ergebnis: Anzahl der auf den Stack gelegten Strings
# can trigger GC
# verändert STACK
  #if HAS_VERSION
  local uintC nametype_namestring_parts (object name, object type, object version);
  local uintC nametype_namestring_parts (
    var object name,
    var object type,
    var object version)
  #else
  local uintC nametype_namestring_parts_ (object name, object type);
  local uintC nametype_namestring_parts_ (
    var object name,
    var object type)
  #define nametype_namestring_parts(n,t,v)  nametype_namestring_parts_(n,t)
  #endif
    {
      var uintC stringcount = 0;
      # Name:
      if (!nullp(name)) { # name=NIL -> nicht ausgeben
        pushSTACK(name); # Name auf den Stack
        stringcount++; # und mitzählen
      }
      # Typ:
      if (!nullp(type)) { # type=NIL -> nicht ausgeben
        pushSTACK(O(punkt_string)); # "." auf den Stack
        stringcount++; # und mitzählen
        pushSTACK(type); # Typ auf den Stack
        stringcount++; # und mitzählen
      }
      #if HAS_VERSION
      if (!nullp(version)) { # version=NIL -> nicht ausgeben
        pushSTACK(O(strichpunkt_string)); # ";" auf den Stack
        stringcount++; # und mitzählen
        if (eq(version,S(Knewest)))
          pushSTACK(O(zero_string)); # :NEWEST -> String "0"
        else
          # Version (Integer >0) in String umwandeln: (sys::decimal-string version)
          pushSTACK(decimal_string(version));
        stringcount++; # und mitzählen
      }
      #endif
      return stringcount;
    }

# UP: Legt Teilstrings für STRING_CONCAT auf den STACK, die zusammen den
# String für Name und Typ des Pathname ergeben.
# file_namestring_parts(pathname)
# > pathname: nicht-Logical Pathname
# < ergebnis: Anzahl der auf den Stack gelegten Strings
# can trigger GC
# verändert STACK
  local uintC file_namestring_parts (object pathname);
  local uintC file_namestring_parts(pathname)
    var object pathname;
    {
      return nametype_namestring_parts(ThePathname(pathname)->pathname_name,
                                       ThePathname(pathname)->pathname_type,
                                       ThePathname(pathname)->pathname_version);
    }

# UP: Wandelt Pathname in String um.
# whole_namestring(pathname)
# > pathname: nicht-Logical Pathname
# < ergebnis: Normal-Simple-String
# can trigger GC
  local object whole_namestring (object pathname);
  local object whole_namestring(pathname)
    var object pathname;
    {
      var uintC stringcount;
      stringcount = host_namestring_parts(pathname); # Strings für den Host
      stringcount += directory_namestring_parts(pathname); # Strings fürs Directory
      stringcount += file_namestring_parts(pathname); # Strings für den Filename
      return string_concat(stringcount); # zusammenhängen
    }

# UP: Liefert den String zum Directory eines Pathname.
# directory_namestring(pathname)
# > pathname: nicht-Logical Pathname
# > subr_self: Aufrufer (ein SUBR)
# < ergebnis: Normal-Simple-String
# can trigger GC
  local object directory_namestring (object pathname);
  local object directory_namestring(pathname)
    var object pathname;
    {
      # The function DIRECTORY-NAMESTRING is totally underspecified. It could return
      # a. just the string for the directory portion,
      # b. the string for the device + directory portions,
      # c. the string for the host + device + directory portions.
      # Before we used hosts, we have traditionally returned (b). Now, with hosts,
      # we return (c). This makes most sense, given that CLHS says that programs
      # shouldn't attempt to concatenate the resulting string with anything.
      var uintC stringcount = host_namestring_parts(pathname); # Strings für den Host
      stringcount += directory_namestring_parts(pathname); # Strings fürs Directory
      return string_concat(stringcount); # zusammenhängen
    }

# UP: Returns the string identifying a file in its directory.
# file_namestring(pathname)
# > pathname: non-logical pathname
# > subr_self: caller (a SUBR)
# < result: normal-simple-string
# can trigger GC
  local inline object file_namestring (object pathname);
  local inline object file_namestring(pathname)
    var object pathname;
    {
      var uintC stringcount = file_namestring_parts(pathname); # Strings für den Filename
      return string_concat(stringcount); # zusammenhängen
    }

LISPFUNN(file_namestring,1)
# (FILE-NAMESTRING pathname), CLTL S. 417
  {
    var object pathname = coerce_pathname(popSTACK());
    value1 = file_namestring(pathname); mv_count=1; # zusammenhängen
  }

LISPFUNN(directory_namestring,1)
# (DIRECTORY-NAMESTRING pathname), CLTL S. 417
  {
    var object pathname = coerce_pathname(popSTACK());
    value1 = directory_namestring(pathname); mv_count=1;
  }

LISPFUNN(host_namestring,1)
# (HOST-NAMESTRING pathname), CLTL S. 417
  {
    var object pathname = coerce_pathname(popSTACK());
    #if HAS_HOST
    var uintC stringcount = host_namestring_parts(pathname); # Strings für den Host
    value1 = string_concat(stringcount); # zusammenhängen
    #else
    value1 = O(leer_string); # "" als Wert
    #endif
    mv_count=1;
  }

#if HAS_VERSION || defined(LOGICAL_PATHNAMES)
# UP: Überprüft ein optionales VERSION-Argument.
# test_optional_version(def);
# > STACK_0: VERSION-Argument
# > def: Defaultwert dafür
# > subr_self: Aufrufer (ein SUBR)
# < ergebnis: gültige Version-Komponente
  local object test_optional_version (object def);
  local object test_optional_version(def)
    var object def;
    {
      var object version = STACK_0;
      if (eq(version,unbound)) {
        return def; # nicht angegeben -> Default
      } elif (nullp(version)) {
        # NIL ist OK
      } elif (eq(version,S(Kwild))) {
        # :WILD ist OK
      } elif (eq(version,S(Knewest))) {
        # :NEWEST ist OK
      } elif (posfixnump(version) && !eq(version,Fixnum_0)) {
        # Fixnum >0 ist OK
      } elif (pathnamep(version)) { # Pathname -> dessen Version
        STACK_0 = xpathname_version(false,version);
      }
      #ifdef LOGICAL_PATHNAMES
      elif (logpathnamep(version)) { # Logical Pathname -> dessen Version
        STACK_0 = TheLogpathname(version)->pathname_version;
      }
      #endif
      else { # Keiner der gewünschten Fälle -> Fehler:
        pushSTACK(version); # Wert für Slot DATUM von TYPE-ERROR
        pushSTACK(O(type_version)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
        pushSTACK(version);
        pushSTACK(TheSubr(subr_self)->name);
        fehler(type_error,
               GETTEXT("~: :VERSION-argument should be NIL or a positive fixnum or :WILD or :NEWEST, not ~")
              );
      }
      return version;
    }
#else
# UP: Überprüft ein optionales VERSION-Argument.
# test_optional_version();
# > STACK_0: VERSION-Argument
# > subr_self: Aufrufer (ein SUBR)
  #define test_optional_version(def)  test_optional_version_()
  local void test_optional_version_ (void);
  local void test_optional_version_()
    {
      var object version = STACK_0;
      if (eq(version,unbound) # nicht angegeben?
          || nullp(version)         # oder NIL ?
          || eq(version,S(Kwild))   # oder :WILD ?
          || eq(version,S(Knewest)) # oder :NEWEST ?
         )
        return; # ja -> OK
      else {
        pushSTACK(version); # Wert für Slot DATUM von TYPE-ERROR
        pushSTACK(O(type_version)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
        pushSTACK(version);
        pushSTACK(TheSubr(subr_self)->name);
        fehler(type_error,
               GETTEXT("~: :VERSION-argument should be NIL or :WILD or :NEWEST, not ~")
              );
      }
    }
#endif

#if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)

# Das Betriebssystem verwaltet ein Default-Drive.
# Das Betriebssystem verwaltet auf jedem Drive ein Default-Directory. Dieses
# kann sich allerdings ändern, wenn eine andere Diskette eingelegt wird.

# Es wird ein Default-Drive geführt: DEFAULT_DRIVE = O(default_drive).

# Die Variable *DEFAULT-PATHNAME-DEFAULTS* enthält (als Pathname) den
# Defaultwert für jede MERGE-Operation. Dies ist derjenige, den das System
# in vom Benutzer eingegebene Pathnames "hineininterpretiert".
# Er wird auf dem neuesten Stand des DEFAULT_DRIVE gehalten: bei der
# Initialisierung das aktuelle Device (im Sinne von DOS), bei der
# Änderung von DEFAULT_DRIVE mittels CD.

#endif # PATHNAME_OS2 || PATHNAME_WIN32

#if defined(PATHNAME_UNIX) || defined(PATHNAME_AMIGAOS)

# Die Variable *DEFAULT-PATHNAME-DEFAULTS* enthält (als Pathname) den
# Defaultwert für jede MERGE-Operation. Dies ist derjenige, den das System
# in vom Benutzer eingegebene Pathnames "hineininterpretiert".

#endif

#ifdef UNIX

# Das Betriebssystem verwaltet ein Default-Directory ("working directory")
# für diesen Prozess. Es kann mit chdir verändert und mit getwd abgefragt
# werden. Siehe CHDIR(2) und GETWD(3).

#endif

#ifdef AMIGAOS

# Das Betriebssystem verwaltet ein Default-Directory ("current directory")
# für diesen Prozess. Es kann mit CurrentDir verändert und mit einer
# Kombination aus Examine und ParentDir abgefragt werden.

#endif

# UP: Neuberechnung von *DEFAULT-PATHNAME-DEFAULTS*
#if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
# aus DEFAULT_DRIVE
#endif
# recalc_defaults_pathname();
# < ergebnis: Wert von *DEFAULT-PATHNAME-DEFAULTS*, ein Pathname
# can trigger GC
  local object recalc_defaults_pathname (void);
  local object recalc_defaults_pathname()
    {
      #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
      # (MAKE-PATHNAME :DEVICE default-drive) ausführen:
      pushSTACK(S(Kdevice)); pushSTACK(O(default_drive));
      funcall(L(make_pathname),2);
      #endif
      #if defined(PATHNAME_UNIX) || defined(PATHNAME_AMIGAOS) || defined(PATHNAME_RISCOS)
      # (MAKE-PATHNAME) ausführen:
      funcall(L(make_pathname),0);
      #endif
      # und *DEFAULT-PATHNAME-DEFAULTS* zuweisen:
      return Symbol_value(S(default_pathname_defaults)) = value1;
    }

# UP: Liefert den Default-Pathname.
# defaults_pathname()
# < ergebnis: Wert von *DEFAULT-PATHNAME-DEFAULTS*, ein Pathname
# can trigger GC
  local object defaults_pathname (void);
  local object defaults_pathname()
    {
      var object pathname = Symbol_value(S(default_pathname_defaults)); # Wert von *DEFAULT-PATHNAME-DEFAULTS*
      if (pathnamep(pathname)) {
        # ist Pathname -> OK
        return pathname;
      } else {
        # sonst Warnung:
        pushSTACK(subr_self); # subr_self retten (für spätere Fehlermeldungen)
        # (WARN "Der Wert von ~S war kein Pathname. ~:*~S wird zurückgesetzt." ...)
        pushSTACK(OLS(defaults_warn_string));
        pushSTACK(S(default_pathname_defaults));
        funcall(S(warn),2);
        # und neuberechnen:
        pathname = recalc_defaults_pathname();
        subr_self = popSTACK();
        return pathname;
      }
    }

LISPFUN(merge_pathnames,1,2,norest,key,1, (kw(wild)))
# (MERGE-PATHNAMES pathname [defaults [default-version]] [:wild]), CLTL S. 415
# Definition assuming that HAS_HOST and HAS_DEVICE are exclusive:
# (defun merge-pathnames (pathname &optional (defaults *default-pathname-defaults*) default-version)
#   (setq pathname (pathname pathname))
#   (setq defaults (pathname defaults))
#   (multiple-value-call #'make-pathname
#if HAS_HOST
#     (if (or (equal (pathname-host pathname) (pathname-host defaults))
#             (null (pathname-host pathname))
#         )
#       (values
#         :host (or (pathname-host pathname) (pathname-host defaults))
#endif
#if HAS_DEVICE
#     (if (or (equal (pathname-device pathname) (pathname-device defaults))
#             (null (pathname-device pathname))
#         )
#       (values
#         :device (or (pathname-device pathname) (pathname-device defaults))
#endif
#         :directory
#           (let ((pathname-dir (pathname-directory pathname))
#                 (defaults-dir (pathname-directory defaults)))
#             (if (eq (car pathname-dir) ':RELATIVE)
#               (cond ((null (cdr pathname-dir)) defaults-dir)
#                     ((or *merge-pathnames-ansi*
#                          (not (eq (car defaults-dir) ':RELATIVE)) ; <----
#                      )
#                      (append defaults-dir (cdr pathname-dir))
#                     )
#                     (t pathname-dir)
#               )
#               pathname-dir
#           ) )
#       )
#       (values
#if HAS_HOST
#         :host (pathname-host pathname)
#endif
#if HAS_DEVICE
#         :device (pathname-device pathname)
#endif
#         :directory (pathname-directory pathname)
#     ) )
#     :name (or (pathname-name pathname) (pathname-name defaults))
#     :type (or (pathname-type pathname) (pathname-type defaults))
# ) )
#
# If HAS_HOST and HAS_DEVICE are both true, the semantics are more
# complicated; see CLHS for details.
#
# If the :WILD argument is specified, :WILD components are replaced,
# instead of missing components.
#
# Explanation of the "<----" line:
#
# Roger Kehr <kehr@iti.informatik.th-darmstadt.de> asks why in CLISP
#
# (merge-pathnames (make-pathname :directory '(:relative "x"))
#                  (make-pathname :directory '(:relative "y")))
# => #"x/"
#
# where he expects to get #"y/x/".
#
# There are two reasons for this behaviour:
#
# 1. An informal one: I found the latter behaviour confusing and changed
#    CLISP to do it the former way. It seems to work better this way.
#
# 2. A formal one: MERGE-PATHNAMES is used to specify default components
#    for pathnames, so there is some analogy between (MERGE-PATHNAMES a b)
#    and (or a b). Obviously putting in the same default a second time
#    should do the same as putting it in once:
#
#      (or a b b) is the same as (or a b), so
#
#      (MERGE-PATHNAMES (MERGE-PATHNAMES a b) b) should be the same as
#      (MERGE-PATHNAMES a b).
#
#    (This question actually matters because in Common Lisp there is
#    no distinction between "pathnames with defaults merged-in" and
#    "pathnames with defaults not yet applied". For example, you don't
#    know whether COMPILE-FILE will merge in some defaults.)
#
#    Now, (MERGE-PATHNAMES (MERGE-PATHNAMES '#"x/" '#"y/") '#"y/")
#    and  (MERGE-PATHNAMES '#"x/" '#"y/")
#    are equal in CLISP's implementation, but not in implementations
#    that strictly follow the Common Lisp spec. In fact, the above
#    twice-default = once-default rule holds for all pathnames in CLISP.
#
  {
    # :wild #'make-pathname causes NIL components to be considered specified,
    # only #<unbound> components are considered unspecified.
    var bool called_from_make_pathname = eq(STACK_0,L(make_pathname));
    # :wild t causes only wild components to be considered unspecified.
    var bool wildp = !(eq(STACK_0,unbound) || nullp(STACK_0));
    skipSTACK(1);
    # default-version überprüfen:
    #if HAS_VERSION || defined(LOGICAL_PATHNAMES)
    {
      var object v = test_optional_version(S(Knewest)); # Default ist :NEWEST
      STACK_0 = STACK_1; STACK_1 = STACK_2; STACK_2 = v;
    }
    # Stackaufbau: default-version, pathname, defaults.
    #else
    test_optional_version(S(Knewest)); skipSTACK(1);
    # Stackaufbau: pathname, defaults.
    #endif
    # pathname und defaults überprüfen:
    # defaults zu einem Pathname machen:
    STACK_0 = test_default_pathname(STACK_0);
    # pathname zu einem Pathname machen:
    #ifdef LOGICAL_PATHNAMES
    if (logpathnamep(STACK_0)) {
      if (!xpathnamep(STACK_1)) {
        pushSTACK(subr_self); # subr_self retten (für spätere Fehlermeldungen)
        # Das Ergebnis von (PARSE-NAMESTRING obj nil empty-logical-pathname)
        # ist garantiert ein logischer Pathname.
        pushSTACK(STACK_(1+1)); pushSTACK(NIL); pushSTACK(O(empty_logical_pathname));
        funcall(L(parse_namestring),3);
        subr_self = popSTACK();
        STACK_1 = value1;
      }
    } else
    #endif
      STACK_1 = coerce_xpathname(STACK_1);
    #ifdef LOGICAL_PATHNAMES
    if (logpathnamep(STACK_1) && logpathnamep(STACK_0)) {
      # MERGE-PATHNAMES für Logical Pathnames
      var object newp = allocate_logpathname(); # neuen Pathname holen
      var object d = popSTACK(); # defaults
      var object p = popSTACK(); # pathname
      # Hosts matchen:
      {
        var object p_host = TheLogpathname(p)->pathname_host;
        var object d_host = TheLogpathname(d)->pathname_host;
        TheLogpathname(newp)->pathname_host = p_host; # erstmal new-host := pathname-host
        if (equal(p_host,d_host))
          goto lmatch_directories;
        if (wildp ? false : nullp(p_host)) {
          # pathname-host nicht angegeben, aber defaults-host angegeben:
          TheLogpathname(newp)->pathname_host = d_host; # new-host := defaults-host
          goto lmatch_directories;
        }
      }
      # Directories nicht matchen:
      {
        # new-directory := pathname-directory :
        TheLogpathname(newp)->pathname_directory = TheLogpathname(p)->pathname_directory;
      }
      goto ldirectories_OK;
     lmatch_directories:
      # Directories matchen:
      {
        var object p_directory = TheLogpathname(p)->pathname_directory; # pathname-directory
        var object d_directory = TheLogpathname(d)->pathname_directory; # defaults-directory
        var object new_subdirs = p_directory;
        if (called_from_make_pathname) {
          # pathname-subdirs nicht angegeben?
          if (eq(p_directory,unbound))
            # ja -> verwende defaults-subdirs:
            new_subdirs = d_directory;
        } else {
          # Fängt pathname-subdirs mit :RELATIVE an?
          if (!wildp && eq(Car(p_directory),S(Krelative))) {
            # ja.
            # Endet pathname-subdirs danach?
            if (matomp(Cdr(p_directory))) {
              # ja -> verwende defaults-subdirs:
              new_subdirs = d_directory;
            } else {
              # nein.
              # Fängt defaults-subdirs mit :RELATIVE an?
              if (eq(Car(d_directory),S(Krelative))) {
                # ja -> Ersetzen von :RELATIVE in pathname-subdirs
                # durch das gesamte defaults-subdirs ist nicht sinnvoll
                # (da nicht klar ist, auf was das dabei entstehende
                # Default-Directory sich beziehen soll). Daher nichts tun:
              } else {
                # nein -> Um :RELATIVE aufzulösen: ersetze :RELATIVE
                # in pathname-subdirs durch defaults-subdirs, d.h.
                # bilde (append defaults-subdirs (cdr pathname-subdirs)) =
                # (nreconc (reverse defaults-subdirs) (cdr pathname-subdirs)) :
                pushSTACK(p); pushSTACK(d); pushSTACK(newp);
                pushSTACK(Cdr(p_directory));
                {
                  var object temp = reverse(d_directory);
                  new_subdirs = nreconc(temp,popSTACK());
                }
                newp = popSTACK(); d = popSTACK(); p = popSTACK();
              }
            }
          }
        }
        TheLogpathname(newp)->pathname_directory = new_subdirs; # new-directory := new-subdirs
      }
     ldirectories_OK:
      # Nun sind die Directories OK.
      # Name matchen:
      # Verwende pathname-name, falls angegeben, und defaults-name sonst.
      {
        var object p_name = TheLogpathname(p)->pathname_name;
        TheLogpathname(newp)->pathname_name =
          (!(called_from_make_pathname ? eq(p_name,unbound) : wildp ? eq(p_name,S(Kwild)) : nullp(p_name))
           ? p_name
           : TheLogpathname(d)->pathname_name
          );
      }
      # Typ matchen:
      # Verwende pathname-type, falls angegeben, und defaults-type sonst.
      {
        var object p_type = TheLogpathname(p)->pathname_type;
        TheLogpathname(newp)->pathname_type =
          (!(called_from_make_pathname ? eq(p_type,unbound) : wildp ? eq(p_type,S(Kwild)) : nullp(p_type))
           ? p_type
           : TheLogpathname(d)->pathname_type
          );
      }
      # Version matchen:
      # Verwende pathname-version, falls angegeben, und default-version sonst.
      {
        var object p_version = TheLogpathname(p)->pathname_version;
        TheLogpathname(newp)->pathname_version =
          (!(called_from_make_pathname ? eq(p_version,unbound) : wildp ? eq(p_version,S(Kwild)) : nullp(p_version))
           ? p_version
           : STACK_0
          );
        skipSTACK(1);
      }
      # new als Wert:
      value1 = newp; mv_count=1;
      return;
    }
    # nicht beides logische Pathnames -> erst in normale Pathnames umwandeln:
    STACK_1 = coerce_pathname(STACK_1);
    STACK_0 = coerce_pathname(STACK_0);
    #endif
    var object newp = allocate_pathname(); # neuen Pathname holen
    var object d = popSTACK(); # defaults
    var object p = popSTACK(); # pathname
    #if HAS_HOST
    # Hosts matchen:
    {
      var object p_host = ThePathname(p)->pathname_host;
      var object d_host = ThePathname(d)->pathname_host;
      ThePathname(newp)->pathname_host = p_host; # erstmal new-host := pathname-host
      # beide Hosts gleich -> Devices matchen:
      if (equal(p_host,d_host))
        goto match_devices;
      if (!(wildp ? false : nullp(p_host)))
        goto notmatch_devices;
      #ifdef PATHNAME_WIN32
      var object p_device = ThePathname(p)->pathname_device;
      # On Win32, a non-null p_device implicitly designates p_host as the
      # local machine. It must not be overridden by d_host.
      if (!(called_from_make_pathname ? eq(p_device,unbound) :
            wildp ? eq(p_device,S(Kwild)) : nullp(p_device)
         ) )
        goto notmatch_devices;
      #endif
      # pathname-host nicht angegeben, aber defaults-host angegeben:
      ThePathname(newp)->pathname_host = d_host; # new-host := defaults-host
      goto match_devices;
    }
    #endif
   match_devices:
    #if HAS_DEVICE
    # Devices matchen:
    {
      var object p_device = ThePathname(p)->pathname_device;
      var object d_device = ThePathname(d)->pathname_device;
      ThePathname(newp)->pathname_device = p_device; # erstmal new-device := pathname-device
      # beide Devices gleich -> Directories matchen:
      if (equal(p_device,d_device))
        goto match_directories;
      if (called_from_make_pathname ? eq(p_device,unbound) :
          wildp ? eq(p_device,S(Kwild)) : nullp(p_device)
         ) {
        # pathname-device nicht angegeben, aber defaults-device angegeben:
        ThePathname(newp)->pathname_device = d_device; # new-device := defaults-device
        goto match_directories;
      }
      goto notmatch_directories;
    }
    #endif
    # Directories matchen:
   match_directories:
    {
      var object p_directory = ThePathname(p)->pathname_directory; # pathname-directory
      var object d_directory = ThePathname(d)->pathname_directory; # defaults-directory
      var object new_subdirs = p_directory;
      if (called_from_make_pathname) {
        # pathname-subdirs nicht angegeben?
        if (eq(p_directory,unbound))
          # ja -> verwende defaults-subdirs:
          new_subdirs = d_directory;
      } else {
        # Fängt pathname-subdirs mit :RELATIVE an?
        if (!wildp && eq(Car(p_directory),S(Krelative))) {
          # ja.
          # Endet pathname-subdirs danach?
          if (matomp(Cdr(p_directory))) {
            # ja -> verwende defaults-subdirs:
            new_subdirs = d_directory;
          } else {
            # nein.
            # Fängt defaults-subdirs mit :RELATIVE an?
            if (nullp(Symbol_value(S(merge_pathnames_ansi)))
                && eq(Car(d_directory),S(Krelative))) {
              # ja -> Ersetzen von :RELATIVE in pathname-subdirs
              # durch das gesamte defaults-subdirs ist nicht sinnvoll
              # (da nicht klar ist, auf was das dabei entstehende
              # Default-Directory sich beziehen soll). Daher nichts tun:
            } else {
              # nein -> Um :RELATIVE aufzulösen: ersetze :RELATIVE
              # in pathname-subdirs durch defaults-subdirs, d.h.
              # bilde (append defaults-subdirs (cdr pathname-subdirs)) =
              # (nreconc (reverse defaults-subdirs) (cdr pathname-subdirs)) :
              pushSTACK(p); pushSTACK(d); pushSTACK(newp);
              pushSTACK(Cdr(p_directory));
              {
                var object temp = reverse(d_directory);
                new_subdirs = nreconc(temp,popSTACK());
              }
              newp = popSTACK(); d = popSTACK(); p = popSTACK();
            }
          }
        }
      }
      ThePathname(newp)->pathname_directory = new_subdirs; # new-directory := new-subdirs
    }
    goto directories_OK;
    # Devices nicht matchen:
   notmatch_devices:
    #if HAS_DEVICE
    {
      # new-device := pathname-device :
      ThePathname(newp)->pathname_device = ThePathname(p)->pathname_device;
    }
    #endif
    # Directories nicht matchen:
   notmatch_directories:
    {
      # new-directory := pathname-directory :
      ThePathname(newp)->pathname_directory = ThePathname(p)->pathname_directory;
    }
   directories_OK:
    # Nun sind die Directories OK.
    # Name matchen:
    # Verwende pathname-name, falls angegeben, und defaults-name sonst.
    {
      var object p_name = ThePathname(p)->pathname_name;
      ThePathname(newp)->pathname_name =
        (!(called_from_make_pathname ? eq(p_name,unbound) : wildp ? equal(p_name,O(wild_string)) : nullp(p_name))
         ? p_name
         : ThePathname(d)->pathname_name
        );
    }
    # Typ matchen:
    # Verwende pathname-type, falls angegeben, und defaults-type sonst.
    {
      var object p_type = ThePathname(p)->pathname_type;
      ThePathname(newp)->pathname_type =
        (!(called_from_make_pathname ? eq(p_type,unbound) : wildp ? equal(p_type,O(wild_string)) : nullp(p_type))
         ? p_type
         : ThePathname(d)->pathname_type
        );
    }
    #if HAS_VERSION
    # Version matchen:
    # Verwende pathname-version, falls angegeben, und default-version sonst.
    {
      var object p_version = ThePathname(p)->pathname_version;
      ThePathname(newp)->pathname_version =
        (!(called_from_make_pathname ? eq(p_version,unbound) : wildp ? eq(p_version,S(Kwild)) : nullp(p_version))
         ? p_version
         : STACK_0
        );
    }
    #endif
    #if HAS_VERSION || defined(LOGICAL_PATHNAMES)
    skipSTACK(1);
    #endif
    # new als Wert:
    value1 = newp; mv_count=1;
  }

LISPFUN(enough_namestring,1,1,norest,nokey,0,NIL)
# (ENOUGH-NAMESTRING pathname [defaults]), CLTL S. 417
# Definition assuming that HAS_HOST and HAS_DEVICE are exclusive:
# (defun enough-namestring (pathname &optional (defaults *default-pathname-defaults*))
#   (setq pathname (pathname pathname))
#   (setq defaults (pathname defaults))
#   (namestring
#     (multiple-value-call #'make-pathname
#if HAS_HOST
#       (if (equal (pathname-host pathname) (pathname-host defaults))
#         (values
#           :host nil
#endif
#if HAS_DEVICE
#       (if (equal (pathname-device pathname) (pathname-device defaults))
#         (values
#           :device nil
#endif
#           :directory
#             (let ((pathname-dir (pathname-directory pathname))
#                   (defaults-dir (pathname-directory defaults)))
#               (if (equal pathname-dir defaults-dir)
#                 (list ':RELATIVE)
#                 (if (and (not (eq (car pathname-dir) ':RELATIVE))
#                          (not (eq (car defaults-dir) ':RELATIVE))
#                          (equal (subseq pathname-dir 0 (min (length pathname-dir) (length defaults-dir)))
#                                 defaults-dir
#                     )    )
#                   (cons ':RELATIVE (nthcdr (length defaults-dir) pathname-dir))
#                   pathname-dir
#             ) ) )
#         )
#         (values
#if HAS_HOST
#           :host (pathname-host pathname)
#endif
#if HAS_DEVICE
#           :device (pathname-device pathname)
#endif
#           :directory (pathname-directory pathname)
#       ) )
#       :name (if (equal (pathname-name pathname) (pathname-name defaults))
#               nil
#               (pathname-name pathname)
#             )
#       :type (if (equal (pathname-type pathname) (pathname-type defaults))
#               nil
#               (pathname-type pathname)
#             )
# ) ) )
#
# If HAS_HOST and HAS_DEVICE are both true, the semantics are more
# complicated; see CLHS for details.
  {
    # pathname und defaults überprüfen:
    # pathname zu einem Pathname machen:
    STACK_1 = coerce_pathname(STACK_1);
    # defaults zu einem Pathname machen:
    STACK_0 = coerce_pathname(test_default_pathname(STACK_0));
    # neuen Pathname holen:
    var object newp = allocate_pathname();
    pushSTACK(newp);
    # Stackaufbau: pathname, defaults, new.
    #if HAS_HOST
    # Hosts vergleichen:
    {
      var object p_host = ThePathname(STACK_2)->pathname_host; # pathname-host
      var object d_host = ThePathname(STACK_1)->pathname_host; # defaults-host
      if (equal(p_host,d_host)) { # beide Hosts gleich ?
        # ja.
        ThePathname(newp)->pathname_host = NIL; # new-host := NIL
    #endif
    #if HAS_DEVICE
    # Devices vergleichen:
    {
      var object p_device = ThePathname(STACK_2)->pathname_device; # pathname-device
      var object d_device = ThePathname(STACK_1)->pathname_device; # defaults-device
      if (equal(p_device,d_device)) { # beide Devices gleich ?
        # ja.
        ThePathname(newp)->pathname_device = NIL; # new-device := NIL
    #endif
        {
          var object p_directory = ThePathname(STACK_2)->pathname_directory; # pathname-directory
          var object d_directory = ThePathname(STACK_1)->pathname_directory; # defaults-directory
          var object new_subdirs;
          # vergleiche pathname-subdirs und defaults-subdirs:
          if (equal(p_directory,d_directory)) {
            # gleich -> verwende (cons :RELATIVE nil) :
            new_subdirs = NIL; goto insert_RELATIVE;
          } else {
            # Fängt weder pathname-subdirs noch defaults-subdirs
            # mit :RELATIVE an?
            if (   (!eq(Car(p_directory),S(Krelative)))
                && (!eq(Car(d_directory),S(Krelative)))
               ) {
              # ja -> testen, ob defaults-subdirs ein Anfangsstück
              # der Liste pathname-subdirs ist:
              var object Lp = p_directory;
              var object Ld = d_directory;
              # Ist Ld ein Anfangsstück von Lp ?
              loop {
                if (atomp(Ld)) { # Ld zu Ende -> ja
                  new_subdirs = Lp; goto insert_RELATIVE;
                }
                if (atomp(Lp))
                  break; # Lp zu Ende -> nein
                if (!equal(Car(Ld),Car(Lp))) # verschiedene Listenelemente?
                  break; # -> nein
                Ld = Cdr(Ld); Lp = Cdr(Lp); # Listen weiterrücken
              }
            }
            new_subdirs = p_directory; # new-subdirs := pathname-subdirs
            goto subdirs_ok;
          }
         insert_RELATIVE:
          # new-subdirs := (cons :RELATIVE new-subdirs) :
          {
            pushSTACK(new_subdirs);
            new_subdirs = allocate_cons();
            Cdr(new_subdirs) = popSTACK(); Car(new_subdirs) = S(Krelative);
          }
         subdirs_ok: # new-subdirs ist die neue Subdir-Liste.
          # new-directory := new-subdirs :
          ThePathname(newp=STACK_0)->pathname_directory = new_subdirs;
        }
    #if HAS_DEVICE
      } else {
        # verschiedene Devices
        # (Note for PATHNAME_WIN32: If we have different devices, the common
        # host must have been NIL.)
        # new-device := pathname-device :
        ThePathname(newp)->pathname_device = p_device;
        # new-directory := pathname-directory :
        ThePathname(newp)->pathname_directory = ThePathname(STACK_2)->pathname_directory;
      }
    }
    #endif
    #if HAS_HOST
      } else {
        # verschiedene Hosts
        # new-host := pathname-host :
        ThePathname(newp)->pathname_host = p_host;
        #if HAS_DEVICE
        # new-device := pathname-device :
        ThePathname(newp)->pathname_device = ThePathname(STACK_2)->pathname_device;
        #endif
        # new-directory := pathname-directory :
        ThePathname(newp)->pathname_directory = ThePathname(STACK_2)->pathname_directory;
      }
    }
    #endif
    # name einfüllen:
    {
      var object p_name = ThePathname(STACK_2)->pathname_name; # pathname-name
      var object d_name = ThePathname(STACK_1)->pathname_name; # defaults-name
      ThePathname(newp)->pathname_name = (equal(p_name,d_name) ? NIL : p_name);
    }
    # type einfüllen:
    {
      var object p_type = ThePathname(STACK_2)->pathname_type; # pathname-type
      var object d_type = ThePathname(STACK_1)->pathname_type; # defaults-type
      ThePathname(newp)->pathname_type = (equal(p_type,d_type) ? NIL : p_type);
    }
    skipSTACK(3);
    # (namestring new) bilden:
    subr_self = L(namestring); # ("aktuelles" SUBR für Fehlermeldung)
    value1 = whole_namestring(newp); mv_count=1;
  }

#ifdef LOGICAL_PATHNAMES

# UP: Überprüft, ob object ein zulässiger Name ist:
# :WILD oder ein Simple-String aus gültigen Zeichen, keine adjazenten '*'.
# legal_logical_word(object)
# > object: if a simple-string, a normal-simple-string
  local bool legal_logical_word (object obj);
  local bool legal_logical_word(obj)
    var object obj;
    {
      if (eq(obj,S(Kwild)))
        return true;
      if (!simple_string_p(obj))
        return false;
      ASSERT(sstring_normal_p(obj));
      var uintL len = Sstring_length(obj);
      if (len==0)
        return false; # leeres Word ist verboten
      var const chart* charptr = &TheSstring(obj)->data[0];
      var bool last_was_star = false;
      dotimespL(len,len, {
        var chart ch = *charptr++;
        if (!(legal_logical_word_char(ch) || chareq(ch,ascii('*'))))
          return false;
        if (chareq(ch,ascii('*'))) {
          if (last_was_star)
            return false; # adjazente '*' sind verboten
          last_was_star = true;
        } else {
          last_was_star = false;
        }
      });
      return true;
    }

#endif

#if defined(PATHNAME_NOEXT) || defined(PATHNAME_RISCOS)

# UP: Überprüft, ob object ein zulässiger Name ist:
# ein Simple-String aus gültigen Zeichen
# legal_name(object)
# > object: if a simple-string, a normal-simple-string
  local bool legal_name (object obj);
  local bool legal_name(obj)
    var object obj;
    {
      if (!simple_string_p(obj))
        return false;
      ASSERT(sstring_normal_p(obj));
      var uintL len = Sstring_length(obj);
      if (len > 0) {
        var const chart* charptr = &TheSstring(obj)->data[0];
        dotimespL(len,len, { if (!legal_namechar(*charptr++)) { return false; } } );
      }
      return true;
    }

# UP: Überprüft, ob object ein zulässiger Name ist:
# ein Simple-String aus gültigen Zeichen, ohne '.'
# legal_type(object)
# > object: if a simple-string, a normal-simple-string
  local bool legal_type (object obj);
#ifdef PATHNAME_NOEXT
  local bool legal_type(obj)
    var object obj;
    {
      if (!simple_string_p(obj))
        return false;
      ASSERT(sstring_normal_p(obj));
      var uintL len = Sstring_length(obj);
      if (len > 0) {
        var const chart* charptr = &TheSstring(obj)->data[0];
        dotimespL(len,len, {
          var chart ch = *charptr++;
          if (chareq(ch,ascii('.')) || !legal_namechar(ch))
            return false;
        });
      }
      return true;
    }
#endif
#ifdef PATHNAME_RISCOS
  #define legal_type(obj)  legal_name(obj)
#endif

#endif # PATHNAME_NOEXT || PATHNAME_RISCOS

LISPFUN(make_pathname,0,0,norest,key,8,\
        (kw(defaults),kw(case),kw(host),kw(device),kw(directory),kw(name),kw(type),kw(version)) )
# (MAKE-PATHNAME [:host] [:device] [:directory] [:name] [:type] [:version]
#                [:defaults] [:case]),
# CLTL S. 416, CLtL2 S. 643
  # Stackaufbau: defaults, case, host, device, directory, name, type, version.
  {
    var bool logical = false;
    var bool convert = eq(STACK_6,S(Kcommon));
    # 1. host überprüfen:
    #ifdef LOGICAL_PATHNAMES
    # Damit TRANSLATE-PATHNAMES logische Pathnames erzeugen kann:
    if (logpathnamep(STACK_5)) {
      STACK_5 = TheLogpathname(STACK_5)->pathname_host;
      logical = true; convert = false;
    }
    #endif
    #if HAS_HOST
    STACK_5 = test_optional_host(STACK_5,convert);
    #else
    STACK_5 = test_optional_host(STACK_5);
    #endif
    #ifdef LOGICAL_PATHNAMES
    if (!nullp(STACK_5) && logical_host_p(STACK_5)) {
      logical = true; convert = false; STACK_5 = string_upcase(STACK_5);
    }
    #endif
    # 2. device überprüfen:
    #if HAS_DEVICE
    {
      var object device = STACK_4;
      if (eq(device,unbound)) { # angegeben ?
        # nein
        if (eq(STACK_7,unbound)) # keine Defaults ?
          STACK_4 = NIL; # -> verwende NIL
      } else {
        if (stringp(device))
          STACK_4 = device = coerce_normal_ss(device);
        if (convert)
          STACK_4 = device = common_case(device);
        if (nullp(device)) # = NIL ?
          goto device_ok;
        #ifdef LOGICAL_PATHNAMES
        elif (logical) {
          if (logpathnamep(device)) { # Pathname -> dessen Device
            STACK_4 = NIL; goto device_ok;
          }
        }
        #endif
        #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
        elif (eq(device,S(Kwild))) # = :WILD ?
          goto device_ok;
        elif (simple_string_p(device)) { # Simple-String ?
          if (Sstring_length(device) == 1) { # der Länge 1 ?
            var chart ch = TheSstring(device)->data[0];
            if ((as_cint(ch) >= 'A') && (as_cint(ch) <= 'Z')) # mit Buchstaben >='A' und <='Z' ?
              goto device_ok;
          }
        }
        #endif
        #ifdef PATHNAME_AMIGAOS
        elif (simple_string_p(device)) { # Simple-String ?
          var uintL count = Sstring_length(device);
          if (count > 0) {
            var const chart* ptr = &TheSstring(device)->data[0];
            dotimespL(count,count, {
              if (!legal_namechar(*ptr++)) goto device_not_ok;
            });
          }
          goto device_ok;
         device_not_ok: ;
        }
        #endif
        #ifdef PATHNAME_RISCOS
        elif (simple_string_p(device)) { # Simple-String ?
          var uintL count = Sstring_length(device);
          if (count > 0) {
            var const chart* ptr = &TheSstring(device)->data[0];
            dotimespL(count,count, {
              var chart ch = *ptr++;
              if (!(legal_namechar(ch) && !chareq(ch,ascii('*')) && !singlewild_char_p(ch)))
                goto device_not_ok;
            });
          }
          goto device_ok;
         device_not_ok: ;
        }
        #endif
        elif (xpathnamep(device)) { # Pathname -> dessen Device
          #ifdef LOGICAL_PATHNAMES
          device = coerce_pathname(device);
          #endif
          STACK_4 = ThePathname(device)->pathname_device; goto device_ok;
        }
        # Keiner der gewünschten Fälle -> Fehler:
        pushSTACK(STACK_4); pushSTACK(S(Kdevice)); goto fehler_arg;
       device_ok: ;
        #ifdef PATHNAME_WIN32
        if (!nullp(STACK_5) && !nullp(STACK_4)) {
          pushSTACK(STACK_4);
          pushSTACK(STACK_(5+1));
          pushSTACK(TheSubr(subr_self)->name);
          fehler(error,
                 GETTEXT("~: on host ~, device ~ is invalid, should be NIL")
                );
        }
        #endif
      }
    }
    #else
    {
      var object device = STACK_4;
      if (!eq(device,unbound)) # angegeben ?
        if (!(nullp(device) || xpathnamep(device))) { # NIL oder Pathname -> OK
          # Keiner der gewünschten Fälle -> Fehler:
          pushSTACK(STACK_4); pushSTACK(S(Kdevice)); goto fehler_arg;
        }
    }
    #endif
    # 3. directory überprüfen:
    {
      var object directory = STACK_3;
      if (eq(directory,unbound) && !eq(STACK_7,unbound)) { # nicht angegeben
        # aber Defaults
        goto directory_ok;
      } elif (eq(directory,unbound) || nullp(directory)) { # nicht angegeben oder =NIL ?
        #ifdef PATHNAME_AMIGAOS
        if (!nullp(STACK_4)) # Device angegeben (bei nicht-logical Pathname)?
          STACK_3 = O(directory_absolute); # Default ist (:ABSOLUTE)
        else
        #endif
          STACK_3 = O(directory_default); # Default ist (:RELATIVE)
        goto directory_ok;
      } elif (consp(directory)) { # ein Cons?
        STACK_3 = directory = subst_coerce_normal_ss(directory);
        if (convert)
          STACK_3 = directory = subst_common_case(directory);
        # Der CAR entweder :RELATIVE oder :ABSOLUTE ?
        if (!consp(directory))
          goto directory_bad;
        {
          var object startpoint = Car(directory);
          if (!(eq(startpoint,S(Krelative)) || eq(startpoint,S(Kabsolute))))
            goto directory_bad;
          #ifdef PATHNAME_RISCOS
          if (!logical && eq(startpoint,S(Kabsolute))) {
            directory = Cdr(directory);
            startpoint = Car(directory);
            if (!(eq(startpoint,S(Kroot))
                  || eq(startpoint,S(Khome))
                  || eq(startpoint,S(Kcurrent))
                  || eq(startpoint,S(Klibrary))
                  || eq(startpoint,S(Kprevious))
               ) )
              goto directory_bad;
          }
          #endif
        }
        directory = Cdr(directory);
        # Subdir-Liste überprüfen:
        while (consp(directory)) {
          # nächstes subdir überprüfen:
          var object subdir = Car(directory);
          #ifdef LOGICAL_PATHNAMES
          if (logical) {
            if (!(eq(subdir,S(Kwild_inferiors)) || legal_logical_word(subdir)))
              goto directory_bad;
          } else
          #endif
          {
            #ifdef PATHNAME_NOEXT
            #ifdef PATHNAME_AMIGAOS
            if (!(eq(subdir,S(Kwild_inferiors)) || eq(subdir,S(Kparent))
                  || legal_name(subdir)
               ) )
              goto directory_bad;
            #endif
            #if defined(PATHNAME_UNIX) || defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
            if (!(eq(subdir,S(Kwild_inferiors)) || legal_name(subdir)))
              goto directory_bad;
            #endif
            #endif
            #ifdef PATHNAME_RISCOS
            if (!(eq(subdir,S(Kparent)) || legal_name(subdir)))
              goto directory_bad;
            #endif
          }
          directory = Cdr(directory);
        }
        goto directory_ok;
      }
      #ifdef LOGICAL_PATHNAMES
      elif (logical) {
        if (logpathnamep(directory)) { # Pathname -> dessen Directory
          STACK_3 = TheLogpathname(directory)->pathname_directory; goto directory_ok;
        }
      }
      #endif
      elif (xpathnamep(directory)) { # Pathname -> dessen Directory
        #ifdef LOGICAL_PATHNAMES
        directory = coerce_pathname(directory);
        #endif
        STACK_3 = ThePathname(directory)->pathname_directory;
        goto directory_ok;
      }
      # Keiner der gewünschten Fälle -> Fehler:
     directory_bad:
      pushSTACK(STACK_3); pushSTACK(S(Kdirectory)); goto fehler_arg;
     directory_ok: ;
      #ifdef PATHNAME_AMIGAOS
      # Bei device /= NIL muss directory mit :ABSOLUTE anfangen:
      if (!nullp(STACK_4) && !eq(Car(STACK_3),S(Kabsolute)))
        goto directory_bad;
      #endif
    }
    # 4. name überprüfen:
    {
      var object name = STACK_2;
      if (stringp(name))
        STACK_2 = name = subst_coerce_normal_ss(name);
      if (convert)
        STACK_2 = name = common_case(name);
      if (eq(name,unbound)) {
        # nicht angegeben
        if (eq(STACK_7,unbound)) # keine Defaults ?
          STACK_2 = NIL; # -> verwende NIL
      } elif (nullp(name)) { # NIL ist OK
      }
      #ifdef LOGICAL_PATHNAMES
      elif (logical) {
        if (legal_logical_word(name)) { # OK
        } elif (logpathnamep(name)) { # Pathname -> dessen Name
          STACK_2 = TheLogpathname(name)->pathname_name;
        } else { # Keiner der gewünschten Fälle -> Fehler:
          pushSTACK(STACK_2); pushSTACK(S(Kname)); goto fehler_arg;
        }
      }
      #endif
      #if defined(PATHNAME_NOEXT) || defined(PATHNAME_RISCOS)
      elif (eq(name,S(Kwild))) {
        STACK_2 = O(wild_string); # aus :WILD mache "*"
      }
      #endif
      elif (equal(name,O(leer_string))) { # name = "" ?
        STACK_2 = NIL; # ja -> verwende NIL
      } elif (legal_name(name)) { # zulässiger Name ist OK
      } elif (xpathnamep(name)) { # Pathname -> dessen Name
        #ifdef LOGICAL_PATHNAMES
        name = coerce_pathname(name);
        #endif
        STACK_2 = ThePathname(name)->pathname_name;
      } else { # Keiner der gewünschten Fälle -> Fehler:
        pushSTACK(STACK_2); pushSTACK(S(Kname)); goto fehler_arg;
      }
    }
    # 5. type überprüfen:
    {
      var object type = STACK_1;
      if (stringp(type))
        STACK_1 = type = subst_coerce_normal_ss(type);
      if (convert)
        STACK_1 = type = common_case(type);
      if (eq(type,unbound)) {
        # nicht angegeben
        if (eq(STACK_7,unbound)) # keine Defaults ?
          STACK_1 = NIL; # -> verwende NIL
      } elif (nullp(type)) { # NIL ist OK
      }
      #ifdef LOGICAL_PATHNAMES
      elif (logical) {
        if (legal_logical_word(type)) { # OK
        } elif (logpathnamep(type)) { # Pathname -> dessen Typ
          STACK_1 = TheLogpathname(type)->pathname_type;
        } else { # Keiner der gewünschten Fälle -> Fehler:
          pushSTACK(STACK_1); pushSTACK(S(Ktype)); goto fehler_arg;
        }
      }
      #endif
      #if defined(PATHNAME_NOEXT) || defined(PATHNAME_RISCOS)
      elif (eq(type,S(Kwild))) {
        STACK_1 = O(wild_string); # aus :WILD mache "*"
      }
      #endif
      elif (legal_type(type)) { # zulässiger Typ ist OK
      } elif (xpathnamep(type)) { # Pathname -> dessen Typ
        #ifdef LOGICAL_PATHNAMES
        type = coerce_pathname(type);
        #endif
        STACK_1 = ThePathname(type)->pathname_type;
      } else { # Keiner der gewünschten Fälle -> Fehler:
        pushSTACK(STACK_1); pushSTACK(S(Ktype)); goto fehler_arg;
      }
    }
    # 6. version überprüfen:
    #if HAS_VERSION || defined(LOGICAL_PATHNAMES)
    STACK_0 = test_optional_version(eq(STACK_7,unbound) ? NIL : unbound); # Default ist NIL
    #else
    test_optional_version(NIL);
    #endif
    # 7. Pathname bauen:
    {
      var object pathname;
      #ifdef LOGICAL_PATHNAMES
      if (logical) {
        pathname = allocate_logpathname(); # neuer Logical Pathname
        TheLogpathname(pathname)->pathname_version   = popSTACK();
        TheLogpathname(pathname)->pathname_type      = popSTACK();
        TheLogpathname(pathname)->pathname_name      = popSTACK();
        TheLogpathname(pathname)->pathname_directory = popSTACK();
        skipSTACK(1);
        TheLogpathname(pathname)->pathname_host      = popSTACK();
      } else
      #endif
      {
        pathname = allocate_pathname(); # neuer Pathname
        #if HAS_VERSION
        ThePathname(pathname)->pathname_version   = popSTACK();
        #else
        skipSTACK(1);
        #endif
        ThePathname(pathname)->pathname_type      = popSTACK();
        ThePathname(pathname)->pathname_name      = popSTACK();
        ThePathname(pathname)->pathname_directory = popSTACK();
        #if HAS_DEVICE
        ThePathname(pathname)->pathname_device    = popSTACK();
        #else
        skipSTACK(1);
        #endif
        #if HAS_HOST
        ThePathname(pathname)->pathname_host      = popSTACK();
        #else
        skipSTACK(1);
        #endif
      }
      skipSTACK(1); # case vergessen
      # 8. evtl. Defaults hineinmergen:
      var object defaults = popSTACK();
      if (eq(defaults,unbound)) {
        # keine Defaults angegeben -> pathname als Wert
        value1 = pathname;
      } else {
        # (MERGE-PATHNAMES pathname defaults [nil] :wild #'make-pathname) aufrufen:
        pushSTACK(pathname); pushSTACK(defaults); pushSTACK(NIL);
        pushSTACK(S(Kwild)); pushSTACK(L(make_pathname));
        funcall(L(merge_pathnames),5);
      }
      mv_count=1;
      return;
    }
    # Fehlermeldung:
   fehler_arg:
    pushSTACK(TheSubr(subr_self)->name);
    fehler(error,
           GETTEXT("~: illegal ~ argument ~")
          );
  }

#ifdef LOGICAL_PATHNAMES

LISPFUN(make_logical_pathname,0,0,norest,key,8,\
        (kw(defaults),kw(case),kw(host),kw(device),kw(directory),kw(name),kw(type),kw(version)) )
# (MAKE-LOGICAL-PATHNAME [:host] [:device] [:directory] [:name] [:type] [:version]
#                        [:defaults] [:case]),
# wie MAKE-PATHNAME, nur dass ein Logical Pathname gebildet wird.
  {
    # Ein logischer Pathname als :HOST-Argument zu MAKE-PATHNAME
    # erzwingt einen logischen Pathname als Ergebnis.
    var object obj = allocate_logpathname();
    TheLogpathname(obj)->pathname_host = (!eq(STACK_5,unbound) ? STACK_5 : NIL);
    STACK_5 = obj;
    # weiter bei MAKE-PATHNAME.
    C_make_pathname();
  }

#endif

#ifdef USER_HOMEDIR
LISPFUN(user_homedir_pathname,0,1,norest,nokey,0,NIL)
# (USER-HOMEDIR-PATHNAME [host]), CLTL S. 418
  {
    #if HAS_HOST
    STACK_0 = test_optional_host(STACK_0,false); # Host überprüfen
    if (!nullp(STACK_0)) {
      #if defined(PATHNAME_RISCOS)
      {
        var object pathname = allocate_pathname(); # neuer Pathname
        ThePathname(pathname)->pathname_host      = popSTACK();
        #if HAS_DEVICE
        ThePathname(pathname)->pathname_device    = NIL;
        #endif
        ThePathname(pathname)->pathname_directory = O(directory_homedir);
        ThePathname(pathname)->pathname_name      = NIL;
        ThePathname(pathname)->pathname_type      = NIL;
        #if HAS_VERSION
        ThePathname(pathname)->pathname_version   = NIL;
        #endif
        value1 = pathname;
      }
      #elif defined(PATHNAME_WIN32)
      # This is very primitive. Does Windows have the notion of homedirs on
      # remote hosts??
      {
        var object pathname = allocate_pathname(); # neuer Pathname
        ThePathname(pathname)->pathname_host      = popSTACK();
        #if HAS_DEVICE
        ThePathname(pathname)->pathname_device    = NIL;
        #endif
        ThePathname(pathname)->pathname_directory = O(directory_absolute);
        ThePathname(pathname)->pathname_name      = NIL;
        ThePathname(pathname)->pathname_type      = NIL;
        #if HAS_VERSION
        ThePathname(pathname)->pathname_version   = NIL;
        #endif
        value1 = pathname;
      }
      #else
      ??
      #endif
    } else {
      # no host given
      skipSTACK(1);
      value1 = O(user_homedir); # User-Homedir-Pathname
    }
    #else
    test_optional_host(popSTACK()); # Host überprüfen und ignorieren
    value1 = O(user_homedir); # User-Homedir-Pathname
    #endif
    mv_count=1; # als Wert
  }
#endif

# UP: Kopiert einen Pathname.
# copy_pathname(pathname)
# > pathname: nicht-Logical Pathname
# < ergebnis: Kopie des Pathname, mit denselben Komponenten
# can trigger GC
  local object copy_pathname (object pathname);
  local object copy_pathname(pathname)
    var object pathname;
    {
      pushSTACK(pathname);
      var object newp = allocate_pathname();
      pathname = popSTACK();
      #if HAS_HOST
      ThePathname(newp)->pathname_host      = ThePathname(pathname)->pathname_host     ;
      #endif
      #if HAS_DEVICE
      ThePathname(newp)->pathname_device    = ThePathname(pathname)->pathname_device   ;
      #endif
      ThePathname(newp)->pathname_directory = ThePathname(pathname)->pathname_directory;
      ThePathname(newp)->pathname_name      = ThePathname(pathname)->pathname_name     ;
      ThePathname(newp)->pathname_type      = ThePathname(pathname)->pathname_type     ;
      #if HAS_VERSION
      ThePathname(newp)->pathname_version   = ThePathname(pathname)->pathname_version  ;
      #endif
      return newp;
    }

# Wildcards
# =========

#if defined(PATHNAME_NOEXT) || defined(PATHNAME_RISCOS)
# UP: Testet, ob ein Simple-String Wildcards enthält.
# has_wildcards(string)
# > string: Normal-Simple-String
# < ergebnis: true wenn string Wildcard-Zeichen enthält
  local bool has_wildcards (object string);
  local bool has_wildcards(string)
    var object string;
    {
      var uintL len = Sstring_length(string);
      if (len > 0) {
        var const chart* charptr = &TheSstring(string)->data[0];
        dotimespL(len,len, {
          var chart ch = *charptr++;
          if (chareq(ch,ascii('*')) # Wildcard für beliebig viele Zeichen
              || singlewild_char_p(ch) # Wildcard für genau ein Zeichen
             )
            return true;
        });
      }
      return false;
    }
#endif

#ifdef LOGICAL_PATHNAMES
# UP: Testet, ob ein Simple-String Wildcards enthält.
# has_word_wildcards(string)
# > string: Normal-Simple-String
# < ergebnis: true wenn string Wildcard-Zeichen enthält
  local bool has_word_wildcards (object string);
  local bool has_word_wildcards(string)
    var object string;
    {
      var uintL len = Sstring_length(string);
      if (len > 0) {
        var const chart* charptr = &TheSstring(string)->data[0];
        dotimespL(len,len, {
          if (chareq(*charptr++,ascii('*')))
            return true;
        });
      }
      return false;
    }
#endif

# UP: Testet, ob die Host-Komponente eines Pathname Wildcards enthält.
# has_host_wildcards(pathname)
# > pathname: Pathname
# < ergebnis: true wenn (PATHNAME-HOST pathname) Wildcards enthält.
  local bool has_host_wildcards (object pathname);
  # Host kann keine Wildcards enthalten.
  #define has_host_wildcards(pathname)  (unused (pathname), false)

# UP: Testet, ob die Device-Komponente eines Pathname Wildcards enthält.
# has_device_wildcards(pathname)
# > pathname: Pathname
# < ergebnis: true wenn (PATHNAME-DEVICE pathname) Wildcards enthält.
  local bool has_device_wildcards (object pathname);
  local bool has_device_wildcards(pathname)
    var object pathname;
    {
      #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
      #ifdef LOGICAL_PATHNAMES
      if (logpathnamep(pathname))
        return false;
      #endif
      # Device überprüfen: = :WILD ?
      return eq(ThePathname(pathname)->pathname_device,S(Kwild));
      #else
      return false;
      #endif
    }

# UP: Testet, ob die Directory-Komponente eines Pathname Wildcards enthält.
# has_directory_wildcards(pathname)
# > pathname: Pathname
# < ergebnis: true wenn (PATHNAME-DIRECTORY pathname) Wildcards enthält.
  local bool has_directory_wildcards (object pathname);
  local bool has_directory_wildcards(pathname)
    var object pathname;
    {
      # Directory überprüfen:
      #ifdef LOGICAL_PATHNAMES
      if (logpathnamep(pathname)) {
        var object directory = TheLogpathname(pathname)->pathname_directory;
        while (consp(directory = Cdr(directory))) {
          var object subdir = Car(directory);
          if (simple_string_p(subdir)) {
            if (has_word_wildcards(subdir))
              return true;
          } else {
            if (eq(subdir,S(Kwild)) || eq(subdir,S(Kwild_inferiors)))
              return true;
          }
        }
        return false;
      }
      #endif
      var object directory = ThePathname(pathname)->pathname_directory;
      while (consp(directory = Cdr(directory))) {
        var object subdir = Car(directory);
        #ifdef PATHNAME_NOEXT
        if (simple_string_p(subdir)) {
          if (has_wildcards(subdir))
            return true;
        } else {
          if (eq(subdir,S(Kwild_inferiors)))
            return true;
        }
        #endif
        #ifdef PATHNAME_RISCOS
        if (simple_string_p(subdir)) {
          if (has_wildcards(subdir))
            return true;
        }
        #endif
      }
      return false;
    }

# UP: Testet, ob die Name-Komponente eines Pathname Wildcards enthält.
# has_name_wildcards(pathname)
# > pathname: Pathname
# < ergebnis: true wenn (PATHNAME-NAME pathname) Wildcards enthält.
  local bool has_name_wildcards (object pathname);
  local bool has_name_wildcards(pathname)
    var object pathname;
    {
      # Name überprüfen:
      #ifdef LOGICAL_PATHNAMES
      if (logpathnamep(pathname)) {
        var object name = TheLogpathname(pathname)->pathname_name;
        if (simple_string_p(name)) {
          if (has_word_wildcards(name))
            return true;
        } else {
          if (eq(name,S(Kwild)))
            return true;
        }
        return false;
      }
      #endif
      #if defined(PATHNAME_NOEXT) || defined(PATHNAME_RISCOS)
      {
        var object name = ThePathname(pathname)->pathname_name;
        if (simple_string_p(name)) {
          if (has_wildcards(name))
            return true;
        }
      }
      #endif
      return false;
    }

# UP: Testet, ob die Type-Komponente eines Pathname Wildcards enthält.
# has_type_wildcards(pathname)
# > pathname: Pathname
# < ergebnis: true wenn (PATHNAME-TYPE pathname) Wildcards enthält.
  local bool has_type_wildcards (object pathname);
  local bool has_type_wildcards(pathname)
    var object pathname;
    {
      # Typ überprüfen:
      #ifdef LOGICAL_PATHNAMES
      if (logpathnamep(pathname)) {
        var object type = TheLogpathname(pathname)->pathname_type;
        if (simple_string_p(type)) {
          if (has_word_wildcards(type))
            return true;
        } else {
          if (eq(type,S(Kwild)))
            return true;
        }
        return false;
      }
      #endif
      #if defined(PATHNAME_NOEXT) || defined(PATHNAME_RISCOS)
      {
        var object type = ThePathname(pathname)->pathname_type;
        if (simple_string_p(type)) {
          if (has_wildcards(type))
            return true;
        }
      }
      #endif
      return false;
    }

# UP: Testet, ob die Version-Komponente eines Pathname Wildcards enthält.
# has_version_wildcards(pathname)
# > pathname: Pathname
# < ergebnis: true wenn (PATHNAME-VERSION pathname) Wildcards enthält.
  local bool has_version_wildcards (object pathname);
  local bool has_version_wildcards(pathname)
    var object pathname;
    {
      # Version überprüfen:
      #ifdef LOGICAL_PATHNAMES
      if (logpathnamep(pathname)) {
        if (eq(TheLogpathname(pathname)->pathname_version,S(Kwild)))
          return true;
        return false;
      }
      #endif
      return false;
    }

# UP: Testet, ob irgendeine Komponente eines Pathname Wildcards enthält.
# has_some_wildcards(pathname)
# > pathname: Pathname
# < ergebnis: true wenn pathname Wildcards enthält.
  local bool has_some_wildcards (object pathname);
  local bool has_some_wildcards(pathname)
    var object pathname;
    {
      if (has_host_wildcards(pathname)) return true;
      if (has_device_wildcards(pathname)) return true;
      if (has_directory_wildcards(pathname)) return true;
      if (has_name_wildcards(pathname)) return true;
      if (has_type_wildcards(pathname)) return true;
      if (has_version_wildcards(pathname)) return true;
      return false;
    }

# UP: Überprüft, ob ein Pathname keine Wildcards enthält.
# check_no_wildcards(pathname);
# > pathname: Pathname
  local void check_no_wildcards (object pathname);
  local void check_no_wildcards(pathname)
    var object pathname;
    {
      if (!has_some_wildcards(pathname))
        # Keine Wildcards gefunden.
        return;
      # Fehlermeldung, wenn der Pathname Wildcards enthält:
      pushSTACK(pathname); # Wert für Slot PATHNAME von FILE-ERROR
      pushSTACK(pathname);
      fehler(file_error,
             GETTEXT("wildcards are not allowed here: ~")
            );
    }

LISPFUN(wild_pathname_p,1,1,norest,nokey,0,NIL)
# (WILD-PATHNAME-P pathname [field-key]), CLtL2 S. 623
  {
    var object pathname = coerce_xpathname(STACK_1);
    var object key = STACK_0;
    var bool erg;
    if (eq(key,unbound) || nullp(key)) {
      erg = has_some_wildcards(pathname);
    } elif (eq(key,S(Khost))) {
      erg = has_host_wildcards(pathname);
    } elif (eq(key,S(Kdevice))) {
      erg = has_device_wildcards(pathname);
    } elif (eq(key,S(Kdirectory))) {
      erg = has_directory_wildcards(pathname);
    } elif (eq(key,S(Kname))) {
      erg = has_name_wildcards(pathname);
    } elif (eq(key,S(Ktype))) {
      erg = has_type_wildcards(pathname);
    } elif (eq(key,S(Kversion))) {
      erg = has_version_wildcards(pathname);
    } else {
      pushSTACK(key); # Wert für Slot DATUM von TYPE-ERROR
      pushSTACK(O(type_pathname_field_key)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
      pushSTACK(NIL);
      pushSTACK(S(Kversion));
      pushSTACK(S(Ktype));
      pushSTACK(S(Kname));
      pushSTACK(S(Kdirectory));
      pushSTACK(S(Kdevice));
      pushSTACK(S(Khost));
      pushSTACK(key);
      pushSTACK(TheSubr(subr_self)->name);
      fehler(type_error,
             GETTEXT("~: argument ~ should be ~, ~, ~, ~, ~, ~ or ~")
            );
    }
    value1 = (erg ? T : NIL); mv_count=1; # boolescher Wert
    skipSTACK(2);
  }

# Wildcard Matching
# =================

# For the purposes of wildcard matching, according to CLHS, non-present
# components (i.e. NIL or a directory = (:RELATIVE)) are treated as wild.

#if defined(PATHNAME_NOEXT) || defined(LOGICAL_PATHNAMES)

  # UP: Matcht einen Wildcard-String ("Muster") mit einem "Beispiel".
  # > muster: Normal-Simple-String, mit Platzhaltern
  #           '?' für genau 1 Zeichen
  #           '*' für beliebig viele Zeichen
  # > beispiel: Normal-Simple-String, der damit zu matchen ist
  local bool wildcard_match (object muster, object beispiel);
  # rekursive Implementation wegen Backtracking:
  local bool wildcard_match_ab (uintL m_count, const chart* m_ptr, uintL b_count, const chart* b_ptr);
  local bool wildcard_match(muster,beispiel)
    var object muster;
    var object beispiel;
    {
      ASSERT(sstring_normal_p(muster));
      ASSERT(sstring_normal_p(beispiel));
      return wildcard_match_ab(
                               /* m_count = */ Sstring_length(muster),
                               /* m_ptr   = */ &TheSstring(muster)->data[0],
                               /* b_count = */ Sstring_length(beispiel),
                               /* b_ptr   = */ &TheSstring(beispiel)->data[0]
                              );
    }
  local bool wildcard_match_ab(m_count,m_ptr,b_count,b_ptr)
    var uintL m_count;
    var const chart* m_ptr;
    var uintL b_count;
    var const chart* b_ptr;
    {
      var chart c;
      loop {
        if (m_count==0)
          return (b_count==0 ? true : false); # "" matcht nur ""
        m_count--;
        c = *m_ptr++; # nächstes Match-Zeichen
        if (chareq(c,ascii('?'))) { # Wildcard '?'
          if (b_count==0) return false; # mindestens ein Zeichen muss noch kommen
          b_count--; b_ptr++; # es wird ignoriert
        } elif (chareq(c,ascii('*')))
          break; # Wildcard '*' später
        else { # alles andere muss genau matchen:
          if (b_count==0) return false;
          b_count--; if (!equal_pathchar(*b_ptr++,c)) return false;
        }
      }
      # Wildcard '*': Suche nächstes non-Wildcard-Zeichen und zähle die '?'
      # mit (denn eine Folge '*??*???***?' matcht alles, was mindestens so
      # lang ist, wie die Folge Fragezeichen enthält). Man kann die '?' auch
      # gleich verwerten, denn '*??*???***?' ist zu '??????*' äquivalent.
      loop {
        if (m_count==0) return true; # Wildcard am Ende matcht den Rest.
        m_count--;
        c = *m_ptr++; # nächstes Match-Zeichen
        if (chareq(c,ascii('?'))) { # Fragezeichen: nach vorne ziehen, sofort abarbeiten
          if (b_count==0) return false;
          b_count--; b_ptr++;
        }
        elif (!chareq(c,ascii('*')))
          break;
      }
      # c = nächstes non-Wildcard-Zeichen. Suche es.
      loop {
        if (b_count==0) return false; # c nicht gefunden
        b_count--;
        if (equal_pathchar(*b_ptr++,c)) {
          if (wildcard_match_ab(m_count,m_ptr,b_count,b_ptr))
            return true;
        }
      }
    }

#endif

# UPs: Matcht jeweils eine Pathname-Komponente ("Beispiel") und
# eine Pathname-Komponente ("Muster").
  local bool host_match (object muster, object beispiel, bool logical);
  local bool device_match (object muster, object beispiel, bool logical);
  local bool directory_match (object muster, object beispiel, bool logical);
  local bool nametype_match (object muster, object beispiel, bool logical);
  local bool version_match (object muster, object beispiel, bool logical);
  local bool host_match(muster,beispiel,logical)
    var object muster;
    var object beispiel;
    var bool logical;
    {
      #ifdef LOGICAL_PATHNAMES
      if (logical) {
        if (nullp(muster)) return true;
        return equal(muster,beispiel);
      }
      #endif
      #if HAS_HOST
      if (nullp(muster)) return true;
      return equal(muster,beispiel);
      #else
      return true;
      #endif
    }
  local bool device_match(muster,beispiel,logical)
    var object muster;
    var object beispiel;
    var bool logical;
    {
      #if HAS_DEVICE
      #ifdef LOGICAL_PATHNAMES
      if (logical) {
        return true;
      }
      #endif
      if (nullp(muster)) return true;
      #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
      if (eq(muster,S(Kwild))) return true;
      if (eq(beispiel,S(Kwild))) return false;
      #endif
      #if defined(PATHNAME_AMIGAOS) || defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
      return equalp(muster,beispiel);
      #else
      return equal(muster,beispiel);
      #endif
      #else
      return true;
      #endif
    }
  local bool nametype_match_aux (object muster, object beispiel, bool logical);
  local bool nametype_match_aux(muster,beispiel,logical)
    var object muster;
    var object beispiel;
    var bool logical;
    {
      #ifdef LOGICAL_PATHNAMES
      if (logical) {
        if (eq(muster,S(Kwild))) return true;
        if (eq(beispiel,S(Kwild))) return false;
        if (nullp(muster)) {
          if (nullp(beispiel))
            return true;
          else
            return false;
        }
        if (nullp(beispiel)) {
          return false;
        }
        return wildcard_match(muster,beispiel);
      }
      #endif
      #ifdef PATHNAME_NOEXT
      if (nullp(muster)) {
        if (nullp(beispiel))
          return true;
        else
          return false;
      }
      if (nullp(beispiel)) {
        return false;
      }
      return wildcard_match(muster,beispiel);
      #endif
    }
  local bool subdir_match(muster,beispiel,logical)
    var object muster;
    var object beispiel;
    var bool logical;
    {
      if (eq(muster,beispiel)) return true;
      #ifdef LOGICAL_PATHNAMES
      if (logical) {
        if (eq(muster,S(Kwild))) return true;
        if (!simple_string_p(muster) || !simple_string_p(beispiel)) return false;
        return wildcard_match(muster,beispiel);
      }
      #endif
      #ifdef PATHNAME_NOEXT
      if (!simple_string_p(muster) || !simple_string_p(beispiel)) return false;
      return wildcard_match(muster,beispiel);
      #endif
    }
  # rekursive Implementation wegen Backtracking:
  local bool directory_match_ab (object m_list, object b_list, bool logical);
  local bool directory_match_ab(m_list,b_list,logical)
    var object m_list;
    var object b_list;
    var bool logical;
    {
      # Algorithmus analog zu wildcard_match_ab.
      var object item;
      loop {
        if (atomp(m_list)) { return atomp(b_list); }
        item = Car(m_list); m_list = Cdr(m_list);
        if (eq(item,S(Kwild_inferiors))) break;
        if (atomp(b_list)) return false;
        if (!subdir_match(item,Car(b_list),logical)) return false;
        b_list = Cdr(b_list);
      }
      loop {
        if (atomp(m_list)) return true;
        item = Car(m_list); m_list = Cdr(m_list);
        if (!eq(item,S(Kwild_inferiors))) break;
      }
      loop {
        if (atomp(b_list)) return false;
        if (subdir_match(item,Car(b_list),logical)) {
          b_list = Cdr(b_list);
          if (directory_match_ab(m_list,b_list,logical)) return true;
        } else {
          b_list = Cdr(b_list);
        }
      }
    }
  local bool directory_match(muster,beispiel,logical)
    var object muster;
    var object beispiel;
    var bool logical;
    {
      # muster mit O(directory_default) vergleichen:
      if (eq(Car(muster),S(Krelative)) && nullp(Cdr(muster)))
        return true;
      # Startpoint matchen:
      if (!eq(Car(muster),Car(beispiel)))
        return false;
      muster = Cdr(muster); beispiel = Cdr(beispiel);
      # subdirs matchen:
      return directory_match_ab(muster,beispiel,logical);
    }
  local bool nametype_match(muster,beispiel,logical)
    var object muster;
    var object beispiel;
    var bool logical;
    {
      if (nullp(muster)) return true;
      return nametype_match_aux(muster,beispiel,logical);
    }
  local bool version_match(muster,beispiel,logical)
    var object muster;
    var object beispiel;
    var bool logical;
    {
      #ifdef LOGICAL_PATHNAMES
      if (logical) {
        if (nullp(muster) || eq(muster,S(Kwild))) return true;
        return eql(muster,beispiel);
      }
      #endif
      #if HAS_VERSION
      if (nullp(muster) || eq(muster,S(Kwild))) return true;
      if (eq(beispiel,S(Kwild))) return false;
      if (eql(muster,beispiel)) return true;
      return false;
      #else
      return true;
      #endif
    }

LISPFUNN(pathname_match_p,2)
# (PATHNAME-MATCH-P pathname wildname), CLtL2 S. 623
  {
    # Stackaufbau: pathname, wildname.
    var bool logical = false;
    STACK_1 = coerce_xpathname(STACK_1);
    STACK_0 = coerce_xpathname(STACK_0);
    #ifdef LOGICAL_PATHNAMES
    if (logpathnamep(STACK_1) && logpathnamep(STACK_0)) {
      logical = true;
    } else {
      # nicht beides logische Pathnames -> erst in normale Pathnames umwandeln:
      STACK_1 = coerce_pathname(STACK_1);
      STACK_0 = coerce_pathname(STACK_0);
    }
    #endif
    var object wildname = popSTACK();
    var object pathname = popSTACK();
    if (!host_match(xpathname_host(logical,wildname),
                    xpathname_host(logical,pathname),
                    logical
       )           )
      goto no;
    if (!device_match(xpathname_device(logical,wildname),
                      xpathname_device(logical,pathname),
                      logical
       )             )
      goto no;
    if (!directory_match(xpathname_directory(logical,wildname),
                         xpathname_directory(logical,pathname),
                         logical
       )                )
      goto no;
    if (!nametype_match(xpathname_name(logical,wildname),
                        xpathname_name(logical,pathname),
                        logical
       )               )
      goto no;
    if (!nametype_match(xpathname_type(logical,wildname),
                        xpathname_type(logical,pathname),
                        logical
       )               )
      goto no;
    if (!version_match(xpathname_version(logical,wildname),
                       xpathname_version(logical,pathname),
                       logical
       )              )
      goto no;
   yes:
    value1 = T; mv_count=1; return;
   no:
    value1 = NIL; mv_count=1; return;
  }

# (TRANSLATE-PATHNAME beispiel muster1 muster2) implemented as follows:
# 1. (PATHNAME-MATCH-P beispiel muster1) while checking, extract
#    text items from the substitution pattern (:WILD -> "*").
# 2. Put the text items into muster2 until muster2 is full or all the
#    text items are used up
# 3. finally, (MERGE-PATHNAMES modifiziertes_muster2 beispiel).

  # UP: Compare a wildcard string ("Muster") with "Beispiel".
  # wildcard_diff(muster,beispiel,previous,solutions);
  # > muster: normal simple string, with substitution characters
  #           '?' for exactly 1 character
  #           '*' for as many characters as desired
  # > beispiel: normal simple string, to compare with
  # > previous: the already known result of comparison
  #             (reversed list of normal simple strings, NILs and lists)
  # > solutions: address of a list in the STACK, onto which the results of
  #              the comparisons (reversed list of normal simple strings
  #              and lists) have to be consed
  # can trigger GC

  # Here you need not Lisp or C, but PROLOG!

  # (PUSH previous solutions)
  #define push_solution()  \
    { var object new_cons = allocate_cons(); \
      Car(new_cons) = *previous;             \
      Cdr(new_cons) = *solutions;            \
      *solutions = new_cons;                 \
    }
  # (PUSH (CONS new_piece previous) solutions)
  #define push_solution_with(new_piece)  \
    { pushSTACK(new_piece);                                   \
     {var object new_cons = allocate_cons();                  \
      Car(new_cons) = STACK_0; Cdr(new_cons) = *previous;     \
      STACK_0 = new_cons;                                     \
      new_cons = allocate_cons();                             \
      Car(new_cons) = popSTACK(); Cdr(new_cons) = *solutions; \
      *solutions = new_cons;                                  \
    }}

#if defined(PATHNAME_NOEXT) || defined(LOGICAL_PATHNAMES)

  local void wildcard_diff (object muster, object beispiel, const object* previous, object* solutions);

  # rekursive Implementation wegen Backtracking:
  local void wildcard_diff_ab (object muster, object beispiel, uintL m_index, uintL b_index, const object* previous, object* solutions);

  local void wildcard_diff(muster,beispiel,previous,solutions)
    var object muster;
    var object beispiel;
    var const object* previous;
    var object* solutions;
    {
      ASSERT(sstring_normal_p(muster));
      ASSERT(sstring_normal_p(beispiel));
      wildcard_diff_ab(muster,beispiel,0,0,previous,solutions);
    }

  local void wildcard_diff_ab(muster,beispiel,m_index,b_index,previous,solutions)
    var object muster;
    var object beispiel;
    var uintL m_index;
    var uintL b_index;
    var const object* previous;
    var object* solutions;
    {
      var chart c;
      loop {
        if (m_index == Sstring_length(muster)) {
          if (b_index == Sstring_length(beispiel))
            push_solution();
          return;
        }
        c = TheSstring(muster)->data[m_index++];
        if (chareq(c,ascii('*')))
          break;
        if (b_index == Sstring_length(beispiel))
          return;
        if (chareq(c,ascii('?'))) {
          # recursive call to wildcard_diff_ab(), with extended previous:
          c = TheSstring(beispiel)->data[b_index++];
          pushSTACK(muster); pushSTACK(beispiel);
          {
            var object new_string = allocate_string(1);
            TheSstring(new_string)->data[0] = c;
            pushSTACK(new_string);
          }
          {
            var object new_cons = allocate_cons();
            Car(new_cons) = STACK_0; Cdr(new_cons) = *previous;
            STACK_0 = new_cons; # (CONS ... previous)
          }
          wildcard_diff_ab(STACK_2,STACK_1,m_index,b_index,&STACK_0,solutions);
          skipSTACK(3);
          return;
        } else {
          if (!equal_pathchar(TheSstring(beispiel)->data[b_index++],c))
            return;
        }
      }
      var uintL b_start_index = b_index;
      loop {
        # Um weniger zu consen, die Fälle abfangen, wo wildcard_diff_ab()
        # gar nichts tut:
        if (m_index == Sstring_length(muster)
            ? b_index == Sstring_length(beispiel)
            : (c = TheSstring(muster)->data[m_index],
               chareq(c,ascii('*')) || chareq(c,ascii('?'))
               || (b_index < Sstring_length(beispiel)
                   && equal_pathchar(TheSstring(beispiel)->data[b_index],c)
           )  )   ) {
          # wildcard_diff_ab() rekursiv aufrufen, mit erweitertem previous:
          pushSTACK(muster); pushSTACK(beispiel);
          pushSTACK(subsstring(beispiel,b_start_index,b_index)); # (SUBSTRING beispiel b_start_index b_index)
          var object new_cons = allocate_cons();
          Car(new_cons) = STACK_0; Cdr(new_cons) = *previous;
          STACK_0 = new_cons; # (CONS ... previous)
          wildcard_diff_ab(STACK_2,STACK_1,m_index,b_index,&STACK_0,solutions);
          skipSTACK(1);
          beispiel = popSTACK(); muster = popSTACK();
        }
        if (b_index == Sstring_length(beispiel))
          break;
        b_index++;
      }
    }

#endif

# DEBUG_TRANSLATE_PATHNAME
#if 0
# all arguments to *_diff are on stack - this should be safe
#define DEBUG_DIFF(f)                                         \
  printf("\n* " #f " [logical: %d]\n",logical);               \
  DOUT("",muster); DOUT("",beispiel); DOUT("",*previous); DOUT("",*solutions)
#else
#define DEBUG_DIFF(f)
#endif
# UPs: Vergleicht jeweils eine Pathname-Komponente ("Beispiel") und
# eine Pathname-Komponente ("Muster").
# can trigger GC
  local void host_diff      (object muster, object beispiel, bool logical,
                             const object* previous, object* solutions);
  local void device_diff    (object muster, object beispiel, bool logical,
                             const object* previous, object* solutions);
  local void directory_diff (object muster, object beispiel, bool logical,
                             const object* previous, object* solutions);
  local void nametype_diff  (object muster, object beispiel, bool logical,
                             const object* previous, object* solutions);
  local void version_diff   (object muster, object beispiel, bool logical,
                             const object* previous, object* solutions);
  local void host_diff(muster,beispiel,logical,previous,solutions)
    var object muster;
    var object beispiel;
    var bool logical;
    var const object* previous;
    var object* solutions;
    {
      DEBUG_DIFF(host_diff);
      #ifdef LOGICAL_PATHNAMES
      if (logical) {
        if (nullp(muster)) {
          push_solution_with(beispiel); return;
        }
        if (!equal(muster,beispiel)) return;
      } else
      #endif
      {
        #if HAS_HOST
        if (nullp(muster)) {
          push_solution_with(beispiel); return;
        }
        if (!equal(muster,beispiel)) return;
        #endif
      }
      #if HAS_HOST
      push_solution_with(S(Khost));
      #else
      push_solution();
      #endif
    }
  local void device_diff(muster,beispiel,logical,previous,solutions)
    var object muster;
    var object beispiel;
    var bool logical;
    var const object* previous;
    var object* solutions;
    {
      DEBUG_DIFF(device_diff);
      #ifdef LOGICAL_PATHNAMES
      if (logical) {
        push_solution(); return;
      }
      #endif
      #if HAS_DEVICE
      #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
      if (nullp(muster) || eq(muster,S(Kwild))) {
        var object string =
          (eq(beispiel,S(Kwild)) ? O(wild_string) : beispiel);
        push_solution_with(string);
        return;
      }
      if (eq(beispiel,S(Kwild))) return;
      #endif
      #if defined(PATHNAME_AMIGAOS) || defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
      if (nullp(muster)) {
        var object string =
          #if defined(PATHNAME_AMIGAOS)
            beispiel;
          #endif
          #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
            (eq(beispiel,S(Kwild)) ? O(wild_string) : beispiel);
          #endif
        push_solution_with(string);
        return;
      }
      if (!equalp(muster,beispiel)) return;
      #else
      if (!equal(muster,beispiel)) return;
      #endif
      push_solution_with(S(Kdevice));
      #else # if HAS_DEVICE
      push_solution();
      #endif
    }
  local void nametype_diff_aux (object muster, object beispiel, bool logical, const object* previous, object* solutions);
  local void nametype_diff_aux(muster,beispiel,logical,previous,solutions)
    var object muster;
    var object beispiel;
    var bool logical;
    var const object* previous;
    var object* solutions;
    {
      #ifdef LOGICAL_PATHNAMES
      if (logical) {
        if (eq(muster,S(Kwild))) {
          var object string =
            (eq(beispiel,S(Kwild)) ? O(wild_string) : beispiel);
          push_solution_with(string);
          return;
        }
        if (eq(beispiel,S(Kwild))) return;
        if (nullp(muster)) {
          if (nullp(beispiel))
            push_solution();
          return;
        }
        if (nullp(beispiel))
          return;
        wildcard_diff(muster,beispiel,previous,solutions);
        return;
      }
      #endif
      #ifdef PATHNAME_NOEXT
      if (nullp(muster)) {
        if (nullp(beispiel))
          push_solution();
        return;
      }
      if (nullp(beispiel))
        return;
      wildcard_diff(muster,beispiel,previous,solutions);
      #endif
    }
  local void subdir_diff(muster,beispiel,logical,previous,solutions)
    var object muster;
    var object beispiel;
    var bool logical;
    var const object* previous;
    var object* solutions;
    {
      DEBUG_DIFF(subdir_diff);
      if (eq(muster,beispiel)) {
        if (eq(beispiel,S(Kwild))) {
          push_solution_with(O(wild_string));
        } else {
          push_solution();
        }
        return;
      }
      #ifdef LOGICAL_PATHNAMES
      if (logical) {
        if (eq(muster,S(Kwild))) {
          var object string =
            (eq(beispiel,S(Kwild)) ? O(wild_string) : beispiel);
          push_solution_with(string);
          return;
        }
        if (eq(beispiel,S(Kwild))) return;
        if (!simple_string_p(muster) || !simple_string_p(beispiel)) return;
        wildcard_diff(muster,beispiel,previous,solutions);
        return;
      }
      #endif
      #ifdef PATHNAME_NOEXT
      if (!simple_string_p(muster) || !simple_string_p(beispiel)) return;
      wildcard_diff(muster,beispiel,previous,solutions);
      #endif
    }
  # rekursive Implementation wegen Backtracking:
  local void directory_diff_ab (object m_list, object b_list, bool logical, const object* previous, object* solutions);
  local void directory_diff_ab(m_list,b_list,logical,previous,solutions)
    var object m_list;
    var object b_list;
    var bool logical;
    var const object* previous;
    var object* solutions;
    {
      # Algorithmus analog zu wildcard_diff_ab.
      var object item;
      if (atomp(m_list)) {
        if (atomp(b_list))
          push_solution();
        return;
      }
      item = Car(m_list); m_list = Cdr(m_list);
      if (!eq(item,S(Kwild_inferiors))) {
        if (atomp(b_list)) return;
        pushSTACK(NIL); pushSTACK(m_list); pushSTACK(Cdr(b_list));
        subdir_diff(item,Car(b_list),logical,previous,&STACK_2);
        # directory_diff_ab() rekursiv aufrufen, mit erweitertem previous:
        while (mconsp(STACK_2)) {
          pushSTACK(Car(STACK_2));
          directory_diff_ab(STACK_(1+1),STACK_(0+1),logical,&STACK_0,solutions);
          skipSTACK(1);
          STACK_2 = Cdr(STACK_2);
        }
        skipSTACK(3);
      } else {
        pushSTACK(b_list); # b_start_list := b_list
        loop {
          # Um weniger zu consen, die Fälle abfangen, wo directory_diff_ab()
          # gar nichts tut:
          if (atomp(m_list)
              ? atomp(b_list)
              : (eq(Car(m_list),S(Kwild_inferiors)) || !atomp(b_list))
             ) {
            # directory_diff_ab() rekursiv aufrufen, mit erweitertem previous:
            pushSTACK(m_list); pushSTACK(b_list);
            pushSTACK(STACK_2); pushSTACK(b_list);
            funcall(L(ldiff),2); # (LDIFF b_start_list b_list)
            pushSTACK(value1);
            {
              var object new_piece = allocate_cons(); # (:DIRECTORY subdir1 ... subdirn)
              Car(new_piece) = S(Kdirectory); Cdr(new_piece) = STACK_0;
              STACK_0 = new_piece;
            }
            {
              var object new_cons = allocate_cons();
              Car(new_cons) = STACK_0; Cdr(new_cons) = *previous;
              STACK_0 = new_cons; # (CONS ... previous)
              directory_diff_ab(STACK_2,STACK_1,logical,&STACK_0,solutions);
              skipSTACK(1);
              b_list = popSTACK(); m_list = popSTACK();
            }
          }
          if (atomp(b_list))
            break;
          b_list = Cdr(b_list);
        }
        skipSTACK(1);
      }
    }
  local void directory_diff(muster,beispiel,logical,previous,solutions)
    var object muster;
    var object beispiel;
    var bool logical;
    var const object* previous;
    var object* solutions;
    {
      DEBUG_DIFF(directory_diff);
      # muster mit O(directory_default) vergleichen:
      if (eq(Car(muster),S(Krelative)) && nullp(Cdr(muster))) {
        # Augment the solution with the beispiel list - starting
        # with :ABSOLUTE or :RELATIVE, it will not fit for "**".
        push_solution_with(beispiel);
        return;
      }
      # Startpoint vergleichen:
      if (!eq(Car(muster),Car(beispiel)))
        return;
      muster = Cdr(muster); beispiel = Cdr(beispiel);
      # subdirs vergleichen:
      directory_diff_ab(muster,beispiel,logical,previous,solutions);
    }
  local void nametype_diff(muster,beispiel,logical,previous,solutions)
    var object muster;
    var object beispiel;
    var bool logical;
    var const object* previous;
    var object* solutions;
    {
      DEBUG_DIFF(nametype_diff);
      if (nullp(muster)) {
        var object string =
          (eq(beispiel,S(Kwild)) ? O(wild_string) : beispiel);
        push_solution_with(string);
        return;
      }
      nametype_diff_aux(muster,beispiel,logical,previous,solutions);
    }
  local void version_diff(muster,beispiel,logical,previous,solutions)
    var object muster;
    var object beispiel;
    var bool logical;
    var const object* previous;
    var object* solutions;
    {
      DEBUG_DIFF(version_diff);
      #ifdef LOGICAL_PATHNAMES
      if (logical) {
        if (nullp(muster) || eq(muster,S(Kwild))) {
          var object string =
            (eq(beispiel,S(Kwild)) ? O(wild_string) :
             integerp(beispiel) ? decimal_string(beispiel) : # (SYS::DECIMAL-STRING beispiel)
             NIL
            );
          push_solution_with(string);
          return;
        }
        if (eq(beispiel,S(Kwild))) return;
        if (!eql(muster,beispiel)) return;
        push_solution();
        return;
      }
      #endif
      #if HAS_VERSION
      if (nullp(muster) || eq(muster,S(Kwild))) {
        var object string =
          (eq(beispiel,S(Kwild)) ? O(wild_string) :
           integerp(beispiel) ? decimal_string(beispiel) : # (SYS::DECIMAL-STRING beispiel)
           NIL;
          );
        push_solution_with(string);
        return;
      }
      if (eq(beispiel,S(Kwild))) return;
      if (!eql(muster,beispiel)) return;
      push_solution();
      #else
      push_solution_with(NIL);
      #endif
    }

  #undef push_solution_with
  #undef push_solution
#undef DEBUG_DIFF

# Jede Substitution ist eine Liste von Normal-Simple-Strings oder Listen.
# (Die Listen entstehen bei :WILD-INFERIORS in directory_diff().)
# Ein Normal-Simple-String passt nur auf '?' oder '*' oder :WILD,
# eine Liste passt nur auf :WILD-INFERIORS.

#ifdef LOGICAL_PATHNAMES

# Beim Einsetzen von Stücken normaler Pathnames in logische Pathnames:
# Umwandlung in Großbuchstaben.
# logical_case(string)
# > string: Normal-Simple-String oder Symbol/Zahl
# < ergebnis: umgewandelter Normal-Simple-String oder dasselbe Symbol/Zahl
# can trigger GC
  local object logical_case (object string);
# Dasselbe, rekursiv wie mit SUBST:
  local object subst_logical_case (object obj);
  local object logical_case(string)
    var object string;
    {
      if (!simple_string_p(string))
        return string;
      return string_upcase(string);
    }
  local object subst_logical_case(obj)
    var object obj;
    {
      if (atomp(obj))
        return logical_case(obj);
      check_STACK(); check_SP();
      pushSTACK(obj);
      # rekursiv für den CAR aufrufen:
      {
        var object new_car = subst_logical_case(Car(obj));
        pushSTACK(new_car);
      }
      # rekursiv für den CDR aufrufen:
      {
        var object new_cdr = subst_logical_case(Cdr(STACK_1));
        if (eq(new_cdr,Cdr(STACK_1)) && eq(STACK_0,Car(STACK_1))) {
          obj = STACK_1; skipSTACK(2); return obj;
        } else {
          # (CONS new_car new_cdr)
          STACK_1 = new_cdr;
          var object new_cons = allocate_cons();
          Car(new_cons) = popSTACK(); Cdr(new_cons) = popSTACK();
          return new_cons;
        }
      }
    }

# Beim Einsetzen von Stücken logischer Pathnames in normale Pathnames:
# Umwandlung in Großbuchstaben.
# customary_case(string)
# > string: Normal-Simple-String oder Symbol/Zahl
# < ergebnis: umgewandelter Normal-Simple-String oder dasselbe Symbol/Zahl
# can trigger GC
  local object customary_case (object string);
# Dasselbe, rekursiv wie mit SUBST:
  local object subst_customary_case (object obj);
  local object customary_case(string)
    var object string;
    {
      if (!simple_string_p(string))
        return string;
      #if defined(PATHNAME_UNIX) || defined(PATHNAME_OS2) || defined(PATHNAME_WIN32) || defined(PATHNAME_RISCOS)
      # Betriebssystem mit Vorzug für Kleinbuchstaben
      return string_downcase(string);
      #endif
      #ifdef PATHNAME_AMIGAOS
      # Betriebssystem mit Vorzug für Capitalize
      string = copy_string(string);
      nstring_capitalize(&TheSstring(string)->data[0],Sstring_length(string));
      return string;
      #endif
    }
  local object subst_customary_case(obj)
    var object obj;
    {
      if (atomp(obj))
        return customary_case(obj);
      check_STACK(); check_SP();
      pushSTACK(obj);
      # rekursiv für den CAR aufrufen:
      {
        var object new_car = subst_customary_case(Car(obj));
        pushSTACK(new_car);
      }
      # rekursiv für den CDR aufrufen:
      {
        var object new_cdr = subst_customary_case(Cdr(STACK_1));
        if (eq(new_cdr,Cdr(STACK_1)) && eq(STACK_0,Car(STACK_1))) {
          obj = STACK_1; skipSTACK(2); return obj;
        } else {
          # (CONS new_car new_cdr)
          STACK_1 = new_cdr;
          var object new_cons = allocate_cons();
          Car(new_cons) = popSTACK(); Cdr(new_cons) = popSTACK();
          return new_cons;
        }
      }
    }

#endif

# Apply substitution SUBST to the MUSTER.
# translate_pathname(&subst,muster)
  local object translate_pathname (object* subst, object muster);
# Pop the CAR of *subst and return it.
#define RET_POP(subst)  \
  { var object ret = Car(*subst); *subst = Cdr(*subst); return ret; }
# translate_host(&subst,muster,logical) etc. liefert den host etc. mit Ersetzungen
# und verkürzen subst passend. Falls nicht passend, liefert es nullobj.
  local object translate_host (object* subst, object muster, bool logical);
  local object translate_device (object* subst, object muster, bool logical);
  local object translate_subdir (object* subst, object muster, bool logical);
  local object translate_directory (object* subst, object muster, bool logical);
  local object translate_nametype (object* subst, object muster, bool logical);
  local object translate_version (object* subst, object muster, bool logical);
  local object translate_host(subst,muster,logical)
    var object* subst;
    var object muster;
    var bool logical;
    {
#define TRAN_HOST(subst,muster)                                         \
        if (nullp(muster) && mconsp(*subst)) {                          \
          if (simple_string_p(Car(*subst)) || nullp(Car(*subst))) {     \
            RET_POP(subst);                                             \
          } else if (eq(Car(*subst),S(Khost))) {                        \
            *subst = Cdr(*subst);                                       \
            return muster;                                              \
          } else                                                        \
            return nullobj;                                             \
        }
      #ifdef LOGICAL_PATHNAMES
      if (logical) {
        TRAN_HOST(subst,muster);
      } else
      #endif
      {
        #if HAS_HOST
        TRAN_HOST(subst,muster);
        #endif
      }
      #if HAS_HOST
      if (eq(Car(*subst),S(Khost)))
        *subst = Cdr(*subst);
      #endif
      return muster;
#undef TRAN_HOST
    }
  local object translate_device(subst,muster,logical)
    var object* subst;
    var object muster;
    var bool logical;
    {
      #if HAS_DEVICE
      #ifdef LOGICAL_PATHNAMES
      if (logical)
        return muster;
      #endif
      #if defined(PATHNAME_AMIGAOS) || defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
      if (nullp(muster) && mconsp(*subst))
      #else
      if ((nullp(muster) || eq(muster,S(Kwild))) && mconsp(*subst))
      #endif
        {
          if (simple_string_p(Car(*subst)) || nullp(Car(*subst))) {
            RET_POP(subst);
          } else if (eq(Car(*subst),S(Kdevice))) {
            *subst = Cdr(*subst);
            return muster;
          } else
            return nullobj;
        }
      if (eq(Car(*subst),S(Kdevice)))
        *subst = Cdr(*subst);
      #endif
      return muster;
    }
  local object translate_nametype_aux (object* subst, object muster, bool logical);
  local object translate_nametype_aux(subst,muster,logical)
    var object* subst;
    var object muster;
    var bool logical;
    {
      if (eq(muster,S(Kwild)) && mconsp(*subst)) {
        if (simple_string_p(Car(*subst)) || nullp(Car(*subst))) {
          var object erg = Car(*subst); *subst = Cdr(*subst);
          return (nullp(erg) ? O(leer_string) : erg);
        } else
          return nullobj;
      }
      if (simple_string_p(muster)) {
        pushSTACK(muster); # muster retten
        var object* muster_ = &STACK_0;
        var uintL len = Sstring_length(muster);
        var uintL index = 0;
        var uintL stringcount = 0; # Anzahl der Strings auf dem Stack
        loop {
          var uintL last_index = index;
          var chart c;
          # Suche nächstes Wildcard-Zeichen:
          muster = *muster_;
          loop {
            if (index == len)
              break;
            c = TheSstring(muster)->data[index];
            if ((chareq(c,ascii('*')) # Wildcard für beliebig viele Zeichen
                 || (!logical && singlewild_char_p(c)) # Wildcard für genau ein Zeichen
                )
                && mconsp(*subst)
               )
              break;
            index++;
          }
          # Nächsten Teilstring auf den Stack:
          pushSTACK(subsstring(muster,last_index,index)); # (SUBSTRING muster last_index index)
          stringcount++;
          # Fertig?
          if (index == len)
            break;
          # Wildcard ersetzen:
          if (simple_string_p(Car(*subst)) || nullp(Car(*subst))) {
            var object s = Car(*subst);
            pushSTACK(nullp(s) ? O(leer_string) : s);
            *subst = Cdr(*subst); stringcount++;
          } else {
            skipSTACK(stringcount+1); return nullobj;
          }
          index++;
        }
        funcall(L(string_concat),stringcount); # (STRING-CONCAT alle Strings)
        skipSTACK(1);
        return value1;
      }
      return muster;
    }
  local object translate_subdir(subst,muster,logical)
    var object* subst;
    var object muster;
    var bool logical;
    {
      #ifdef LOGICAL_PATHNAMES
      if (logical)
        return translate_nametype_aux(subst,muster,logical);
      #endif
      #ifdef PATHNAME_NOEXT
      return translate_nametype_aux(subst,muster,false);
      #endif
    }
  local object translate_directory(subst,muster,logical)
    var object* subst;
    var object muster;
    var bool logical;
    {
      # muster mit O(directory_default) vergleichen:
      if (eq(Car(muster),S(Krelative)) && nullp(Cdr(muster))
          && mconsp(*subst) && mconsp(Car(*subst))) {
        var object list = Car(*subst); *subst = Cdr(*subst);
        if (eq(Car(list),S(Kabsolute)) || eq(Car(list),S(Krelative)))
          return copy_list(list);
        else
          return nullobj;
      }
      var uintL itemcount = 0; # Anzahl der Elemente auf dem Stack
      # Startpoint:
      pushSTACK(Car(muster)); muster = Cdr(muster); itemcount++;
      # subdirs:
      while (consp(muster)) {
        var object item = Car(muster);
        muster = Cdr(muster);
        if (eq(item,S(Kwild_inferiors))) {
          if (mconsp(*subst)) {
            if (consp(Car(*subst)) && eq(Car(Car(*subst)),S(Kdirectory))) {
              var object list = Cdr(Car(*subst)); *subst = Cdr(*subst);
              while (consp(list)) {
                pushSTACK(Car(list)); list = Cdr(list); itemcount++;
              }
            } else {
              skipSTACK(itemcount); return nullobj;
            }
          } else {
            pushSTACK(item); itemcount++;
          }
        } else {
          pushSTACK(muster); # muster retten
          item = translate_subdir(subst,item,logical);
          if (eq(item,nullobj)) { skipSTACK(itemcount+1); return nullobj; }
          muster = STACK_0; STACK_0 = item; itemcount++;
        }
      }
      return listof(itemcount);
    }
  local object translate_nametype(subst,muster,logical)
    var object* subst;
    var object muster;
    var bool logical;
    {
      if (nullp(muster) && mconsp(*subst)) {
        if (simple_string_p(Car(*subst)) || nullp(Car(*subst))) {
          RET_POP(subst);
        } else
          return nullobj;
      }
      return translate_nametype_aux(subst,muster,logical);
    }
  local object translate_version(subst,muster,logical)
    var object* subst;
    var object muster;
    var bool logical;
    {
      #ifdef LOGICAL_PATHNAMES
      if (logical) {
        if ((nullp(muster) || eq(muster,S(Kwild))) && mconsp(*subst)) {
          if (simple_string_p(Car(*subst)) || nullp(Car(*subst))) {
            var object erg = Car(*subst); *subst = Cdr(*subst);
            if (nullp(erg))
              return erg;
            pushSTACK(erg); funcall(L(parse_integer),1);
            return value1;
          } else
            return nullobj;
        }
        return muster;
      }
      #endif
      #if HAS_VERSION
      if ((nullp(muster) || eq(muster,S(Kwild))) && mconsp(*subst)) {
        if (simple_string_p(Car(*subst)) || nullp(Car(*subst))) {
          var object erg = Car(*subst); *subst = Cdr(*subst);
          if (nullp(erg))
            return erg;
          pushSTACK(erg); funcall(L(parse_integer),1);
          return value1;
        } else
          return nullobj;
      }
      return muster;
      #else
      if (mconsp(*subst)) {
        if (simple_string_p(Car(*subst)) || nullp(Car(*subst))) {
          *subst = Cdr(*subst); return NIL;
        } else
          return nullobj;
      }
      return NIL;
      #endif
    }
#undef RET_POP
  local object translate_pathname(subst,muster)
    var object* subst;
    var object muster;
    {
      var bool logical = false;
      var object item;
      pushSTACK(*subst); # subst retten für Fehlermeldung
      pushSTACK(muster);
      #ifdef LOGICAL_PATHNAMES
      if (logpathnamep(muster))
        logical = true;
      #endif
# DEBUG_TRANSLATE_PATHNAME
# this is _not_ safe! you will get segfault if you enable this!
#if 0
#define GET_ITEM(what,xwhat,where,skip)                                 \
 { object xobj = xpathname_##xwhat(logical,where);                      \
   pushSTACK(xobj); /* DOUT can trigger GC! */                          \
   printf("\n *** " #xwhat " [logical: %d]\n",logical);                 \
   DOUT("",*subst); DOUT("",where); DOUT("",xobj);                      \
   item = translate_##what(subst,xobj,logical);                         \
   if (eq(item,nullobj)) { skipSTACK(skip+1); goto subst_error; }       \
   DOUT("",item); popSTACK();                                           \
   pushSTACK(S(K##xwhat)); pushSTACK(item); }
#else
#define GET_ITEM(what,xwhat,where,skip)                                     \
   item = translate_##what(subst,xpathname_##xwhat(logical,where),logical); \
   if (eq(item,nullobj)) { skipSTACK(skip); goto subst_error; }             \
   pushSTACK(S(K##xwhat)); pushSTACK(item)
#endif /* DEBUG_TRANSLATE_PATHNAME */
#define GET_ITEM_S(y,x,w) GET_ITEM(y,x,STACK_(w),w)
      # Argumente für MAKE-PATHNAME zusammenbauen:
      GET_ITEM(host,host,muster,0);
      #if HAS_DEVICE
      GET_ITEM_S(device,device,2);
      #endif
      GET_ITEM_S(directory,directory,2+2*HAS_DEVICE);
      GET_ITEM_S(nametype,name,2+2*HAS_DEVICE+2);
      GET_ITEM_S(nametype,type,2+2*HAS_DEVICE+4);
      GET_ITEM_S(version,version,2+2*HAS_DEVICE+6);
      # Alle Ersetzungsstücke müssen verbraucht werden!
      if (mconsp(*subst)) { skipSTACK(2+2*HAS_DEVICE+8); goto subst_error; }
      # (MAKE-PATHNAME ...) bzw. (SYS::MAKE-LOGICAL-PATHNAME ...) aufrufen:
      #ifdef LOGICAL_PATHNAMES
      if (logical)
        funcall(L(make_logical_pathname),2+2*HAS_DEVICE+8);
      else
      #endif
        funcall(L(make_pathname),2+2*HAS_DEVICE+8);
      skipSTACK(2);
      return value1;
     subst_error: # Error wegen nullobj.
      # Stackaufbau: subst, muster.
      pushSTACK(STACK_1);
      pushSTACK(S(translate_pathname));
      fehler(error,
             GETTEXT("~: replacement pieces ~ do not fit into ~")
            );
    }
#undef GET_ITEM
#undef GET_ITEM_S

LISPFUN(translate_pathname,3,0,norest,key,2, (kw(all),kw(merge)))
# (TRANSLATE-PATHNAME beispiel muster1 muster2 [:all] [:merge]), CLtL2 S. 624
# :all = T --> liefere eine Liste aller passenden Pathnames
# :all = NIL --> Error, falls mehr als ein Pathname passt
# :merge = NIL --> letzten MERGE-PATHNAMES Schritt überspringen
  {
    # Stackaufbau: beispiel, muster1, muster2, all, merge.
    var bool logical = false; # Flag, ob beispiel und muster logische Pathnames sind
    var bool logical2 = false; # Flag, ob muster2 ein logischer Pathname ist
    STACK_4 = coerce_xpathname(STACK_4);
    STACK_3 = coerce_xpathname(STACK_3);
    STACK_2 = coerce_xpathname(STACK_2);
    #ifdef LOGICAL_PATHNAMES
    if (logpathnamep(STACK_4) && logpathnamep(STACK_3)) {
      logical = true;
    } else {
      # nicht beides logische Pathnames -> erst in normale Pathnames umwandeln:
      STACK_4 = coerce_pathname(STACK_4);
      STACK_3 = coerce_pathname(STACK_3);
    }
    if (logpathnamep(STACK_2))
      logical2 = true;
    #endif
    # 1. Schritt: Liste aller passenden Substitutionen bilden.
    pushSTACK(NIL); pushSTACK(NIL);
    SHOW_STACK("before host_diff",6);
    host_diff(xpathname_host(logical,STACK_(3+2)),
              xpathname_host(logical,STACK_(4+2)),
              logical,&STACK_1,&STACK_0);
    while (mconsp(STACK_0)) {
      pushSTACK(Car(STACK_0)); pushSTACK(NIL);
      SHOW_STACK("before device_diff",8);
      device_diff(xpathname_device(logical,STACK_(3+4)),
                  xpathname_device(logical,STACK_(4+4)),
                  logical,&STACK_1,&STACK_0);
      while (mconsp(STACK_0)) {
        pushSTACK(Car(STACK_0)); pushSTACK(NIL);
        SHOW_STACK("before directory_diff",10);
        directory_diff(xpathname_directory(logical,STACK_(3+6)),
                       xpathname_directory(logical,STACK_(4+6)),
                       logical,&STACK_1,&STACK_0);
        while (mconsp(STACK_0)) {
          pushSTACK(Car(STACK_0)); pushSTACK(NIL);
          SHOW_STACK("before nametype_diff1",12);
          nametype_diff(xpathname_name(logical,STACK_(3+8)),
                        xpathname_name(logical,STACK_(4+8)),
                        logical,&STACK_1,&STACK_0);
          while (mconsp(STACK_0)) {
            pushSTACK(Car(STACK_0)); pushSTACK(NIL);
            SHOW_STACK("before nametype_diff2",14);
            nametype_diff(xpathname_type(logical,STACK_(3+10)),
                          xpathname_type(logical,STACK_(4+10)),
                          logical,&STACK_1,&STACK_0);
            while (mconsp(STACK_0)) {
              pushSTACK(Car(STACK_0));
              SHOW_STACK("before version_diff",15);
              version_diff(xpathname_version(logical,STACK_(3+11)),
                           xpathname_version(logical,STACK_(4+11)),
                           logical,&STACK_0,&STACK_10);
              SHOW_STACK("after version_diff",15);
              skipSTACK(1);
              STACK_0 = Cdr(STACK_0);
            }
            SHOW_STACK("after nametype_diff2",14);
            skipSTACK(2);
            STACK_0 = Cdr(STACK_0);
          }
          SHOW_STACK("after nametype_diff1",12);
          skipSTACK(2);
          STACK_0 = Cdr(STACK_0);
        }
        SHOW_STACK("after directory_diff",10);
        skipSTACK(2);
        STACK_0 = Cdr(STACK_0);
      }
      SHOW_STACK("after device_diff",8);
      skipSTACK(2);
      STACK_0 = Cdr(STACK_0);
    }
    SHOW_STACK("after host_diff",6);
    skipSTACK(1);
    # Stackaufbau: ..., solutions.
    if (matomp(STACK_0)) {
      pushSTACK(STACK_(3+1));
      pushSTACK(STACK_(4+1+1));
      pushSTACK(S(translate_pathname));
      fehler(error,
             GETTEXT("~: ~ is not a specialization of ~")
            );
    }
    # 2.,3. Schritt:
    pushSTACK(NIL); # pathnames := '()
    while (mconsp(STACK_1)) { # solutions durchgehen
      var object solutions = STACK_1;
      STACK_1 = Cdr(solutions);
      {
        var object solution = reverse(Car(solutions)); # Liste solution umdrehen
        # 2. Schritt: Substitution in muster2 einfügen.
        #ifdef LOGICAL_PATHNAMES
        # Groß-/Kleinschreibung passend konvertieren:
        if (!logical) {
          if (logical2)
            solution = subst_logical_case(solution);
        } else {
          if (!logical2)
            solution = subst_customary_case(solution);
        }
        #endif
        pushSTACK(solution);
        STACK_0 = translate_pathname(&STACK_0,STACK_(2+1+2));
      }
      # 3. Schritt: (MERGE-PATHNAMES modifiziertes_muster2 beispiel :WILD T)
      if (!nullp(STACK_(0+1+2))) # :MERGE-Argument abfragen
        if (has_some_wildcards(STACK_0)) { # evtl. ist MERGE-PATHNAMES unnötig
          pushSTACK(STACK_(4+1+2)); pushSTACK(unbound);
          pushSTACK(S(Kwild)); pushSTACK(T);
          funcall(L(merge_pathnames),5);
          pushSTACK(value1);
        }
      # (PUSH pathname pathnames)
      {
        var object new_cons = allocate_cons();
        Car(new_cons) = popSTACK(); Cdr(new_cons) = STACK_0;
        STACK_0 = new_cons;
      }
    }
    # 4. Schritt: (DELETE-DUPLICATES pathnames :TEST #'EQUAL)
    pushSTACK(S(Ktest)); pushSTACK(L(equal));
    funcall(L(delete_duplicates),3);
    # Stackaufbau: ..., nil.
    if (eq(STACK_(1+1),unbound) || nullp(STACK_(1+1))) { # :ALL-Argument abfragen
      if (mconsp(Cdr(value1))) {
        pushSTACK(value1);
        pushSTACK(STACK_(2+2));
        pushSTACK(STACK_(3+3));
        pushSTACK(STACK_(4+4));
        pushSTACK(S(translate_pathname));
        fehler(error,
               GETTEXT("(~ ~ ~ ~) is ambiguous: ~")
              );
      }
      value1 = Car(value1);
    }
    mv_count=1;
    skipSTACK(5+1);
  }

# UP: Stellt fest, ob der Name eines Pathname =NIL ist.
# namenullp(pathname)
# > pathname: nicht-Logical Pathname
  # local bool namenullp (object pathname);
  # local bool namenullp(pathname)
  #   { return nullp(ThePathname(pathname)->pathname_name); }
  #define namenullp(path)  (nullp(ThePathname(path)->pathname_name))

# Fehler, wenn ein Directory nicht existiert
# > obj: Pathname oder (besser) fehlerhafte Komponente
  nonreturning_function(local, fehler_dir_not_exists, (object obj));
  local void fehler_dir_not_exists(obj)
    var object obj;
    {
      pushSTACK(obj); # Wert für Slot PATHNAME von FILE-ERROR
      pushSTACK(obj);
      fehler(file_error,
             GETTEXT("nonexistent directory: ~")
            );
    }

# Fehler, wenn eine Datei bereits existiert
# > caller: Aufrufer (ein Symbol)
# > pathname: Pathname
  nonreturning_function(local, fehler_file_exists, (object caller, object pathname));
  local void fehler_file_exists(caller,pathname)
    var object caller;
    var object pathname;
    {
      pushSTACK(pathname); # Wert für Slot PATHNAME von FILE-ERROR
      pushSTACK(pathname);
      pushSTACK(caller);
      fehler(file_error,
             GETTEXT("~: File ~ already exists")
            );
    }

#ifdef LOGICAL_PATHNAMES
# Ein "absoluter Pathname" ist stets ein nicht-Logical Pathname, evtl.
# mit weiteren Einschränkungen.
#endif

#if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)

# Ein "absoluter Pathname" ist ein Pathname, bei dem Device ein überprüfter
# String ist und Directory kein :RELATIVE, :CURRENT, :PARENT enthält.

# UP: Liefert den Namestring eines Pathname fürs Betriebssystem.
# OSnamestring(dir_namestring)
# > STACK_0: nicht-Logical Pathname
# > dir_namestring: Directory-Namestring (für DOS)
# < ergebnis: Namestring (für DOS)
# can trigger GC
  local object OSnamestring (object dir_namestring);
  local object OSnamestring(dir_namestring)
    var object dir_namestring;
    {
      var uintC stringcount;
      pushSTACK(dir_namestring); # Directory-Namestring als 1. String
      stringcount = file_namestring_parts(STACK_(0+1)); # Strings zum Filenamen
      return string_concat(1+stringcount); # zusammenhängen
    }

#ifdef EMUNIX

# Working Directory auf einem gegebenen Drive abfragen:
# getwdof(&buf,drive)
# > uintB* &buf: Adresse eines Path-Buffers
# > uintB drive: Laufwerk (0=A, 1=B, ...)
# < ergebnis: <0 falls Fehler
  #define getwdof(buf,drive)  _getcwd(buf,drive)

# Liefert das aktuelle Directory auf einem Laufwerk.
# getwd_of(path,drive)
# > uintB drive: Laufwerks-(groß-)buchstabe
# > uintB* path: Platz fürs aktuelle Directory
# < path: Pfad des aktuellen Directories, mit '/' als Trennzeichen und als Anfang
# < ergebnis: <0 falls Fehler
  #define getwd_of(path,drive)  _getcwd1(path,drive)

#endif # EMUNIX

# UP: Stellt fest, ob ein Laufwerk existiert.
# > uintB drive: Laufwerks-(groß-)buchstabe
# < bool ergebnis: ob dieses Laufwerk existiert und ansprechbar ist
  local bool good_drive (uintB drive);
  #ifdef EMUNIX
  local bool good_drive(drive)
    var uintB drive;
    {
      # Methode (siehe HELPPC/misc.txt):
      # 1. save current drive  (INT 0x21,0x19)
      # 2. set current drive  (INT 0x21,0xE)
      # 3. get current drive  (INT 0x21,0x19)
      # 4. if current drive == drive requested
      #       then drive exists
      #       else drive doesn't exist
      # 5. reset original drive  (INT 0x21,0xE)
      var bool result;
      begin_system_call();
      {
        var uintB orig_drive = _getdrive();
        _chdrive(drive);
        result = (_getdrive() == drive);
        _chdrive(orig_drive);
      }
      end_system_call();
      return result;
      # Alternative:
      # {
      #   var uintB drv[3];
      #   var uintB fsys[16];
      #   drv[0] = drive; drv[1] = ':'; drv[2] = '\0';
      #   begin_system_call();
      #   var int result = _filesys(drv,&fsys,sizeof(fsys));
      #   end_system_call();
      #   return (result==0);
      # }
    }
  #endif
  #ifdef WIN32_NATIVE
  local bool good_drive(drive)
    var uintB drive;
    {
      var char rootpath[4];
      var DWORD result;
      rootpath[0] = drive;
      rootpath[1] = ':';
      rootpath[2] = '\\';
      rootpath[3] = '\0';
      begin_system_call();
      result = GetDriveType(rootpath);
      switch (result) {
        case DRIVE_UNKNOWN:
          end_system_call();
          return false;
        case DRIVE_NO_ROOT_DIR:
          # Distinguish NFS mounts from nonassigned drive letters:
          result = GetFileAttributes(rootpath);
          end_system_call();
          return !(result==0xFFFFFFFF);
        default:
          end_system_call();
          return true;
      }
    }
  #if 0
  # The following fails to recognize some (but not all) NFS mounts on WinNT.
  local bool good_drive_notsogood(drive)
    var uintB drive;
    {
      var DWORD drives_bitmask;
      begin_system_call();
      drives_bitmask = GetLogicalDrives();
      end_system_call();
      return ((drives_bitmask & ((DWORD)1 << (drive-'A'))) != 0);
    }
  #endif
  #endif

# UP: Liefert das aktuelle Drive.
# < char drive: Laufwerks-(groß-)buchstabe
  local char default_drive (void);
 #ifdef EMUNIX
  local char default_drive()
    {
      var uintB result;
      begin_system_call();
      result = _getdrive();
      end_system_call();
      return result;
    }
 #endif
 #ifdef WIN32_NATIVE
  local char default_drive()
    {
      var DWORD path_buflen = _MAX_PATH;
      var char* path_buffer = (char*)alloca(path_buflen);
      var DWORD result;
      begin_system_call();
      result = GetCurrentDirectory(path_buflen,path_buffer);
      if (!result) { OS_error(); }
      if (result >= path_buflen) {
        path_buflen = result; path_buffer = (char*)alloca(path_buflen);
        result = GetCurrentDirectory(path_buflen,path_buffer);
        if (!result) { OS_error(); }
      }
      end_system_call();
      ASSERT(path_buffer[1]==':');
      ASSERT(path_buffer[2]=='\\');
      return up_case(path_buffer[0]);
    }
 #endif

# UP: Liefert das aktuelle Directory auf einem gegebenen Drive.
# > uintB drive: Laufwerks-(groß-)buchstabe
# > object pathname: Pathname (für Fehlermeldungszwecke)
# < ergebnis: aktuelles Directory (als Pathname)
# can trigger GC
  local object default_directory_of (uintB drive, object pathname);
  local object default_directory_of(drive,pathname)
    var uintB drive;
    var object pathname;
    # Working Directory (von DOS) ist das aktuelle Directory:
    {
      #if defined(WIN32_NATIVE)
        var char currpath[4];
        var DWORD path_buflen = _MAX_PATH;
        var char* path_buffer = (char*)alloca(path_buflen+1);
        var char* dummy;
        var DWORD result;
        currpath[0] = drive;
        currpath[1] = ':';
        currpath[2] = '.'; # this dot is actually not needed
        currpath[3] = '\0';
        begin_system_call();
        result = GetFullPathName(currpath,path_buflen,path_buffer,&dummy);
        if (!result) { end_system_call(); OS_file_error(pathname); }
        if (result >= path_buflen) {
          path_buflen = result; path_buffer = (char*)alloca(path_buflen+1);
          result = GetFullPathName(currpath,path_buflen,path_buffer,&dummy);
          if (!result) { end_system_call(); OS_file_error(pathname); }
        }
        end_system_call();
        # evtl. noch ein '\' am Schluss anfügen:
        {
          var char* path_end = &path_buffer[asciz_length(path_buffer)];
          if (!(path_end[-1]=='\\')) { path_end[0] = '\\'; path_end[1] = '\0'; }
        }
      #else
        var char path_buffer[3+MAXPATHLEN]; # vgl. GETWD(3)
        path_buffer[0] = drive; path_buffer[1] = ':';
        # Working Directory in path_buffer ablegen:
        begin_system_call();
        getwd_of(&path_buffer[2],drive);
        end_system_call();
      #endif
      # Hack von DJ (siehe GO32/EXPHDLR.C) und EM (siehe LIB/MISC/_GETCWD1.C):
      # wandelt alle '\' in '/' und alle Groß- in Kleinbuchstaben (nur Kosmetik,
      # da DOS und unser PARSE-NAMESTRING auch Filenamen mit '/' statt '\'
      # verstehen).
      # in Pathname umwandeln:
      return asciz_dir_to_pathname(&path_buffer[0],O(pathname_encoding));
    }

# UP: Füllt Default-Drive und Default-Directory in einen Pathname ein.
# use_default_dir(pathname)
# > pathname: nicht-Logical Pathname mit Device /= :WILD
# < ergebnis: neuer absoluter Pathname
# can trigger GC
  local object use_default_dir (object pathname);
  local object use_default_dir(pathname)
    var object pathname;
    {
      # erst den Pathname kopieren:
      pathname = copy_pathname(pathname);
      pushSTACK(pathname);
      # Stackaufbau: pathname.
      # Default fürs Device:
      #if HAS_HOST # PATHNAME_WIN32
      if (nullp(ThePathname(pathname)->pathname_host))
      #endif
        if (nullp(ThePathname(pathname)->pathname_device)) { # kein Device angegeben?
          # Nimm das Default-Drive stattdessen:
          ThePathname(pathname)->pathname_device = O(default_drive);
        }
      # Default fürs Directory:
      {
        var object subdirs = ThePathname(pathname)->pathname_directory;
        # Fängt pathname-directory mit :RELATIVE an?
        if (eq(Car(subdirs),S(Krelative))) {
          # ja -> Ersetze :RELATIVE durch das Default-Directory:
          pushSTACK(Cdr(subdirs));
          #if HAS_HOST # PATHNAME_WIN32
          if (!nullp(ThePathname(pathname)->pathname_host)) {
            # We don't have the concept of a current directory on a
            # remote host. Simply use :ABSOLUTE instead of :RELATIVE.
            subdirs = allocate_cons();
            Car(subdirs) = S(Kabsolute);
            Cdr(subdirs) = popSTACK();
          } else
          #endif
          {
            var uintB drive = as_cint(TheSstring(ThePathname(pathname)->pathname_device)->data[0]);
            var object default_dir = default_directory_of(drive,pathname);
            # default_dir (ein Pathname) ist fertig.
            # Ersetze :RELATIVE durch default-subdirs, d.h.
            # bilde  (append default-subdirs (cdr subdirs))
            #      = (nreconc (reverse default-subdirs) (cdr subdirs))
            var object temp = ThePathname(default_dir)->pathname_directory;
            temp = reverse(temp);
            subdirs = nreconc(temp,popSTACK());
          }
        }
        # Liste durchgehen und dabei neu aufconsen, dabei '.\' und '..\'
        # und '...\' verarbeiten (nicht dem DOS überlassen):
        pushSTACK(subdirs);
        pushSTACK(NIL);
        # Stackaufbau: Pathname, subdir-oldlist, subdir-newlist.
        while (mconsp(STACK_1)) { # Bis oldlist am Ende ist:
          var object subdir = Car(STACK_1); # nächstes subdir
          if (equal(subdir,O(punkt_string))) {
            # = :CURRENT -> newlist unverändert lassen
          } elif (equal(subdir,O(punktpunkt_string))) {
            # = :PARENT -> newlist um eins verkürzen:
            if (matomp(Cdr(STACK_0))) { # newlist (bis auf :ABSOLUTE) leer ?
              # :PARENT von "\" aus liefert Error
              pushSTACK(STACK_2); # Wert für Slot PATHNAME von FILE-ERROR
              pushSTACK(O(backslash_string)); # "\\"
              pushSTACK(directory_namestring(STACK_(2+2))); # Directory von pathname
              fehler(file_error,
                     GETTEXT("no directory ~ above ~")
                    );
            }
            if (eq(Car(STACK_0),S(Kwild_inferiors))) { # newlist fängt mit '...\' an ?
              # :PARENT von "...\" aus liefert Error
              pushSTACK(STACK_2); # Wert für Slot PATHNAME von FILE-ERROR
              pushSTACK(directory_namestring(STACK_(2+1))); # Directory von pathname
              fehler(file_error, # '"..\\" nach "...\\" ist unzulässig: ~'
                     GETTEXT("\"..\\\\\" after \"...\\\\\" is invalid: ~")
                    );
            }
            STACK_0 = Cdr(STACK_0);
          } else { # (auch wenn :ABSOLUTE !)
            # newlist um eins verlängern:
            pushSTACK(subdir);
            var object new_cons = allocate_cons();
            Car(new_cons) = popSTACK();
            Cdr(new_cons) = STACK_0;
            STACK_0 = new_cons;
          }
          STACK_1 = Cdr(STACK_1);
        }
        subdirs = nreverse(popSTACK()); # newlist, wieder umdrehen
        skipSTACK(1);
        # Stackaufbau: pathname.
        pathname = popSTACK();
        ThePathname(pathname)->pathname_directory = subdirs; # in den Pathname eintragen
      }
      return pathname;
    }

# UP: Stellt sicher, dass das Directory eines Pathname existiert.
# Sonst Fehlermeldung.
# assure_dir_exists(links_resolved,tolerantp)
# > STACK_0: absoluter Pathname ohne Wildcards im Directory
# > links_resolved: Flag, ob im Directory des Pathname schon alle Links
#     aufgelöst sind und es als existierend bekannt ist
# > tolerantp: Flag, ob ein Fehler vermieden werden soll
# < ergebnis:
#     falls Name=NIL: Directory-Namestring (für DOS)
#     falls Name/=NIL: Namestring (für DOS)
#     falls tolerantp evtl.: nullobj
# can trigger GC
  local object assure_dir_exists (bool links_resolved, bool tolerantp);
  local object assure_dir_exists(links_resolved,tolerantp)
    var bool links_resolved;
    var bool tolerantp;
    {
      var object dir_namestring = directory_namestring(STACK_0);
      if (!links_resolved) {
        # Existenztest:
        #ifdef MSDOS
          # 1. Subdir-List leer -> OK
          #    (Muss abgefangen werden, denn stat() auf Rootdir liefert Fehler.)
          # 2. OS/2: Subdir-List = ("PIPE") -> OK
          #    (Dieses Spezialverzeichnis "\\PIPE\\" ist in Wirklichkeit keines.)
          # 3. Sonst stat() probieren.
          if (!(nullp(Cdr(ThePathname(STACK_0)->pathname_directory))
                #ifdef PATHNAME_OS2
                || equal(Cdr(ThePathname(STACK_0)->pathname_directory),O(pipe_subdirs))
                #endif
             ) ) {
            var struct stat statbuf;
            with_sstring(dir_namestring,O(pathname_encoding),path,len, {
              ASSERT((len > 0) && (path[len-1] == '\\'));
              path[len-1] = '\0'; # '\' am Schluss durch Nullbyte ersetzen
              begin_system_call();
              if (stat(path,&statbuf) < 0) {
                if (!(tolerantp && (errno==ENOENT))) {
                  end_system_call(); OS_file_error(STACK_0);
                }
                end_system_call();
                FREE_DYNAMIC_ARRAY(path);
                return nullobj;
              }
              end_system_call();
            });
            if (!S_ISDIR(statbuf.st_mode)) { # gefundene Datei kein Unterdirectory ?
              if (tolerantp) return nullobj;
              fehler_dir_not_exists(dir_namestring);
            }
          }
        #endif
        #ifdef WIN32_NATIVE
          var DWORD fileattr;
          with_sstring_0(dir_namestring,O(pathname_encoding),path, {
            if (!nullp(Cdr(ThePathname(STACK_0)->pathname_directory))) {
              var uintL len = Sstring_length(dir_namestring);
              ASSERT((len > 0) && (path[len-1] == '\\'));
              path[len-1] = '\0'; # '\' am Schluss durch Nullbyte ersetzen
            }
            begin_system_call();
            fileattr = GetFileAttributes(path);
            if (fileattr == 0xFFFFFFFF) {
              if (!(tolerantp && (GetLastError()==ERROR_FILE_NOT_FOUND || GetLastError()==ERROR_PATH_NOT_FOUND || GetLastError()==ERROR_BAD_NETPATH))) {
                end_system_call(); OS_file_error(STACK_0);
              }
              end_system_call();
              FREE_DYNAMIC_ARRAY(path);
              return nullobj;
            }
            end_system_call();
          });
          if (!(fileattr & FILE_ATTRIBUTE_DIRECTORY)) { # gefundene Datei kein Unterdirectory ?
            if (tolerantp) return nullobj;
            fehler_dir_not_exists(dir_namestring);
          }
        #endif
      }
      if (namenullp(STACK_0))
        return dir_namestring;
      else
        return OSnamestring(dir_namestring);
    }

# UP: Liefert den Directory-Namestring eines Pathname unter der Annahme,
#     dass das Directory dieses Pathname existiert.
# assume_dir_exists()
# > STACK_0: absoluter Pathname ohne Wildcards im Directory
# < ergebnis:
#     falls Name=NIL: Directory-Namestring (für DOS)
#     falls Name/=NIL: Namestring (für DOS)
# can trigger GC
  global object assume_dir_exists (void);
  global object assume_dir_exists()
    {
      return assure_dir_exists(true,false);
    }

#endif

#ifdef PATHNAME_AMIGAOS

# UP: Liefert den Truename eines Directory-Locks.
# > set_break_sem_4(): schon ausgeführt
# > lock: Directory-Lock, wird freigegeben
# < ergebnis: Directory (als Pathname)
# can trigger GC
  local object directory_truename (BPTR lock);
  local object directory_truename(lock)
    var BPTR lock;
    {
      # Von hier aus hochhangeln:
      pushSTACK(NIL); # Subdir-Liste := NIL
      {
        var LONGALIGNTYPE(struct FileInfoBlock) fib;
        var struct FileInfoBlock * fibptr = LONGALIGN(&fib);
        loop {
          # Directory selbst ansehen:
          begin_system_call();
          {
            var LONG ergebnis = Examine(lock,fibptr);
            if (!ergebnis) { UnLock(lock); OS_error(); }
            end_system_call();
          }
          # seinen Namen verwenden:
          var object name = asciz_to_string(&fibptr->fib_FileName[0],O(pathname_encoding));
          # zum Parent-Directory hochsteigen:
          var BPTR parentlock;
          begin_system_call();
          parentlock = ParentDir(lock);
          UnLock(lock);
          end_system_call();
          if (!(parentlock==BPTR_NULL)) {
            # name ist der Name eines Subdirectories
            # vor die Subdir-Liste pushen:
            pushSTACK(name);
            {
              var object new_cons = allocate_cons();
              Car(new_cons) = popSTACK();
              Cdr(new_cons) = STACK_0;
              STACK_0 = new_cons;
            }
            lock = parentlock; # und vom Parent Directory aus weitermachen
          } else {
            begin_system_call();
            if (IoErr()) { OS_error(); } # Fehler aufgetreten?
            end_system_call();
            # name ist der Name eines DOS-Volumes.
            pushSTACK(name);
            break;
          }
        }
      }
      clr_break_sem_4(); # Unterbrechungen wieder zulassen
      # Stackaufbau: subdirs, devicename.
      {
        # subdirs mit :ABSOLUTE anfangen lassen:
        var object new_cons = allocate_cons();
        Car(new_cons) = S(Kabsolute); Cdr(new_cons) = STACK_1;
        STACK_1 = new_cons;
      }
      var object default_dir = allocate_pathname(); # neuer Pathname mit Name=NIL und Typ=NIL
      ThePathname(default_dir)->pathname_device = popSTACK();
      ThePathname(default_dir)->pathname_directory = popSTACK();
      return default_dir;
    }

# UP: Liefert das aktuelle Directory.
# < ergebnis: aktuelles Directory (als Pathname)
# can trigger GC
  local object default_directory (void);
  local object default_directory()
    {
      # Lock fürs aktuelle Directory holen:
      set_break_sem_4(); # Unterbrechungen währenddessen verhindern
      begin_system_call();
      var BPTR lock = Lock("",ACCESS_READ);
      if (lock==BPTR_NULL) {
        if (!(IoErr()==ERROR_OBJECT_NOT_FOUND)) { clr_break_sem_4(); OS_error(); }
        end_system_call(); clr_break_sem_4();
        pushSTACK(unbound); # "Wert" für Slot PATHNAME von FILE-ERROR
        fehler(file_error,
               GETTEXT("Couldn't access current directory")
              );
      }
      end_system_call();
      return directory_truename(lock); # macht clr_break_sem_4(); und UnLock(lock);
    }

# UP: Füllt Default-Directory in einen Pathname ein.
# use_default_dir(pathname)
# > pathname: nicht-Logical Pathname
# < ergebnis: neuer absoluter Pathname
# can trigger GC
  local object use_default_dir (object pathname);
  local object use_default_dir(pathname)
    var object pathname;
    {
      # erst den Pathname kopieren:
      pathname = copy_pathname(pathname);
      # Dann das Default-Directory in den Pathname einbauen:
      {
        var object subdirs = ThePathname(pathname)->pathname_directory;
        # Fängt pathname-directory mit :RELATIVE an?
        if (eq(Car(subdirs),S(Krelative))) {
          # ja -> Ersetze :RELATIVE durch default-subdirs, d.h.
          # bilde  (append default-subdirs (cdr subdirs))
          #      = (nreconc (reverse default-subdirs) (cdr subdirs))
          pushSTACK(pathname);
          pushSTACK(Cdr(subdirs));
          var object temp = default_directory();
          temp = ThePathname(temp)->pathname_directory;
          temp = reverse(temp);
          subdirs = nreconc(temp,popSTACK());
          pathname = popSTACK();
          # in den Pathname eintragen:
          ThePathname(pathname)->pathname_directory = subdirs;
        }
      }
      return pathname;
    }

# UP: Macht aus einem Directory-Namestring einen, der für AMIGAOS geeignet ist.
# OSdirnamestring(namestring)
# > namestring: neu erzeugter Directory-Namestring, mit '/' oder ':' am
#               Schluss, ein Normal-Simple-String
# < ergebnis: Namestring zu diesem Directory, im AmigaOS-Format: letzter '/'
#             gestrichen, falls überflüssig, ein Normal-Simple-String
# can trigger GC
  local object OSdirnamestring (object namestring);
  local object OSdirnamestring(namestring)
    var object namestring;
    {
      var uintL len = Sstring_length(namestring);
      if (len==0) goto ok; # Leerstring -> nichts streichen
      var chart ch = TheSstring(namestring)->data[len-1];
      if (!chareq(ch,ascii('/'))) goto ok; # kein '/' am Schluss -> nichts streichen
      if (len==1) goto ok; # "/" bedeutet Parent -> nicht streichen
      ch = TheSstring(namestring)->data[len-2];
      if (chareq(ch,ascii('/')) || chareq(ch,ascii(':'))) # davor ein '/' oder ':'
        goto ok; # -> bedeutet Parent -> nicht streichen
      # '/' am Schluss streichen:
        namestring = subsstring(namestring,0,len-1);
     ok: # nichts streichen
      return namestring;
    }

# UP: Stellt sicher, dass das Directory eines Pathname existiert.
# assure_dir_exists(tolerantp)
# > STACK_0: nicht-Logical Pathname, bei dem Directory kein :RELATIVE enthält.
# > links_resolved: Flag, ob im Directory des Pathname schon alle Links
#     aufgelöst sind und es als existierend bekannt ist
# > tolerantp: Flag, ob ein Fehler vermieden werden soll
# > subr_self: Aufrufer (ein SUBR)
# < STACK_0: (evtl. derselbe) Pathname, aber aufgelöst.
# < ergebnis:
#     falls Name=NIL: Directory-Namestring (für AMIGAOS, mit '/' am Schluss)
#     falls Name/=NIL: Namestring (für AMIGAOS)
#     falls tolerantp evtl.: nullobj
# < filestatus: Falls Name/=NIL: NULL falls das File nicht existiert,
#                                sonst ein Pointer auf eine STAT-Information.
# can trigger GC
  local var struct FileInfoBlock * filestatus;
  local object assure_dir_exists (bool links_resolved, bool tolerantp);
  local object assure_dir_exists(links_resolved,tolerantp)
    var bool links_resolved;
    var bool tolerantp;
    {
      if (!links_resolved) {
        # Zur Auflösung von :PARENTs, die über Root hinaussteigen,
        # müssen wir das Betriebssystem bemühen. Daher:
        var object dir_namestring = directory_namestring(STACK_0);
        pushSTACK(dir_namestring);
        dir_namestring = OSdirnamestring(dir_namestring); # ohne überflüssigen '/' am Schluss
        with_sstring_0(dir_namestring,O(pathname_encoding),dir_namestring_asciz, {
          # Lock für dieses Directory holen:
          set_break_sem_4(); # Unterbrechungen währenddessen verhindern
          begin_system_call();
          var BPTR lock = Lock(dir_namestring_asciz,ACCESS_READ);
          if (lock==BPTR_NULL) {
            var LONG errcode = IoErr();
            end_system_call();
            FREE_DYNAMIC_ARRAY(dir_namestring_asciz);
            switch (errcode) {
              case ERROR_OBJECT_NOT_FOUND:
                clr_break_sem_4();
                if (tolerantp) { skipSTACK(1); return nullobj; }
                fehler_dir_not_exists(STACK_0);
              case ERROR_ACTION_NOT_KNOWN:
                # Ein Device, bei dem man keine Locks für Subdirectories holen
                # kann! Hierbei muss es sich wohl um ein spezielles Device handeln
                # (PIPE, CON, AUX, etc.).
                # Wir stoppen die Subdirectory-Überprüfungen. Nicht einmal mehr
                # Examine() rufen wir auf. Wir gehen im Gegenteil davon aus, dass
                # das File im gewöhnlichen Sinne (noch) nicht existiert.
                clr_break_sem_4(); # Unterbrechungen zulassen, da wir nun doch kein Lock belegt haben
                if (namenullp(STACK_(0+1))) { # kein File angesprochen?
                  return popSTACK(); # ja -> fertig
                } else {
                  var uintC stringcount = 1; # directory_namestring schon auf dem STACK
                  stringcount += file_namestring_parts(STACK_(0+1)); # Strings für den Filename
                  var object namestring = string_concat(stringcount); # zusammenhängen
                  filestatus = (struct FileInfoBlock *)NULL; # File existiert nicht, sagen wir
                  return namestring;
                }
              default:
                OS_file_error(STACK_(0+1));
            }
          }
          end_system_call();
          dir_namestring = popSTACK();
          # und überprüfen, ob's ein Directory ist:
          {
            var LONGALIGNTYPE(struct FileInfoBlock) fib;
            var struct FileInfoBlock * fibptr = LONGALIGN(&fib);
            begin_system_call();
            var LONG ergebnis = Examine(lock,fibptr);
            if (!ergebnis) {
              UnLock(lock);
              end_system_call(); clr_break_sem_4();
              FREE_DYNAMIC_ARRAY(dir_namestring_asciz);
              OS_file_error(STACK_0);
            }
            if (!(fibptr->fib_DirEntryType >= 0)) { # etwa kein Directory?
              UnLock(lock);
              end_system_call(); clr_break_sem_4();
              FREE_DYNAMIC_ARRAY(dir_namestring_asciz);
              if (tolerantp) { return nullobj; }
              # STACK_0 = Wert für Slot PATHNAME von FILE-ERROR
              pushSTACK(dir_namestring);
              pushSTACK(TheSubr(subr_self)->name);
              fehler(file_error,
                     GETTEXT("~: ~ names a file, not a directory")
                    );
            }
            end_system_call();
          }
          # Lock zum Truename machen:
          var object new_pathname = directory_truename(lock); # macht clr_break_sem_4();
          var object old_pathname = STACK_0;
          ThePathname(new_pathname)->pathname_name = ThePathname(old_pathname)->pathname_name;
          ThePathname(new_pathname)->pathname_type = ThePathname(old_pathname)->pathname_type;
          STACK_0 = new_pathname;
        });
      }
      var object pathname = STACK_0;
      # Information zum angesprochenen File holen:
      if (namenullp(pathname)) # kein File angesprochen?
        return directory_namestring(pathname); # ja -> fertig
      var object namestring = whole_namestring(pathname);
      with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
        # Lock für dieses File holen:
        set_break_sem_4(); # Unterbrechungen währenddessen verhindern
        begin_system_call();
        var BPTR lock = Lock(namestring_asciz,ACCESS_READ);
        if (lock==BPTR_NULL) {
          if (!(IoErr()==ERROR_OBJECT_NOT_FOUND)) {
            end_system_call(); clr_break_sem_4(); OS_file_error(STACK_0);
          }
          end_system_call(); clr_break_sem_4();
          # File existiert nicht.
          filestatus = (struct FileInfoBlock *)NULL; return namestring;
        }
        end_system_call();
        # File existiert.
        # Information holen:
        var local LONGALIGNTYPE(struct FileInfoBlock) status;
        var struct FileInfoBlock * statusptr = LONGALIGN(&status);
        begin_system_call();
        if (! Examine(lock,statusptr) ) {
          UnLock(lock); end_system_call(); clr_break_sem_4(); OS_file_error(STACK_0);
        }
        UnLock(lock);
        end_system_call();
        clr_break_sem_4();
        if (statusptr->fib_DirEntryType >= 0) { # Ist es ein Directory?
          # STACK_0 = Wert für Slot PATHNAME von FILE-ERROR
          pushSTACK(whole_namestring(STACK_0));
          pushSTACK(TheSubr(subr_self)->name);
          fehler(file_error,
                 GETTEXT("~: ~ names a directory, not a file")
                );
        } else {
          # normales File
          pushSTACK(namestring);
          # Die Groß-/Kleinschreibung des Truename wird bestimmt durch
          # das bereits existierende File.
          pushSTACK(asciz_to_string(&statusptr->fib_FileName[0],O(pathname_encoding)));
          split_name_type(1);
          var object pathname = STACK_(0+3); # der kopierte Pathname
          ThePathname(pathname)->pathname_type = popSTACK();
          ThePathname(pathname)->pathname_name = popSTACK();
          # Fertig.
          filestatus = statusptr;
          return popSTACK(); # namestring
        }
      });
    }

# Dasselbe unter der Annahme, dass das Directory bereits existiert.
# (Keine Vereinfachung, da wir ja den Truename bestimmen müssen.??)
  global object assume_dir_exists (void);
  global object assume_dir_exists()
    {
      subr_self = L(open); return assure_dir_exists(true,false);
    }

#endif

#ifdef PATHNAME_UNIX

# UP: Liefert das aktuelle Directory.
# < ergebnis: aktuelles Directory (als Pathname)
# can trigger GC
  local object default_directory (void);
  local object default_directory()
    # Working Directory (von UNIX) ist das aktuelle Directory:
    {
      var char path_buffer[MAXPATHLEN]; # vgl. GETWD(3)
      # Working Directory in path_buffer ablegen:
      begin_system_call();
      if ( getwd(&path_buffer[0]) ==NULL) {
        end_system_call();
        pushSTACK(O(punkt_string)); # Wert für Slot PATHNAME von FILE-ERROR
        pushSTACK(asciz_to_string(&path_buffer[0],O(pathname_encoding))); # Meldung
        fehler(file_error,
               GETTEXT("UNIX error while GETWD: ~")
              );
      }
      end_system_call();
      # Es muss mit '/' anfangen:
      if (!(path_buffer[0] == '/')) {
        pushSTACK(O(punkt_string)); # Wert für Slot PATHNAME von FILE-ERROR
        pushSTACK(asciz_to_string(&path_buffer[0],O(pathname_encoding)));
        fehler(file_error,
               GETTEXT("UNIX GETWD returned ~")
              );
      }
      # in Pathname umwandeln:
      return asciz_dir_to_pathname(&path_buffer[0],O(pathname_encoding));
    }

# UP: Füllt Default-Directory in einen Pathname ein.
# use_default_dir(pathname)
# > pathname: nicht-Logical Pathname
# < ergebnis: neuer Pathname, bei dem Directory kein :RELATIVE enthält.
#             (kurz: "absoluter Pathname")
# can trigger GC
  local object use_default_dir (object pathname);
  local object use_default_dir(pathname)
    var object pathname;
    {
      # erst den Pathname kopieren:
      pathname = copy_pathname(pathname);
      # Dann das Default-Directory in den Pathname einbauen:
      {
        var object subdirs = ThePathname(pathname)->pathname_directory;
        # Fängt pathname-directory mit :RELATIVE an?
        if (eq(Car(subdirs),S(Krelative))) {
          # ja -> Ersetze :RELATIVE durch default-subdirs, d.h.
          # bilde  (append default-subdirs (cdr subdirs))
          #      = (nreconc (reverse default-subdirs) (cdr subdirs))
          pushSTACK(pathname);
          pushSTACK(Cdr(subdirs));
          var object temp = default_directory();
          temp = ThePathname(temp)->pathname_directory;
          temp = reverse(temp);
          subdirs = nreconc(temp,popSTACK());
          pathname = popSTACK();
          # in den Pathname eintragen:
          ThePathname(pathname)->pathname_directory = subdirs;
        }
      }
      return pathname;
    }

# UP: Stellt sicher, dass das Directory eines Pathname existiert, und löst
# dabei symbolische Links auf.
# assure_dir_exists(tolerantp)
# > STACK_0: nicht-Logical Pathname, bei dem Directory kein :RELATIVE enthält.
# > links_resolved: Flag, ob im Directory des Pathname schon alle Links
#     aufgelöst sind und es als existierend bekannt ist
# > tolerantp: Flag, ob ein Fehler vermieden werden soll
# > subr_self: Aufrufer (ein SUBR)
# < STACK_0: (evtl. derselbe) Pathname, wobei weder fürs Directory noch
#            für den Filenamen ein symbolisches Link zu verfolgen ist.
# < ergebnis:
#     falls Name=NIL: Directory-Namestring (für UNIX, mit '/' am Schluss)
#     falls Name/=NIL: Namestring (für UNIX)
#     falls tolerantp evtl.: nullobj
# < filestatus: Falls Name/=NIL: NULL falls das File nicht existiert,
#                                sonst ein Pointer auf eine STAT-Information.
# can trigger GC
  local var struct stat * filestatus;
  local object assure_dir_exists (bool links_resolved, bool tolerantp);
  #ifdef HAVE_LSTAT
    #define if_HAVE_LSTAT(statement)  statement
  #else
    #define if_HAVE_LSTAT(statement)
  #endif
  local object assure_dir_exists(links_resolved,tolerantp)
    var bool links_resolved;
    var bool tolerantp;
    {
      var uintC allowed_links = MAXSYMLINKS; # Anzahl der noch erlaubten symbolischen Links
      if (links_resolved)
        goto dir_exists;
      loop { # Schleife über die aufzulösenden symbolischen Links
        # Truepath des Directory bestimmen:
        {
          var char path_buffer[MAXPATHLEN]; # vgl. REALPATH(3)
          {
            var object pathname = STACK_0;
            var uintC stringcount = host_namestring_parts(pathname); # Strings für den Host
            stringcount += directory_namestring_parts(pathname); # Strings zum Directory
            pushSTACK(O(punkt_string)); # und "."
            var object string = string_concat(stringcount+1); # zusammenhängen
            # symbolische Links darin auflösen:
            with_sstring_0(string,O(pathname_encoding),string_asciz, {
              begin_system_call();
              if ( realpath(string_asciz,&path_buffer[0]) ==NULL) {
                if (!(errno==ENOENT)) { end_system_call(); OS_file_error(STACK_0); }
                end_system_call();
                if (!tolerantp)
                  fehler_dir_not_exists(asciz_dir_to_pathname(&path_buffer[0],O(pathname_encoding))); # fehlerhafte Komponente
                end_system_call();
                FREE_DYNAMIC_ARRAY(string_asciz);
                return nullobj;
              }
              end_system_call();
            });
          }
          # Neuer Directory-Path muss mit '/' anfangen:
          if (!(path_buffer[0] == '/')) {
            # STACK_0 = Wert für Slot PATHNAME von FILE-ERROR
            pushSTACK(asciz_to_string(&path_buffer[0],O(pathname_encoding)));
            fehler(file_error,
                   GETTEXT("UNIX REALPATH returned ~")
                  );
          }
          # Am Schluss evtl. ein '/' anfügen:
          var char* pathptr = &path_buffer[0];
          var uintL len = 0; # Stringlänge
          until (*pathptr == 0) { pathptr++; len++; } # ASCIZ-Stringende suchen
          if (!((len>0) && (pathptr[-1]=='/'))) {
            *pathptr = '/'; len++; # ein '/' anfügen
          }
          # und in einen String umwandeln:
          var object new_string = n_char_to_string(&path_buffer[0],len,O(pathname_encoding));
          # Pathname draus machen und dessen Directory verwenden:
          var object new_pathname = coerce_pathname(new_string);
          ThePathname(STACK_0)->pathname_directory
            = ThePathname(new_pathname)->pathname_directory;
        }
       dir_exists:
        # Information zum angesprochenen File holen:
        if (namenullp(STACK_0)) # kein File angesprochen?
          return directory_namestring(STACK_0); # ja -> fertig
        var object namestring = whole_namestring(STACK_0); # zusammenhängen
        # Information holen:
        var local struct stat status;
        with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
          begin_system_call();
          if (!( lstat(namestring_asciz,&status) ==0)) {
            if (!(errno==ENOENT)) { end_system_call(); OS_file_error(STACK_0); }
            # File existiert nicht.
            end_system_call();
            FREE_DYNAMIC_ARRAY(namestring_asciz);
            filestatus = (struct stat *)NULL; return namestring;
          }
          end_system_call();
          # File existiert.
          if (S_ISDIR(status.st_mode)) { # Ist es ein Directory?
            # STACK_0 = Wert für Slot PATHNAME von FILE-ERROR
            pushSTACK(whole_namestring(STACK_0));
            pushSTACK(TheSubr(subr_self)->name);
            fehler(file_error,
                   GETTEXT("~: ~ names a directory, not a file")
                  );
          }
          if_HAVE_LSTAT(
          elif (possible_symlink(namestring_asciz) && S_ISLNK(status.st_mode)) { # Ist es ein symbolisches Link?
            # ja -> weiterverfolgen:
            if (allowed_links==0) { # keine Links mehr erlaubt?
              # ja -> UNIX-Error ELOOP simulieren
              begin_system_call();
              errno = ELOOP_VALUE;
              end_system_call();
              OS_file_error(STACK_0);
            }
            allowed_links--; # danach ist ein Link weniger erlaubt
            var uintL linklen = status.st_size; # vermutliche Länge des Link-Inhalts
           retry_readlink:
            {
              var DYNAMIC_ARRAY(linkbuf,char,linklen+1); # Buffer für den Link-Inhalt
              # Link-Inhalt lesen:
              begin_system_call();
              {
                var int result = readlink(namestring_asciz,linkbuf,linklen);
                end_system_call();
                if (result<0)
                  OS_file_error(STACK_0);
                if (!(result == (int)linklen)) { # manchmal (AIX, NFS) stimmt status.st_size nicht
                  FREE_DYNAMIC_ARRAY(linkbuf); linklen = result; goto retry_readlink;
                }
              }
              # Daraus ein Pathname machen:
              # (MERGE-PATHNAMES (PARSE-NAMESTRING linkbuf) pathname-without-name&type)
              pushSTACK(subr_self);
              pushSTACK(n_char_to_string(linkbuf,linklen,O(pathname_encoding)));
              FREE_DYNAMIC_ARRAY(linkbuf);
            }
            funcall(L(parse_namestring),1);
            pushSTACK(value1);
            var object pathname = copy_pathname(STACK_(0+2));
            ThePathname(pathname)->pathname_name = NIL;
            ThePathname(pathname)->pathname_type = NIL;
            pushSTACK(pathname);
            funcall(L(merge_pathnames),2);
            subr_self = popSTACK();
            STACK_0 = value1;
          }
          ) # HAVE_LSTAT
          else {
            # normales File
            filestatus = &status; return namestring;
          }
        });
      }
    }

# Dasselbe unter der Annahme, dass das Directory bereits existiert.
# (Nur wenig Vereinfachung, da das File ein symbolisches Link in ein anderes
# Directory sein kann, und dieses muss dann als existent überprüft werden.)
  global object assume_dir_exists (void);
  global object assume_dir_exists()
    {
      subr_self = L(open); return assure_dir_exists(true,false);
    }

#endif

#ifdef PATHNAME_RISCOS

# Ein "absoluter Pathname" ist ein Pathname, bei dem Directory mit
# (:ABSOLUTE :ROOT ...) beginnt.

# UP: Liefert das aktuelle Directory.
# < ergebnis: aktuelles Directory (als Pathname)
# can trigger GC
  local object default_directory (void);
  local object default_directory()
    # Working Directory (von RISCOS) ist das aufgelöste "@":
    {
      var char path_buffer[MAXPATHLEN];
      # Working Directory in path_buffer ablegen:
      begin_system_call();
      if ( realpath("@",&path_buffer[0]) ==NULL) { OS_error(); }
      end_system_call();
      # in Pathname umwandeln:
      return asciz_dir_to_pathname(&path_buffer[0],O(pathname_encoding));
    }

#if 0 # unbenutzt
# UP: Convert a valid RISCOS file namestring to an absolute pathname.
# canonicalise_filename(filename)
# > filename: Simple-Asciz-String
# < result: absolute pathname
  local object canonicalise_filename (object filename);
  local object canonicalise_filename(filename)
    var object filename;
    {
      var char path_buffer[MAXPATHLEN];
      with_string_0(filename,O(pathname_encoding),filename_asciz, {
        begin_system_call();
        if ( realpath(filename_asciz,&path_buffer[0]) ==NULL) { OS_error(); }
        end_system_call();
      });
      # in Pathname umwandeln:
      return coerce_pathname(asciz_to_string(&path_buffer[0],O(pathname_encoding)));
    }
#endif

# UP: Convert a valid RISCOS directory namestring to an absolute pathname.
# canonicalise_dirname(pathname,dirname)
# > pathname: Pathname whose host name and device is to be used
# > dirname: Normal-Simple-String, ends with '.'
# < result: absolute pathname
  local object canonicalise_dirname (object pathname, object dirname);
  local object canonicalise_dirname(pathname,dirname)
    var object pathname;
    var object dirname;
    {
      pushSTACK(pathname);
      var uintC stringcount = host_namestring_parts(pathname); # Strings für den Host
      # Device, vgl. directory_namestring_parts():
      {
        var object device = ThePathname(pathname)->pathname_device;
        if (!(nullp(device))) { # NIL -> kein String
          pushSTACK(O(doppelpunkt_string)); # ":"
          pushSTACK(device); # Device auf den Stack
          pushSTACK(O(punkt_string)); # "."
          stringcount += 3; # und mitzählen
        }
      }
      pushSTACK(dirname);
      var object dir_string = string_concat(stringcount+1);
      with_sstring(dir_string,O(pathname_encoding),dir_path,len, {
        # Punkt am Schluss durch Nullbyte ersetzen:
        ASSERT((len > 0) && (dir_path[len-1] == '.'));
        dir_path[len-1] = '\0';
        # absolut machen:
        var char path_buffer[MAXPATHLEN];
        begin_system_call();
        if ( realpath(dir_path,&path_buffer[0]) ==NULL) {
          end_system_call(); OS_file_error(STACK_0);
        }
        end_system_call();
        skipSTACK(1);
        # in Pathname umwandeln:
        dir_string = asciz_dir_to_pathname(&path_buffer[0],O(pathname_encoding));
      });
      return dir_string;
    }

# UP: Füllt Default-Directory in einen Pathname ein.
# use_default_dir(pathname)
# > pathname: nicht-Logical Pathname
# < ergebnis: neuer Pathname, bei dem Directory kein :RELATIVE u.ä. enthält.
#             (kurz: "absoluter Pathname")
# can trigger GC
  local object use_default_dir (object pathname);
  local object use_default_dir(pathname)
    var object pathname;
    {
      var bool resolved_root = false;
     retry:
      # erst den Pathname kopieren:
      pathname = copy_pathname(pathname);
      {
        var object subdirs = ThePathname(pathname)->pathname_directory;
        # Ist das Device angegeben, so muss das Directory mit (:ABSOLUTE :ROOT ...)
        # anfangen (oder mit (:RELATIVE ...) - das wird ersetzt).
        if (!nullp(ThePathname(pathname)->pathname_device)) {
          if (eq(Car(subdirs),S(Krelative))) {
            pushSTACK(pathname); # pathname retten
            pushSTACK(allocate_cons());
            var object new_cons = allocate_cons();
            subdirs = popSTACK();
            pathname = popSTACK(); # pathname zurück
            Car(subdirs) = S(Kabsolute); Cdr(subdirs) = new_cons;
            Car(new_cons) = S(Kroot); Cdr(new_cons) = Cdr(ThePathname(pathname)->pathname_directory);
            ThePathname(pathname)->pathname_directory = subdirs;
          } elif (!(eq(Car(subdirs),S(Kabsolute)) && eq(Car(Cdr(subdirs)),S(Kroot)))) {
            pushSTACK(pathname); # Wert für Slot PATHNAME von FILE-ERROR
            pushSTACK(pathname);
            pushSTACK(O(root_string));
            pushSTACK(TheSubr(subr_self)->name);
            fehler(file_error,
                   GETTEXT("~: If a device is specified, the directory must begin with ~: ~")
                  );
          }
        }
        pushSTACK(pathname); # pathname retten
        var object defaults;
        if (eq(Car(subdirs),S(Krelative))) {
          pushSTACK(Cdr(subdirs)); defaults = default_directory();
        } else { # (eq(Car(subdirs),S(Kabsolute)))
          var object next = Car(Cdr(subdirs));
          pushSTACK(Cdr(Cdr(subdirs)));
          if (eq(next,S(Kroot))) { # :ROOT -> "$." auflösen oder fertig
            # "$." wird nur dann aufgelöst, wenn Host oder Device noch
            # unbekannt sind, aber nur einmal (um eine Endlosschleife zu
            # verhindern). Ob Host oder Device =NIL sind, ist nämlich
            # nicht so wichtig.
            if (!resolved_root
                && (nullp(ThePathname(pathname)->pathname_host)
                    || nullp(ThePathname(pathname)->pathname_device)
               )   ) {
              defaults = canonicalise_dirname(pathname,O(root_string));
              resolved_root = true;
            } else
              goto resolved;
          } elif (eq(next,S(Khome))) { # :HOME -> "&." auflösen
            defaults = canonicalise_dirname(pathname,O(home_string));
          } elif (eq(next,S(Kcurrent))) { # :CURRENT -> "@." auflösen
            defaults = canonicalise_dirname(pathname,O(current_string));
          } elif (eq(next,S(Klibrary))) { # :LIBRARY -> "%." auflösen
            defaults = canonicalise_dirname(pathname,O(library_string));
          } elif (eq(next,S(Kprevious))) { # :PREVIOUS -> "\\." auflösen
            defaults = canonicalise_dirname(pathname,O(previous_string));
          } else {
            NOTREACHED
          }
        }
        # Stackaufbau: pathname, rest-subdirs.
        # Nicht ganz so wie bei MERGE-PATHNAMES verfahren:
        # bilde  (append default-subdirs rest-subdirs)
        #      = (nreconc (reverse default-subdirs) rest-subdirs)
        pathname = STACK_1;
        ThePathname(pathname)->pathname_host = ThePathname(defaults)->pathname_host;
        ThePathname(pathname)->pathname_device = ThePathname(defaults)->pathname_device;
        defaults = ThePathname(defaults)->pathname_directory;
        defaults = reverse(defaults); subdirs = nreconc(defaults,popSTACK());
        pathname = popSTACK();
        ThePathname(pathname)->pathname_directory = subdirs;
        # Es könnte sein, dass auch jetzt noch nicht alles aufgelöst ist.
        goto retry;
      }
     resolved: # Stackaufbau: pathname, subdir-oldlist.
      # Liste durchgehen und dabei neu aufconsen, dabei "^." verarbeiten.
      # (Sonst müsste dies assure_dir_exists() machen.)
      pushSTACK(S(Kroot)); pushSTACK(S(Kabsolute));
      { var object newlist = listof(2); pushSTACK(newlist); }
      # Stackaufbau: pathname, subdir-oldlist, subdir-newlist.
      while (mconsp(STACK_1)) { # Bis oldlist am Ende ist:
        var object subdir = Car(STACK_1); # nächstes subdir
        if (eq(subdir,S(Kparent))) {
          # = :PARENT -> newlist um eins verkürzen:
          if (matomp(Cdr(Cdr(STACK_0)))) { # newlist (bis auf :ABSOLUTE und :ROOT) leer ?
            # :PARENT von "$." aus liefert Error
            pushSTACK(STACK_2); # Wert für Slot PATHNAME von FILE-ERROR
            pushSTACK(O(root_string)); # "$."
            pushSTACK(directory_namestring(STACK_(2+2))); # Directory von pathname
            fehler(file_error,
                   GETTEXT("no directory ~ above ~")
                  );
          }
          STACK_0 = Cdr(STACK_0);
        } else {
          # newlist um eins verlängern:
          pushSTACK(subdir);
          var object new_cons = allocate_cons();
          Car(new_cons) = popSTACK();
          Cdr(new_cons) = STACK_0;
          STACK_0 = new_cons;
        }
        STACK_1 = Cdr(STACK_1);
      }
      var object subdirs = nreverse(popSTACK()); # newlist, wieder umdrehen
      skipSTACK(1);
      pathname = popSTACK();
      ThePathname(pathname)->pathname_directory = subdirs; # in den Pathname eintragen
      return pathname;
    }

# UP: Liefert den Namestring eines Pathname fürs Betriebssystem.
# OSnamestring(dir_namestring)
# > STACK_0: nicht-Logical Pathname
# > dir_namestring: Directory-Namestring
# < ergebnis: Namestring (für RISCOS, mit Name/Type vertauscht)
# can trigger GC
  local object OSnamestring (object dir_namestring);
  local object OSnamestring(dir_namestring)
    var object dir_namestring;
    {
      var object pathname = STACK_0;
      var uintC stringcount;
      pushSTACK(dir_namestring); # Directory-Namestring als 1. String
      stringcount = # und Strings zum Filenamen
        (nullp(ThePathname(pathname)->pathname_type)
         ? nametype_namestring_parts(ThePathname(pathname)->pathname_name,
                                     ThePathname(pathname)->pathname_type,
                                     ThePathname(pathname)->pathname_version)
         # Name und Typ vertauschen (der Typ wird zu einem Subdirectory-Namen):
         : nametype_namestring_parts(ThePathname(pathname)->pathname_type,
                                     ThePathname(pathname)->pathname_name,
                                     ThePathname(pathname)->pathname_version)
        );
      return string_concat(1+stringcount); # zusammenhängen
    }

# UP: Stellt sicher, dass das Directory eines Pathname existiert.
# Sonst Fehlermeldung.
# assure_dir_exists(links_resolved,tolerantp)
# assure_dir_exists_(links_resolved,tolerantp,allowdir)
# > STACK_0: absoluter Pathname ohne Wildcards im Directory
# > links_resolved: Flag, ob im Directory des Pathname schon alle Links
#     aufgelöst sind und es als existierend bekannt ist
# > tolerantp: Flag, ob ein Fehler vermieden werden soll
# > allowdir: Flag, ob bei Name/=NIL ein Directory statt eines File erlaubt ist
# < ergebnis:
#     falls Name=NIL: Directory-Namestring (für RISCOS, mit '.' am Schluss)
#     falls Name/=NIL: Namestring (für RISCOS)
#     falls tolerantp evtl.: nullobj
# < filestatus: Falls Name/=NIL: NULL falls das File nicht existiert,
#                                sonst ein Pointer auf eine STAT-Information.
# can trigger GC
  local var struct stat * filestatus;
  #define assure_dir_exists(links_resolved,tolerantp)  \
     assure_dir_exists_(links_resolved,tolerantp,false)
  local object assure_dir_exists_ (bool links_resolved, bool tolerantp, bool allowdir);
  local object assure_dir_exists_(links_resolved,tolerantp,allowdir)
    var bool links_resolved;
    var bool tolerantp;
    var bool allowdir;
    {
      var object dir_namestring = directory_namestring(STACK_0);
      if (!links_resolved) {
        # Existenztest:
        var struct stat statbuf;
        with_sstring(dir_namestring,O(pathname_encoding),dir_namestring_asciz,len, {
          ASSERT((len > 0) && (dir_namestring_asciz[len-1]=='.'));
          dir_namestring_asciz[len-1] = '\0'; # '.' am Schluss durch Nullbyte ersetzen
          begin_system_call();
          if (stat(dir_namestring_asciz,&statbuf) < 0) {
            if (!(tolerantp && (errno==ENOENT))) {
              end_system_call(); OS_file_error(STACK_0);
            }
            end_system_call();
            FREE_DYNAMIC_ARRAY(dir_namestring_asciz);
            return nullobj;
          }
          end_system_call();
        });
        if (!S_ISDIR(statbuf.st_mode)) { # gefundene Datei kein Unterdirectory ?
          if (tolerantp) return nullobj;
          fehler_dir_not_exists(dir_namestring);
        }
      }
      # Information zum angesprochenen File holen:
      if (namenullp(STACK_0)) { # kein File angesprochen?
        return dir_namestring; # ja -> fertig
      } else {
        var object namestring = OSnamestring(dir_namestring);
        # Information holen:
        var local struct stat status;
        with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
          begin_system_call();
          if (stat(namestring_asciz,&status) < 0) {
            if (!(errno==ENOENT)) { end_system_call(); OS_file_error(STACK_0); }
            # File existiert nicht.
            end_system_call();
            FREE_DYNAMIC_ARRAY(namestring_asciz);
            filestatus = (struct stat *)NULL; return namestring;
          }
          end_system_call();
        });
        # File existiert.
        if (!allowdir && S_ISDIR(status.st_mode)) { # Ist es ein Directory?
          # STACK_0 = Wert für Slot PATHNAME von FILE-ERROR
          pushSTACK(whole_namestring(STACK_0));
          pushSTACK(TheSubr(subr_self)->name);
          fehler(file_error,
                 GETTEXT("~: ~ names a directory, not a file")
                );
        } else {
          # normales File oder (erlaubterweise) Directory
          filestatus = &status; return namestring;
        }
      }
    }

# Dasselbe unter der Annahme, dass das Directory bereits existiert.
# (Keine Vereinfachung, da wir ja den Truename bestimmen müssen.??)
  global object assume_dir_exists (void);
  global object assume_dir_exists()
    {
      subr_self = L(open); return assure_dir_exists(true,false);
    }

# Ein File "name.type" wird dem RISCOS als "type.name" vermittelt, dabei ist
# "type" der Name eines Unterverzeichnisses! Soll ein File "name.type" angelegt
# werden, muss daher zuerst das Unterverzeichnis "type" erzeugt werden.
# prepare_create(pathname);
# > pathname: ein Pathname
# can trigger GC
  local void prepare_create (object pathname);
  local object pathname_add_subdir (void);
  local void prepare_create(pathname)
    var object pathname;
    {
      if (!nullp(ThePathname(pathname)->pathname_type)) {
        # call pathname_add_subdir:
        pushSTACK(pathname); pushSTACK(ThePathname(pathname)->pathname_type);
        pathname = pathname_add_subdir();
        ThePathname(pathname)->pathname_name = NIL;
        ThePathname(pathname)->pathname_type = NIL;
        # call MAKE-DIR if the directory does not exist:
        pushSTACK(subr_self); # subr_self retten
        pushSTACK(pathname);
        if (eq(assure_dir_exists(false,true),nullobj)) {
          funcall(L(make_dir),1);
        } else {
          skipSTACK(1);
        }
        subr_self = popSTACK(); # subr_self zurück
      }
    }

#else

# Normally nothing special to do before creating a file.
  #define prepare_create(pathname)

#endif

#if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
#if 0 # unbenutzt
# UP: Macht aus einem Directory-Namestring einen, der für DOS geeignet ist.
# OSdirnamestring(namestring)
# > namestring: neu erzeugter Directory-Namestring, mit '\' am Schluss,
#               ein Normal-Simple-String
# < ergebnis: Namestring zu diesem Directory, im DOS-Format: letzter '\'
#             gestrichen, falls überflüssig, ein Normal-Simple-String
# can trigger GC
  local object OSdirnamestring (object namestring);
  local object OSdirnamestring(namestring)
    var object namestring;
    {
      var uintL len = Sstring_length(namestring);
      if (len==0) goto ok; # Leerstring -> nichts streichen
      var chart ch = TheSstring(namestring)->data[len-1];
      if (!chareq(ch,ascii('\\'))) goto ok; # kein '\' am Schluss -> nichts streichen
      if (len==1) goto ok; # "\" bedeutet Root -> nicht streichen
      ch = TheSstring(namestring)->data[len-2];
      if (chareq(ch,ascii('\\')) || chareq(ch,ascii(':'))) # davor ein '\' oder ':'
        goto ok; # -> bedeutet Parent -> nicht streichen
      # '\' am Schluss streichen:
        namestring = subsstring(namestring,0,len-1);
     ok: # nichts streichen
      return namestring;
    }
#endif
# UP: Setzt das Default-Drive und sein Default-Directory neu.
# change_default();
# > STACK_0: absoluter Pathname, bei dem Device ein String ist und Directory
#     kein :RELATIVE, :CURRENT, :PARENT enthält, und Name und Typ =NIL sind.
# can trigger GC
  local void change_default (void);
  local void change_default()
    {
      # Default-Directory zu diesem Drive neu setzen:
      {
        var object pathname = STACK_0;
        var uintC stringcount =
          directory_namestring_parts(pathname); # Strings fürs Directory
        # ohne überflüssiges '\' am Schluss
        if (mconsp(Cdr(ThePathname(pathname)->pathname_directory))) {
          skipSTACK(1); stringcount--;
        }
        var object string = string_concat(stringcount); # zusammenhängen
        with_sstring_0(string,O(pathname_encoding),asciz, {
          # Default-Directory ändern:
          change_current_directory(asciz);
        });
      }
      # Default-Drive neu setzen:
      O(default_drive) = ThePathname(STACK_0)->pathname_device;
      # *DEFAULT-PATHNAME-DEFAULTS* neu setzen:
      recalc_defaults_pathname();
    }
#endif
#ifdef PATHNAME_AMIGAOS
# UP: Setzt das Default-Directory neu.
# change_default();
# > STACK_0: absoluter Pathname, bei dem Directory kein :RELATIVE, :CURRENT,
#     :PARENT enthält, und Name und Typ =NIL sind.
# can trigger GC
  local void change_default (void);
  extern BPTR orig_dir_lock; # Lock auf das ursprüngliche Verzeichnis
                             # (das gehört nicht uns, nicht freigeben!)
  local void change_default()
    {
      var object dir_namestring = directory_namestring(STACK_0);
      dir_namestring = OSdirnamestring(dir_namestring); # ohne überflüssigen '/' am Schluss
      with_sstring_0(dir_namestring,O(pathname_encoding),dir_namestring_asciz, {
        # Default-Directory ändern:
        set_break_sem_4();
        begin_system_call();
        var BPTR lock = Lock(dir_namestring_asciz,ACCESS_READ);
        if (lock==BPTR_NULL) { end_system_call(); OS_file_error(STACK_0); }
        lock = CurrentDir(lock); # current directory neu setzen
        # Lock zum alten current directory merken bzw. aufgeben:
        if (orig_dir_lock == BPTR_NONE)
          orig_dir_lock = lock;
        else
          UnLock(lock);
        end_system_call();
        clr_break_sem_4();
      });
    }
#endif
#ifdef PATHNAME_UNIX
# UP: Setzt das Default-Directory neu.
# change_default();
# > STACK_0: absoluter Pathname, bei dem Directory kein :RELATIVE, :CURRENT,
#     :PARENT enthält, und Name und Typ =NIL sind.
# can trigger GC
  local void change_default (void);
  local void change_default()
    {
      var object string = directory_namestring(STACK_0);
      with_sstring_0(string,O(pathname_encoding),asciz, {
        # Default-Directory ändern:
        begin_system_call();
        if (!( chdir(asciz) ==0)) { end_system_call(); OS_file_error(STACK_0); }
        end_system_call();
      });
    }
#endif
#ifdef PATHNAME_RISCOS
# UP: Setzt das Default-Directory neu.
# change_default();
# > STACK_0: absoluter Pathname, bei dem Name und Typ =NIL sind.
# can trigger GC
  local void change_default (void);
  local void change_default()
    {
      var object dir_namestring = directory_namestring(STACK_0);
      with_sstring(dir_namestring,O(pathname_encoding),dir_namestring_asciz,len, {
        ASSERT((len > 0) && (dir_namestring_asciz[len-1]=='.'));
        dir_namestring_asciz[len-1] = '\0'; # '.' am Schluss durch Nullbyte ersetzen
        begin_system_call();
        if (!( chdir(dir_namestring_asciz) ==0)) { end_system_call(); OS_file_error(STACK_0); }
        end_system_call();
      });
    }
#endif

LISPFUN(namestring,1,1,norest,nokey,0,NIL)
# (NAMESTRING pathname), CLTL S. 417
# (NAMESTRING pathname t) -> Namestring im externen Format
#   Unix: mit Default-Directory
  {
    var object flag = popSTACK(); # optionales Argument flag
    var object pathname = coerce_pathname(popSTACK()); # Argument zu einem Pathname machen
    #if defined(PATHNAME_UNIX) || defined(PATHNAME_AMIGAOS) || defined(PATHNAME_RISCOS) || defined(PATHNAME_WIN32)
    if (!eq(flag,unbound) && !nullp(flag)) {
      # flag /= NIL -> fürs Betriebssystem:
      check_no_wildcards(pathname); # mit Wildcards -> Fehler
      pathname = use_default_dir(pathname); # Default-Directory einfügen
      # (da Unix/AMIGAOS das Default-Directory von LISP nicht kennt
      # und Win32 multitasking ist)
    }
    #endif
    subr_self = L(namestring); # ("aktuelles" SUBR für Fehlermeldung)
    value1 = whole_namestring(pathname);
    mv_count=1;
  }

# Fehlermeldung wegen fehlendem Dateinamen
# fehler_noname(pathname);
# > pathname: Pathname
  nonreturning_function(local, fehler_noname, (object pathname));
  local void fehler_noname(pathname)
    var object pathname;
    {
      pushSTACK(pathname); # Wert für Slot PATHNAME von FILE-ERROR
      pushSTACK(pathname);
      fehler(file_error,
             GETTEXT("no file name given: ~")
            );
    }

# Fehler wegen unzulässiger Name/Type-Angabe
# fehler_notdir(pathname);
# > pathname: Pathname
  nonreturning_function(local, fehler_notdir, (object pathname));
  local void fehler_notdir(pathname)
    var object pathname;
    {
      pushSTACK(pathname); # Wert für Slot PATHNAME von FILE-ERROR
      pushSTACK(pathname);
      fehler(file_error,
             GETTEXT("not a directory: ~")
            );
    }

# Test, ob ein File existiert:
# file_exists(namestring)
# > vorausgegangen: assure_dir_exists()
# > STACK_0: Pathname, wie nach Ausführung von assure_dir_exists(), Name/=NIL
# > namestring: dessen Namestring fürs Betriebssystem
  #if defined(MSDOS) || defined(WIN32_NATIVE)
    #ifdef MSDOS
      local inline int access0 (CONST char* path);
      local inline int access0(path)
        var CONST char* path;
        {
          begin_system_call();
          var int erg = access(path,0);
          end_system_call();
          return erg;
        }
    #endif
    #ifdef WIN32_NATIVE
      local inline int access0 (const char* path);
      local inline int access0(path)
        var const char* path;
        {
          begin_system_call();
          var DWORD fileattr = GetFileAttributes(path);
          if (fileattr == 0xFFFFFFFF) {
            if (GetLastError()==ERROR_FILE_NOT_FOUND) {
              end_system_call(); return -1;
            }
            end_system_call(); OS_file_error(STACK_0);
          }
          end_system_call();
          return 0;
        }
    #endif
    local bool file_exists (object namestring);
    local bool file_exists(namestring)
      var object namestring;
      {
        var bool exists;
        with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
          exists = (access0(namestring_asciz)==0);
        });
        return exists;
      }
  #endif
  #ifdef AMIGAOS
    #define file_exists(namestring)  (!(filestatus == (struct FileInfoBlock *)NULL))
    #define FILE_EXISTS_TRIVIAL
  #endif
  #if defined(UNIX) || defined(RISCOS)
    #define file_exists(namestring)  (!(filestatus == (struct stat *)NULL))
    #define FILE_EXISTS_TRIVIAL
  #endif

# Fehlermeldung wegen nicht existenter Datei
# fehler_file_not_exists();
# > STACK_0: Pathname
# > subr_self: Aufrufer (ein SUBR)
  nonreturning_function(local, fehler_file_not_exists, (void));
  local void fehler_file_not_exists()
    {
      # STACK_0 = Wert für Slot PATHNAME von FILE-ERROR
      pushSTACK(STACK_0); # pathname
      pushSTACK(TheSubr(subr_self)->name);
      fehler(file_error,
             GETTEXT("~: file ~ does not exist")
            );
    }

LISPFUNN(truename,1)
# (TRUENAME pathname), CLTL S. 413
  {
    var object pathname = popSTACK(); # pathname-Argument
    if (builtin_stream_p(pathname)) {
      # Stream -> extra behandeln:
      # muss File-Stream sein:
      pathname = as_file_stream(pathname);
      test_file_stream_named(pathname);
      # Streamtyp File-Stream
      value1 = TheStream(pathname)->strm_file_truename;
    } else {
      pathname = coerce_pathname(pathname); # zu einem Pathname machen
      check_no_wildcards(pathname); # mit Wildcards -> Fehler
      pathname = use_default_dir(pathname); # Default-Directory einfügen
      pushSTACK(pathname);
      # Directory muss existieren:
      var object namestring = assure_dir_exists(false,false); # Filename fürs Betriebssystem
      if (namenullp(STACK_0)) {
        # Kein Name angegeben
        if (!nullp(ThePathname(STACK_0)->pathname_type)) {
          # STACK_0 = Wert für Slot PATHNAME von FILE-ERROR
          pushSTACK(STACK_0); # pathname
          pushSTACK(TheSubr(subr_self)->name);
          fehler(file_error,
                 GETTEXT("~: pathname with type but without name makes no sense: ~")
                );
        }
        # Kein Name und kein Typ angegeben -> pathname als Ergebnis
      } else {
        # Name angegeben.
        # Überprüfe, ob die Datei existiert:
        if (!file_exists(namestring)) { fehler_file_not_exists(); }
        # Datei existiert -> Pathname als Wert
      }
      value1 = popSTACK();
    }
    mv_count=1;
  }

LISPFUNN(probe_file,1)
# (PROBE-FILE filename), CLTL S. 424
  {
    var object pathname = popSTACK(); # pathname-Argument
    if (builtin_stream_p(pathname)) {
      # Stream -> extra behandeln:
      # muss File-Stream sein:
      pathname = as_file_stream(pathname);
      test_file_stream_named(pathname);
      # Streamtyp File-Stream -> Truename nehmen:
      var uintB flags = TheStream(pathname)->strmflags;
      pathname = TheStream(pathname)->strm_file_truename;
      if (flags & strmflags_open_B) { # Datei geöffnet ?
        # ja -> Truename sofort als Ergebnis:
        value1 = pathname; mv_count=1; return;
      }
      # nein -> noch testen, ob die Datei zum Truename existiert.
    } else {
      pathname = coerce_pathname(pathname); # zu einem Pathname machen
    }
    # pathname ist jetzt ein Pathname.
    check_no_wildcards(pathname); # mit Wildcards -> Fehler
    pathname = use_default_dir(pathname); # Default-Directory einfügen
    if (namenullp(pathname)) { fehler_noname(pathname); } # Kein Name angegeben -> Fehler
    # Name angegeben.
    pushSTACK(pathname);
    # Directory muss existieren:
    var object namestring = assure_dir_exists(false,true); # Filename fürs Betriebssystem
    if (eq(namestring,nullobj)) {
      # Pfad zur Datei existiert nicht -> NIL als Wert:
      skipSTACK(1); value1 = NIL; mv_count=1; return;
    }
    # Überprüfe, ob die Datei existiert:
    if (file_exists(namestring)) {
      value1 = popSTACK(); mv_count=1; # Datei existiert -> Pathname als Wert
    } else {
      skipSTACK(1); value1 = NIL; mv_count=1; return; # sonst NIL als Wert
    }
  }

# Stellt fest, ob ein Directory existiert.
# directory_exists(pathname)
# > pathname: ein absoluter Pathname ohne Wildcards, mit Name=NIL und Typ=NIL
# < result: true wenn es ein existierendes Verzeichnis bezeichnet
# can trigger GC
  local bool directory_exists (object pathname);
  local bool directory_exists(pathname)
    var object pathname;
    {
      pushSTACK(pathname); # Pathname retten
      var object dir_namestring = directory_namestring(pathname);
      # Existenztest, siehe auch assure_dir_exists():
      var bool exists = true;
      #ifdef MSDOS
        if (!(nullp(Cdr(ThePathname(STACK_0)->pathname_directory))
              #ifdef PATHNAME_OS2
              || equal(Cdr(ThePathname(STACK_0)->pathname_directory),O(pipe_subdirs))
              #endif
           ) ) {
          with_sstring(dir_namestring,O(pathname_encoding),dir_namestring_asciz,len, {
            ASSERT((len > 0) && (dir_namestring_asciz[len-1] == '\\'));
            dir_namestring_asciz[len-1] = '\0'; # '\' am Schluss durch Nullbyte ersetzen
            var struct stat statbuf;
            begin_system_call();
            if (stat(dir_namestring_asciz,&statbuf) < 0) {
              if (!(errno==ENOENT)) { end_system_call(); OS_file_error(STACK_0); }
              exists = false;
            } else {
              if (!S_ISDIR(statbuf.st_mode)) # gefundene Datei kein Unterdirectory ?
                exists = false;
            }
            end_system_call();
          });
        }
      #endif
      #ifdef WIN32_NATIVE
        with_sstring_0(dir_namestring,O(pathname_encoding),dir_namestring_asciz, {
          if (!nullp(Cdr(ThePathname(STACK_0)->pathname_directory))) {
            var uintL len = Sstring_length(dir_namestring);
            ASSERT((len > 0) && (dir_namestring_asciz[len-1] == '\\'));
            dir_namestring_asciz[len-1] = '\0'; # '\' am Schluss durch Nullbyte ersetzen
          }
          begin_system_call();
          var DWORD fileattr = GetFileAttributes(dir_namestring_asciz);
          if (fileattr == 0xFFFFFFFF) {
            if (!(GetLastError()==ERROR_FILE_NOT_FOUND || GetLastError()==ERROR_PATH_NOT_FOUND || GetLastError()==ERROR_BAD_NETPATH)) {
              end_system_call(); OS_file_error(STACK_0);
            }
            exists = false;
          } else {
            if (!(fileattr & FILE_ATTRIBUTE_DIRECTORY)) # gefundene Datei kein Unterdirectory ?
              exists = false;
          }
          end_system_call();
        });
      #endif
      #ifdef PATHNAME_AMIGAOS
        dir_namestring = OSdirnamestring(dir_namestring); # ohne überflüssigen '/' am Schluss
        with_sstring_0(dir_namestring,O(pathname_encoding),dir_namestring_asciz, {
          # Lock für dieses Directory holen:
          set_break_sem_4(); # Unterbrechungen währenddessen verhindern
          begin_system_call();
          var BPTR lock = Lock(dir_namestring_asciz,ACCESS_READ);
          if (lock==BPTR_NULL) {
            var LONG errcode = IoErr();
            switch (errcode) {
              case ERROR_OBJECT_NOT_FOUND:
              case ERROR_ACTION_NOT_KNOWN:
                exists = false;
                break;
              default:
                end_system_call(); OS_file_error(STACK_0);
            }
          } else {
            var LONGALIGNTYPE(struct FileInfoBlock) fib;
            var struct FileInfoBlock * fibptr = LONGALIGN(&fib);
            var LONG ergebnis = Examine(lock,fibptr);
            if (!ergebnis || !(fibptr->fib_DirEntryType >= 0))
              exists = false;
            UnLock(lock);
          }
          end_system_call();
          clr_break_sem_4();
        });
      #endif
      #ifdef PATHNAME_UNIX
        pushSTACK(dir_namestring);
        pushSTACK(O(punkt_string)); # und "."
        dir_namestring = string_concat(2); # zusammenhängen
        with_sstring_0(dir_namestring,O(pathname_encoding),dir_namestring_asciz, {
          var struct stat statbuf;
          begin_system_call();
          if (stat(dir_namestring_asciz,&statbuf) < 0) {
            if (!(errno==ENOENT)) { end_system_call(); OS_file_error(STACK_0); }
            exists = false;
          } else {
            if (!S_ISDIR(statbuf.st_mode)) # gefundene Datei kein Unterdirectory ?
              exists = false;
          }
          end_system_call();
        });
      #endif
      #ifdef PATHNAME_RISCOS
        with_sstring(dir_namestring,O(pathname_encoding),dir_namestring_asciz,len, {
          ASSERT((len > 0) && (dir_namestring_asciz[len-1]=='.'));
          dir_namestring_asciz[len-1] = '\0'; # '.' am Schluss durch Nullbyte ersetzen
          var struct stat statbuf;
          begin_system_call();
          if (stat(dir_namestring_asciz,&statbuf) < 0) {
            if (!(errno==ENOENT)) { end_system_call(); OS_file_error(STACK_0); }
            exists = false;
          } else {
            if (!S_ISDIR(statbuf.st_mode)) # gefundene Datei kein Unterdirectory ?
              exists = false;
          }
          end_system_call();
        });
      #endif
      skipSTACK(1);
      return exists;
    }

LISPFUNN(probe_directory,1)
# (PROBE-DIRECTORY filename) stellt fest, ob ein Directory existiert.
  {
    var object pathname = popSTACK(); # pathname-Argument
    pathname = coerce_pathname(pathname); # zu einem Pathname machen
    check_no_wildcards(pathname); # mit Wildcards -> Fehler
    pathname = use_default_dir(pathname); # Default-Directory einfügen
    # Überprüfe, ob Name=NIL und Typ=NIL :
    if (!(nullp(ThePathname(pathname)->pathname_name)
          && nullp(ThePathname(pathname)->pathname_type)
       ) )
      fehler_notdir(pathname);
    value1 = (directory_exists(pathname) ? T : NIL); mv_count=1;
  }

# UP: Stellt fest, ob eine Datei geöffnet ist.
# openp(pathname)
#if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
# > pathname: absoluter Pathname, ohne Wildcards.
#endif
#ifdef PATHNAME_AMIGAOS
# > pathname: absoluter Pathname, ohne Wildcards, ohne :PARENT
#endif
#ifdef PATHNAME_UNIX
# > pathname: absoluter Pathname, ohne Wildcards, nach Auflösung
#             symbolischer Links
#endif
# < ergebnis: true, falls ein geöffneter File-Stream auf diese Datei existiert.
  local bool openp (object pathname);
  local bool openp(pathname)
    var object pathname;
    {
      var object flist = O(open_files); # Liste aller offenen Files durchlaufen
      while (consp(flist)) {
        var object f = Car(flist); # nächster offener Stream
        if (TheStream(f)->strmtype == strmtype_file) { # File-Stream ?
          if (equal(TheStream(f)->strm_file_truename,pathname))
            return true;
        }
        flist = Cdr(flist);
      }
      return false;
    }

# Fehlermeldung wegen Löschversuch auf geöffnete Datei
# fehler_delete_open(pathname);
# > pathname: Truename der Datei
  nonreturning_function(local, fehler_delete_open, (object pathname));
  local void fehler_delete_open(pathname)
    var object pathname;
    {
      pushSTACK(pathname); # Wert für Slot PATHNAME von FILE-ERROR
      pushSTACK(pathname);
      fehler(file_error,
             GETTEXT("cannot delete file ~ since there is file stream open to it")
            );
    }

LISPFUNN(delete_file,1)
# (DELETE-FILE filename), CLTL S. 424
  {
    var object pathname = popSTACK(); # pathname-Argument
    if (builtin_stream_p(pathname)) {
      # Stream -> extra behandeln:
      var object stream = as_file_stream(pathname); # muss File-Stream sein
      test_file_stream_named(stream);
      # Streamtyp File-Stream.
      # Falls Datei geöffnet, erst Datei schließen:
      if (TheStream(stream)->strmflags & strmflags_open_B) { # Datei geöffnet ?
        pushSTACK(stream); builtin_stream_close(&STACK_0); stream = popSTACK();
      }
      # Dann den Truename als zu löschende Datei nehmen:
      pathname = TheStream(stream)->strm_file_truename;
    } else {
      pathname = coerce_pathname(pathname); # zu einem Pathname machen
    }
    # pathname ist jetzt ein Pathname.
    check_no_wildcards(pathname); # mit Wildcards -> Fehler
    pathname = use_default_dir(pathname); # Default-Directory einfügen
    if (namenullp(pathname)) { fehler_noname(pathname); } # Kein Name angegeben -> Fehler
    # Name angegeben.
    pushSTACK(pathname);
    # Directory muss existieren:
    var object namestring = assure_dir_exists(false,true); # Filename fürs Betriebssystem
    if (eq(namestring,nullobj)) {
      # Pfad zur Datei existiert nicht -> Wert NIL
      skipSTACK(1); value1 = NIL; mv_count=1; return;
    }
    if (openp(STACK_0)) { fehler_delete_open(STACK_0); } # Keine offenen Dateien löschen!
    # Datei löschen:
    #ifdef FILE_EXISTS_TRIVIAL
    if (!file_exists(namestring)) {
      skipSTACK(1); value1 = NIL; mv_count=1; return; # File existiert nicht -> Wert NIL
    }
    #endif
    with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
      if (!delete_file_if_exists(namestring_asciz)) {
        # File existiert nicht -> Wert NIL
        FREE_DYNAMIC_ARRAY(namestring_asciz); skipSTACK(1);
        value1 = NIL; mv_count=1; return;
      }
    });
    # Datei existierte, wurde gelöscht -> Pathname (/=NIL) als Wert
    value1 = popSTACK(); mv_count=1;
  }

# Fehlermeldung wegen Umbenennungsversuch einer geöffneten Datei
# fehler_rename_open(pathname);
# > pathname: Truename der Datei
  nonreturning_function(local, fehler_rename_open, (object pathname));
  local void fehler_rename_open(pathname)
    var object pathname;
    {
      pushSTACK(pathname); # Wert für Slot PATHNAME von FILE-ERROR
      pushSTACK(pathname);
      fehler(file_error,
             GETTEXT("cannot rename file ~ since there is file stream open to it")
            );
    }

# UP: Führt eine Datei-Umbenennung durch.
# rename_file();
# > Stackaufbau: filename, newname, oldpathname.
# < Stackaufbau: filename, newname, oldpathname, newpathname,
#                oldtruename, oldnamestring, newtruename, newnamestring.
  local void rename_file (void);
  local void rename_file()
    {
      # 1. newpathname := (MERGE-PATHNAMES newname oldpathname)
      {
        pushSTACK(STACK_1); # newname als 1. Argument
        pushSTACK(STACK_(0+1)); # oldpathname als 2. Argument
        funcall(L(merge_pathnames),2);
        pushSTACK(value1);
      }
      # Stackaufbau: filename, newname, oldpathname, newpathname.
      # 2. oldpathname überprüfen:
      {
        var object oldpathname = STACK_1;
        check_no_wildcards(oldpathname); # mit Wildcards -> Fehler
        oldpathname = use_default_dir(oldpathname); # Default-Directory einfügen
        if (namenullp(oldpathname)) { fehler_noname(oldpathname); } # Kein Name angegeben -> Fehler
        # Name angegeben.
        pushSTACK(oldpathname);
        # Directory muss existieren:
        var object old_namestring = assure_dir_exists(false,false); # Filename fürs Betriebssystem
        if (openp(STACK_0)) { fehler_rename_open(STACK_0); } # Keine offenen Dateien umbenennen!
        pushSTACK(old_namestring);
      }
      # Stackaufbau: filename, newname, oldpathname, newpathname,
      #              oldtruename, oldnamestring.
      # 3. newpathname überprüfen:
      {
        var object newpathname = coerce_pathname(STACK_2);
        check_no_wildcards(newpathname); # mit Wildcards -> Fehler
        newpathname = use_default_dir(newpathname); # Default-Directory einfügen
        if (namenullp(newpathname)) { fehler_noname(newpathname); } # Kein Name angegeben -> Fehler
        # Name angegeben.
        pushSTACK(newpathname);
        # Directory muss existieren:
        var object new_namestring = assure_dir_exists(false,false); # Filename fürs Betriebssystem
        # Stackaufbau: filename, newname, oldpathname, newpathname,
        #              oldtruename, oldnamestring, newtruename.
        # 4. Datei umbenennen:
        if (file_exists(new_namestring)) {
          # Datei existiert bereits -> nicht ohne Vorwarnung löschen
          fehler_file_exists(S(rename_file),STACK_0);
        }
        pushSTACK(new_namestring);
      }
      # Stackaufbau: filename, newname, oldpathname, newpathname,
      #              oldtruename, oldnamestring, newtruename, newnamestring.
      # Nun kann gefahrlos umbenannt werden:
      prepare_create(STACK_4);
      with_sstring_0(STACK_2,O(pathname_encoding),oldnamestring_asciz, {
        with_sstring_0(STACK_0,O(pathname_encoding),newnamestring_asciz, {
          rename_file_to_nonexisting(oldnamestring_asciz,newnamestring_asciz);
        });
      });
    }

LISPFUNN(rename_file,2)
# (RENAME-FILE filename newname), CLTL S. 423
  {
    var object filename = STACK_1; # filename-Argument
    if (builtin_stream_p(filename)) {
      # Stream -> extra behandeln:
      # muss File-Stream sein:
      filename = as_file_stream(filename);
      test_file_stream_named(filename);
      # Streamtyp File-Stream -> Truename verwenden:
      filename = TheStream(filename)->strm_file_truename;
      pushSTACK(filename);
      # Umbenennen:
      rename_file();
      # Stream aktualisieren:
      filename = STACK_7;
      TheStream(filename)->strm_file_name = STACK_4; # newpathname als neuer Name
      TheStream(filename)->strm_file_truename = STACK_1; # newtruename als neuer Truename
      # Handle etc. unverändert lassen
    } else {
      filename = coerce_pathname(filename); # zu einem Pathname machen
      pushSTACK(filename);
      # Umbenennen:
      rename_file();
    }
    value1 = STACK_4; # newpathname als 1. Wert
    value2 = STACK_3; # oldtruename als 2. Wert
    value3 = STACK_1; # newtruename als 3. Wert
    mv_count=3; skipSTACK(8); # 3 Werte
  }

# Create a file.
# create_new_file(pathstring);
# It is known that the file does not already exist.
# > pathstring: file name, ASCIZ-String
# > STACK_0: pathname
  local inline void create_new_file (char* pathstring);
  local inline void create_new_file(pathstring)
    var char* pathstring;
    {
      #ifdef AMIGAOS
        begin_system_call();
        var Handle handle = Open(pathstring,MODE_NEWFILE);
        if (handle == Handle_NULL) { end_system_call(); OS_file_error(STACK_0); } # Error melden
        # Datei wurde erzeugt, handle ist das Handle.
        # Datei wieder schließen:
        (void) Close(handle);
        end_system_call();
      #endif
      #ifdef WIN32_NATIVE
        begin_system_call();
        var Handle handle = CreateFile(pathstring, 0, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
        if (handle==INVALID_HANDLE_VALUE) { end_system_call(); OS_file_error(STACK_0); }
        # Datei wurde erzeugt, handle ist das Handle.
        # Datei wieder schließen:
        if (!CloseHandle(handle)) { end_system_call(); OS_file_error(STACK_0); }
        end_system_call();
      #endif
      #ifdef EMUNIX
        begin_system_call();
        var int result = creat(pathstring,my_open_mask);
        if (result<0) { end_system_call(); OS_file_error(STACK_0); } # Error melden
        setmode(ergebnis,O_BINARY);
        # Datei wurde erzeugt, ergebnis ist das Handle.
        # Datei wieder schließen:
        if (!(CLOSE(result)==0)) { end_system_call(); OS_file_error(STACK_0); } # Error melden
        end_system_call();
      #endif
      #if defined(UNIX) || defined(RISCOS)
        begin_system_call();
        var int result = OPEN(pathstring, O_WRONLY | O_BINARY | O_CREAT | O_TRUNC, my_open_mask);
        if (result<0) { end_system_call(); OS_file_error(STACK_0); } # Error melden
        # Datei wurde erzeugt, ergebnis ist das Handle.
        # Datei wieder schließen:
        if (!(CLOSE(result)==0)) { end_system_call(); OS_file_error(STACK_0); } # Error melden
        end_system_call();
      #endif
    }

# Open a file for input.
# open_input_file(pathstring,create_if_not_exists,&handle)
# > vorausgegangen: assure_dir_exists()
# > pathstring: file name, ASCIZ-String
# > create_if_not_exists: if true, the file must be created
# > STACK_0: pathname
# < handle: open file handle
# < result: whether the file could be opened (necessarily true if create_if_not_exists)
  local inline bool open_input_file (char* pathstring, bool create_if_not_exists, Handle* handle_);
  local inline bool open_input_file(pathstring,create_if_not_exists,handle_)
    var char* pathstring;
    var bool create_if_not_exists;
    var Handle* handle_;
    {
      #ifdef EMUNIX
        var sintW result;
        # Datei zu öffnen versuchen:
        #ifdef FILE_EXISTS_TRIVIAL
          if (file_exists(_EMA_)) {
            begin_system_call();
            result = open(pathstring,O_RDONLY);
          } else {
            # Datei existiert nicht
            if (!create_if_not_exists) return false;
            # Datei mit creat erzeugen:
            begin_system_call();
            result = creat(pathstring,my_open_mask);
          }
          if (result<0) {
            end_system_call(); OS_file_error(STACK_0);
          }
        #else
          # erst mit open erfragen, ob die Datei existiert:
          begin_system_call();
          result = open(pathstring,O_RDONLY);
          if (result<0) {
            if (errno == ENOENT) { # nicht gefunden?
              # Datei existiert nicht
              if (!create_if_not_exists) { end_system_call(); return false; }
              # Datei mit creat erzeugen:
              result = creat(pathstring,my_open_mask);
              if (result<0) { end_system_call(); OS_file_error(STACK_0); }
            } else {
              end_system_call(); OS_file_error(STACK_0); # sonstigen Error melden
            }
          }
        #endif
        setmode(result,O_BINARY);
        end_system_call();
        *handle_ = result; return true;
      #endif
      #ifdef AMIGAOS
        var Handle handle;
        #ifdef FILE_EXISTS_TRIVIAL
          if (file_exists(_EMA_)) {
            begin_system_call();
            handle = Open(pathstring,MODE_OLDFILE);
          } else {
            # Datei existiert nicht
            if (!create_if_not_exists) return false;
            # Datei mit Open erzeugen:
            begin_system_call();
            handle = Open(pathstring,MODE_READWRITE);
          }
        #else
          # erst mit Open erfragen, ob die Datei existiert:
          begin_system_call();
          handle = Open(pathstring,MODE_OLDFILE);
          if (handle==Handle_NULL) {
            if (IoErr()==ERROR_OBJECT_NOT_FOUND) {
              # Datei existiert nicht
              if (!create_if_not_exists) { end_system_call(); return false; }
              # Datei mit Open erzeugen:
              handle = Open(pathstring,MODE_READWRITE);
            }
          }
        #endif
        end_system_call();
        if (handle==Handle_NULL) { OS_file_error(STACK_0); }
        *handle_ = handle; return true;
      #endif
      #if defined(UNIX) || defined(RISCOS)
        var int result;
        #ifdef FILE_EXISTS_TRIVIAL
          var int oflags = O_RDONLY | O_BINARY;
          if (!file_exists(_EMA_)) {
            # Datei existiert nicht
            if (!create_if_not_exists) return false;
            # Datei mit open erzeugen:
            oflags |= O_CREAT;
          }
          begin_system_call();
          result = OPEN(pathstring,oflags,my_open_mask);
          end_system_call();
          if (result<0) { OS_file_error(STACK_0); }
        #else
          var int oflags = O_RDONLY | O_BINARY;
          if (create_if_not_exists) { oflags |= O_CREAT; }
          begin_system_call();
          result = OPEN(pathstring,oflags,my_open_mask);
          if (result<0) {
            if (errno == ENOENT) { # nicht gefunden?
              # Datei existiert nicht
              if (!create_if_not_exists) { end_system_call(); return false; }
            }
            end_system_call(); OS_file_error(STACK_0); # sonstigen Error melden
          }
          end_system_call();
        #endif
        *handle_ = result; return true;
      #endif
      #ifdef WIN32_NATIVE
        var Handle handle;
        #ifdef FILE_EXISTS_TRIVIAL
          var DWORD flag = OPEN_EXISTING;
          if (!file_exists(_EMA_)) {
            # Datei existiert nicht
            if (!create_if_not_exists) return false;
            # Datei mit CreateFile erzeugen:
            flag = OPEN_ALWAYS;
          }
          begin_system_call();
          handle = CreateFile(pathstring, GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE,
                              NULL, flag, FILE_ATTRIBUTE_NORMAL, NULL);
          end_system_call();
          if (handle==INVALID_HANDLE_VALUE) { OS_file_error(STACK_0); }
        #else
          var DWORD flag = OPEN_EXISTING;
          if (create_if_not_exists) { flag = OPEN_ALWAYS; }
          begin_system_call();
          handle = CreateFile(pathstring, GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE,
                              NULL, flag, FILE_ATTRIBUTE_NORMAL, NULL);
          if (handle==INVALID_HANDLE_VALUE) {
            if (GetLastError()==ERROR_FILE_NOT_FOUND || GetLastError()==ERROR_PATH_NOT_FOUND || GetLastError()==ERROR_BAD_NETPATH) { # nicht gefunden?
              # Datei existiert nicht
              if (!create_if_not_exists) { end_system_call(); return false; }
            }
            end_system_call(); OS_file_error(STACK_0); # sonstigen Error melden
          }
          end_system_call();
        #endif
        *handle_ = handle; return true;
      #endif
    }

#if defined(UNIX) || defined(AMIGAOS) || defined(RISCOS) || defined(WIN32_NATIVE)
# Open a file for output.
# open_output_file(pathstring,truncate_if_exists)
# > pathstring: file name, ASCIZ-String
# > truncate_if_exists: if true, the file is truncated to zero size
# > STACK_0: pathname
# < result: open file handle
  local inline Handle open_output_file (char* pathstring, bool truncate_if_exists);
  local inline Handle open_output_file(pathstring,truncate_if_exists)
    var char* pathstring;
    var bool truncate_if_exists;
    {
      #ifdef AMIGAOS
        begin_system_call();
        var Handle handle = Open(pathstring, (truncate_if_exists ? MODE_NEWFILE : MODE_READWRITE));
        end_system_call();
        if (handle==Handle_NULL) { OS_file_error(STACK_0); } # Error melden
        return handle;
      #endif
      #if defined(UNIX) || defined(RISCOS)
        begin_system_call();
        var int result =
          OPEN(pathstring,
               (truncate_if_exists ? O_RDWR | O_BINARY | O_CREAT | O_TRUNC
                                   : O_RDWR | O_BINARY | O_CREAT),
               my_open_mask);
        end_system_call();
        if (result<0) { OS_file_error(STACK_0); } # Error melden
        return result;
      #endif
      #ifdef WIN32_NATIVE
        begin_system_call();
        var Handle handle = CreateFile(pathstring, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE,
                            NULL, (truncate_if_exists ? CREATE_ALWAYS : OPEN_ALWAYS), FILE_ATTRIBUTE_NORMAL, NULL);
        end_system_call();
        if (handle==INVALID_HANDLE_VALUE) { OS_file_error(STACK_0); }
        return handle;
      #endif
    }
#endif

# Create a backup file before opening a file for output.
# create_backup_file(pathstring,delete_backup_file);
# > vorausgegangen: assure_dir_exists()
# > pathstring: file name, ASCIZ-String
# > delete_backup_file: if true, delete the backup file
# > STACK_0: pathname
  local inline void create_backup_file (char* pathstring, bool delete_backup_file);
  local inline void create_backup_file(pathstring,delete_backup_file)
    var char* pathstring;
    var bool delete_backup_file;
    {
      var object filename = STACK_0;
      if (openp(filename))
        fehler_rename_open(filename); # Keine offenen Dateien umbenennen!
      var object new_namestring;
      #ifdef EMUNIX
        # Truename mit ".bak" erweitern:
        # filename := (merge-pathnames ".bak" filename) :
        filename = copy_pathname(filename); # kopieren
        ThePathname(filename)->pathname_type = O(backuptype_string); # mit Extension "BAK"
        if (openp(filename)) { fehler_delete_open(filename); } # Keine offenen Dateien löschen!
        pushSTACK(filename);
        # Directory existiert schon.
        new_namestring = assume_dir_exists(); # Filename fürs Betriebssystem
      #endif
      #if defined(UNIX) || defined(AMIGAOS) || defined(WIN32_NATIVE)
        # Truename mit "%" bzw. ".bak" bzw. "~" erweitern:
        # filename := (parse-namestring (concatenate 'string (namestring filename) "%")) :
        filename = whole_namestring(filename); # als String
        pushSTACK(filename); pushSTACK(O(backupextend_string)); # "%"
        filename = string_concat(2); # dazuhängen
        pushSTACK(filename); # retten
        pushSTACK(filename); # retten
        filename = coerce_pathname(filename); # wieder als Filename
        if (openp(filename)) { fehler_delete_open(filename); } # Keine offenen Dateien löschen!
        STACK_1 = filename;
        # Directory existiert schon. Hier keine weiteren Links verfolgen.
        new_namestring = popSTACK(); # Filename fürs Betriebssystem
      #endif
      #ifdef RISCOS
        # Dem Namen ein "~" voranstellen:
        filename = copy_pathname(filename);
        pushSTACK(filename);
        pushSTACK(O(backupprepend_string)); pushSTACK(ThePathname(filename)->pathname_name);
        {
          var object new_name = string_concat(2);
          filename = STACK_0;
          ThePathname(filename)->pathname_name = new_name;
        }
        if (openp(filename)) { fehler_delete_open(filename); } # Keine offenen Dateien löschen!
        new_namestring = assure_dir_exists(false,false); # Filename fürs Betriebssystem
      #endif
      with_sstring_0(new_namestring,O(pathname_encoding),new_namestring_asciz, {
        # Datei (oder Link) mit diesem Namen löschen, falls vorhanden:
        delete_file_before_rename(new_namestring_asciz);
        # Datei vom alten auf diesen Namen umbenennen:
        rename_existing_file(pathstring,new_namestring_asciz);
        if (delete_backup_file) { delete_existing_file(new_namestring_asciz); }
      });
      skipSTACK(1);
    }

# UP: erzeugt ein File-Stream
# open_file(filename,direction,if_exists,if_not_exists)
# > STACK_3: original filename (may be logical)
# > STACK_2: :BUFFERED argument
# > STACK_1: :EXTERNAL-FORMAT argument
# > STACK_0: :ELEMENT-TYPE argument
# > filename: Filename, ein Pathname
# > direction: Modus (0 = :PROBE, 1 = :INPUT, 4 = :OUTPUT, 5 = :IO, 3 = :INPUT-IMMUTABLE)
# > if_exists: :IF-EXISTS-Argument
#         (0 = nichts, 1 = :ERROR, 2 = NIL,
#          3 = :RENAME, 4 = :RENAME-AND-DELETE, 5 = :NEW-VERSION,:SUPERSEDE,
#          6 = :APPEND, 7 = :OVERWRITE)
# > if_not_exists: :IF-DOES-NOT-EXIST-Argument
#         (0 = nichts, 1 = :ERROR, 2 = NIL, 3 = :CREATE)
# < ergebnis: Stream oder NIL
# < STACK: aufgeräumt
# can trigger GC
  local object open_file (object filename, uintB direction, uintB if_exists, uintB if_not_exists);
  local object open_file(filename,direction,if_exists,if_not_exists)
    var object filename;
    var uintB direction;
    var uintB if_exists;
    var uintB if_not_exists;
    {
      pushSTACK(STACK_3); # Filename retten
      check_no_wildcards(filename); # mit Wildcards -> Fehler
      filename = use_default_dir(filename); # Default-Directory einfügen
      if (namenullp(filename)) { fehler_noname(filename); } # Kein Name angegeben -> Fehler
      pushSTACK(filename); # absPathname retten
      # Stackaufbau: origPathname, absPathname.
      # Directory muss existieren:
      var object namestring = # Filename fürs Betriebssystem
        assure_dir_exists(false,((direction == 0) && (if_not_exists == 0)) || (if_not_exists == 2)); # tolerant only if :PROBE and if_not_exists = 0 or if if_not_exists = 2
      if (eq(namestring,nullobj))
        # Pfad zur Datei existiert nicht, und :IF-DOES-NOT-EXIST = nichts oder NIL
        goto ergebnis_NIL;
      # Stackaufbau: Pathname, Truename.
      # Filename überprüfen und Handle holen:
      var object handle;
      var bool append_flag = false;
      switch (direction) {
        case 0: # Modus ist :PROBE
          if (!file_exists(namestring)) {
            # Datei existiert nicht
            # :IF-DOES-NOT-EXIST-Argument entscheidet:
            if (if_not_exists==1) # :ERROR -> Error
              goto fehler_notfound;
            if (!(if_not_exists==3)) # nichts oder NIL -> NIL
              goto ergebnis_NIL;
            # :CREATE -> Datei mit open erzeugen und schließen:
            with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
              prepare_create(STACK_0);
              create_new_file(namestring_asciz);
            });
          }
          handle = NIL; # Handle := NIL
          break;
        case 1: case 3: # Modus ist :INPUT
          {
            var Handle handl;
            var bool result;
            #ifdef PATHNAME_RISCOS
            if (!file_exists(namestring)) {
              pushSTACK(namestring); prepare_create(STACK_1); namestring = popSTACK();
            }
            #endif
            with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
              result = open_input_file(namestring_asciz,if_not_exists==3,&handl);
            });
            if (!result) {
              # :IF-DOES-NOT-EXIST-Argument entscheidet:
              if (if_not_exists==2) # NIL -> NIL
                goto ergebnis_NIL;
              else # nichts oder :ERROR -> Error
                goto fehler_notfound;
            }
            handle = allocate_handle(handl);
          }
          break;
        default: # Modus ist :OUTPUT oder :IO
          # Defaultwert für if_not_exists ist von if_exists abhängig:
          if (if_not_exists==0) { # falls if_not_exists nicht angegeben:
            if (if_exists<6) # if_exists = :APPEND oder :OVERWRITE -> if_not_exists unverändert
              if_not_exists = 3; # weder :APPEND noch :OVERWRITE -> Default ist :CREATE
          }
          # Defaultwert für if_exists ist :NEW-VERSION :
          if (if_exists==0)
            if_exists = 5;
          #ifdef EMUNIX
            with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
              # Bei if_exists=5 und if_not_exists=3 kann man sofort
              # CREAT ansteuern, sonst muss man vorher OPEN versuchen:
              if (!((if_exists==5) && (if_not_exists==3))) {
                begin_system_call();
                var sintW ergebnis = # Datei zu öffnen versuchen
                  open(namestring_asciz,O_RDWR);
                if (ergebnis<0) {
                  if (errno == ENOENT) { # nicht gefunden?
                    # Datei existiert nicht
                    end_system_call();
                    # :IF-DOES-NOT-EXIST-Argument entscheidet:
                    if (if_not_exists<2) # (Default bei :APPEND oder :OVERWRITE) oder :ERROR ?
                      goto fehler_notfound;
                    if (if_not_exists==2) # NIL -> NIL
                      goto ergebnis_NIL;
                    # :CREATE
                  } else {
                    end_system_call(); OS_file_error(STACK_0); # sonstigen Error melden
                  }
                } else {
                  # Datei existiert, ergebnis ist das Handle
                  # :IF-EXISTS-Argument entscheidet:
                  switch (if_exists) {
                    case 1: # :ERROR -> schließen und Error
                      if (CLOSE(ergebnis) < 0) {
                        end_system_call(); OS_file_error(STACK_0); # Error melden
                      }
                      end_system_call();
                      goto fehler_exists;
                    case 2: # NIL -> schließen und NIL
                      if (CLOSE(ergebnis) < 0) {
                        end_system_call(); OS_file_error(STACK_0); # Error melden
                      }
                      end_system_call();
                      goto ergebnis_NIL;
                    case 6: # :APPEND
                      append_flag = true; # am Schluss ans Ende positionieren
                    case 7: # :OVERWRITE -> bestehende Datei benutzen
                      setmode(ergebnis,O_BINARY);
                      end_system_call();
                      handle = allocate_handle(ergebnis);
                      goto handle_ok;
                    default: ;
                      # :RENAME, :RENAME-AND-DELETE -> Datei umbenennen und dann neu eröffnen.
                      # :NEW-VERSION, :SUPERSEDE -> Datei auf Länge 0 kürzen.
                  }
                  # In beiden Fällen erst die Datei schließen:
                  if (CLOSE(ergebnis) < 0) {
                    end_system_call(); OS_file_error(STACK_0); # Error melden
                  }
                  end_system_call();
                  if ((if_exists==3) || (if_exists==4)) {
                    # :RENAME oder :RENAME-AND-DELETE -> umbenennen:
                    create_backup_file(namestring_asciz,if_exists==4);
                  }
                }
              }
              # Datei mit CREAT erzeugen:
              begin_system_call();
              var sintW ergebnis = # erzeugen
                creat(namestring_asciz,my_open_mask);
              if (ergebnis<0) {
                end_system_call(); OS_file_error(STACK_0); # Error melden
              }
              setmode(ergebnis,O_BINARY);
              end_system_call();
              # Datei neu erzeugt, ergebnis ist das Handle
              handle = allocate_handle(ergebnis);
            });
          #endif
          #if defined(UNIX) || defined(AMIGAOS) || defined(RISCOS) || defined(WIN32_NATIVE)
            with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
              if (file_exists(namestring)) {
                # Datei existiert
                # :IF-EXISTS-Argument entscheidet:
                switch (if_exists) {
                  case 1: # :ERROR -> Error
                    goto fehler_exists;
                  case 2: # NIL -> NIL
                    goto ergebnis_NIL;
                  case 3: case 4: # :RENAME oder :RENAME-AND-DELETE -> umbenennen:
                    create_backup_file(namestring_asciz,if_exists==4);
                    break;
                  case 6: # :APPEND
                    append_flag = true; # am Schluss ans Ende positionieren
                  default: ;
                    # :OVERWRITE -> bestehende Datei benutzen
                    # :NEW-VERSION, :SUPERSEDE -> Datei auf Länge 0 kürzen.
                }
              } else {
                # Datei existiert nicht
                # :IF-DOES-NOT-EXIST-Argument entscheidet:
                if (if_not_exists<2) # (Default bei :APPEND oder :OVERWRITE) oder :ERROR ?
                  goto fehler_notfound;
                if (if_not_exists==2) # NIL -> NIL
                  goto ergebnis_NIL;
                # :CREATE
              }
              prepare_create(STACK_0);
              # Datei mit open öffnen:
              # if-exists-Handling: bei if_exists<=5 Inhalt löschen,
              # sonst (bei :APPEND, :OVERWRITE) bestehenden Inhalt lassen.
              # if-not-exists-Handling: neue Datei erzeugen.
              var Handle handl = open_output_file(namestring_asciz,if_exists<=5);
              handle = allocate_handle(handl);
            });
          #endif
          break;
         fehler_notfound: # Fehler, da Datei nicht gefunden
          # STACK_0 = Truename, Wert für Slot PATHNAME von FILE-ERROR
          pushSTACK(STACK_0);
          fehler(file_error,
                 GETTEXT("file ~ does not exist")
                );
         fehler_exists: # Fehler, da Datei bereits existiert
          # STACK_0 = Truename, Wert für Slot PATHNAME von FILE-ERROR
          pushSTACK(STACK_0);
          fehler(file_error,
                 GETTEXT("a file named ~ already exists")
                );
      }
     handle_ok:
      # handle und append_flag sind jetzt fertig.
      # Stream erzeugen:
      pushSTACK(STACK_4); # :BUFFERED argument
      pushSTACK(STACK_4); # :EXTERNAL-FORMAT argument
      pushSTACK(STACK_4); # :ELEMENT-TYPE argument
      pushSTACK(handle);
      var object stream = make_file_stream(direction,append_flag,true);
      skipSTACK(4);
      return stream;
     ergebnis_NIL: # Ergebnis NIL
      skipSTACK(6); # beide Pathnames und drei Argumente vergessen
      return NIL;
    }

LISPFUN(open,1,0,norest,key,6,\
        (kw(direction),kw(element_type),kw(if_exists),kw(if_does_not_exist),kw(external_format),kw(buffered)) )
# (OPEN filename :direction :element-type :if-exists :if-does-not-exist :external-format :buffered)
  {
    var object filename = STACK_6; # filename
    if (builtin_stream_p(filename)) {
      # muss File-Stream sein:
      filename = as_file_stream(filename);
      test_file_stream_named(filename);
      # Streamtyp File-Stream -> Truename verwenden:
      filename = TheStream(filename)->strm_file_truename;
      pushSTACK(filename);
    } else {
      filename = coerce_xpathname(filename); # zu einem Pathname machen
      pushSTACK(filename);
      #ifdef LOGICAL_PATHNAMES
      # Convert from logical to physical pathname:
      if (logpathnamep(filename))
        filename = coerce_pathname(filename);
      #endif
    }
    # Stack layout: filename-arg, direction, element-type, if-exists, if-does-not-exist, external-format, buffered, origpathname.
    # filename ist jetzt ein Pathname.
    var uintB direction;
    var uintB if_exists;
    var uintB if_not_exists;
    # :direction überprüfen und in direction übersetzen:
    {
      var object arg = STACK_(5+1);
      if (eq(arg,unbound) || eq(arg,S(Kinput))) {
        direction = 1;
      } elif (eq(arg,S(Kinput_immutable))) {
        direction = 3;
      } elif (eq(arg,S(Koutput))) {
        direction = 4;
      } elif (eq(arg,S(Kio))) {
        direction = 5;
      } elif (eq(arg,S(Kprobe))) {
        direction = 0;
      } else {
        pushSTACK(arg); # Wert für Slot DATUM von TYPE-ERROR
        pushSTACK(O(type_direction)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
        pushSTACK(arg); pushSTACK(S(open));
        fehler(type_error,
               GETTEXT("~: illegal :DIRECTION argument ~")
              );
      }
    }
    # :element-type wird später überprüft.
    # :if-exists überprüfen und in if_exists übersetzen:
    {
      var object arg = STACK_(3+1);
      if (eq(arg,unbound)) {
        if_exists = 0;
      } elif (eq(arg,S(Kerror))) {
        if_exists = 1;
      } elif (eq(arg,NIL)) {
        if_exists = 2;
      } elif (eq(arg,S(Krename))) {
        if_exists = 3;
      } elif (eq(arg,S(Krename_and_delete))) {
        if_exists = 4;
      } elif (eq(arg,S(Knew_version)) || eq(arg,S(Ksupersede))) {
        if_exists = 5;
      } elif (eq(arg,S(Kappend))) {
        if_exists = 6;
      } elif (eq(arg,S(Koverwrite))) {
        if_exists = 7;
      } else {
        pushSTACK(arg); # Wert für Slot DATUM von TYPE-ERROR
        pushSTACK(O(type_if_exists)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
        pushSTACK(arg); pushSTACK(S(open));
        fehler(type_error,
               GETTEXT("~: illegal :IF-EXISTS argument ~")
              );
      }
    }
    # :if-does-not-exist überprüfen und in if_not_exists übersetzen:
    {
      var object arg = STACK_(2+1);
      if (eq(arg,unbound)) {
        if_not_exists = 0;
      } elif (eq(arg,S(Kerror))) {
        if_not_exists = 1;
      } elif (eq(arg,NIL)) {
        if_not_exists = 2;
      } elif (eq(arg,S(Kcreate))) {
        if_not_exists = 3;
      } else {
        pushSTACK(arg); # Wert für Slot DATUM von TYPE-ERROR
        pushSTACK(O(type_if_does_not_exist)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
        pushSTACK(arg); pushSTACK(S(open));
        fehler(type_error,
               GETTEXT("~: illegal :IF-DOES-NOT-EXIST argument ~")
              );
      }
    }
    # :external-format wird später überprüft.
    # :buffered wird später überprüft.
    # File öffnen:
    STACK_4 = STACK_5; STACK_5 = STACK_2; STACK_6 = STACK_1; STACK_7 = STACK_0;
    skipSTACK(4);
    value1 = open_file(filename,direction,if_exists,if_not_exists);
    mv_count=1;
  }

# UP: Liefert eine Liste aller matchenden Pathnames.
# directory_search(pathname)
# > pathname: Pathname mit Device /= :WILD
#ifdef UNIX
# > STACK_1: Circle-Flag
#endif
# > STACK_0: Full-Flag
# < ergebnis:
#     Falls name=NIL und type=NIL:     Liste aller matchenden Directories,
#     sonst (name=NIL -> name=:WILD):  Liste aller matchenden Dateien.
#     Jeweils als absoluter Pathname ohne Wildcards,
#     bzw. bei Dateien und Full-Flag /=NIL als Liste
#          (Pathname Write-Date Length)
#          mit  Pathname ohne :WILD/:WILD-INFERIORS-Komponenten,
#               Write-Date = Datum der Dateierstellung (ss mm hh dd mm yy),
#                 als Decoded-Time passend für ENCODE-UNIVERSAL-TIME,
#               Length = Länge der Datei (in Bytes).
# can trigger GC
  local object directory_search (object pathname);
  # Methode: Breadth-first-search, damit nur eine Suchoperation gleichzeitig
  # läuft.
  #
  #if defined(MSDOS) || defined(WIN32_NATIVE)
    # Common set of macros for directory search.
    #ifdef MSDOS
      #define READDIR_wildnametype_suffix  O(wild_wild_string) # "*.*"
      #define READDIR_var_declarations  \
        var struct ffblk DTA_buffer; \
        set_break_sem_4(); # wegen DTA-Buffer gegen Unterbrechungen sperren
      #define READDIR_end_declarations  \
        clr_break_sem_4();
      #define READDIR_findfirst(pathstring,error_statement,done_statement)  \
        if (findfirst(pathstring,&DTA_buffer,FA_DIREC|FA_ARCH|FA_RDONLY) <0) \
          { if (!((errno==ENOENT) || (errno==ENOMORE)))                      \
              { error_statement }                                            \
            else                                                             \
              { done_statement }                                             \
          }
      #define READDIR_findnext(error_statement,done_statement)  \
        if (findnext(&DTA_buffer) <0)                                        \
          { if (!((errno==ENOENT) || (errno==ENOMORE)))                      \
              { error_statement }                                            \
            else                                                             \
              { done_statement }                                             \
          }
      #define READDIR_entry_name()  (&DTA_buffer.ff_name[0])
      #define READDIR_entry_ISDIR()  (DTA_buffer.ff_attrib & FA_DIREC)
      #define READDIR_entry_timedate(timepointp)  \
        convert_timedate((uintW)DTA_buffer.ff_ftime,(uintW)DTA_buffer.ff_fdate,timepointp);
      #define READDIR_entry_size()  (*(uintL*)(&DTA_buffer.ff_fsize))
    #endif
    #ifdef WIN32_NATIVE
      #define READDIR_wildnametype_suffix  O(wild_string) # "*"
      #define READDIR_var_declarations  \
        var WIN32_FIND_DATA filedata; \
        var HANDLE search_handle;
      #define READDIR_end_declarations
      #define READDIR_findfirst(pathstring,error_statement,done_statement)  \
        if ((search_handle = FindFirstFile(pathstring,&filedata)) == INVALID_HANDLE_VALUE) \
          { if (!(GetLastError()==ERROR_FILE_NOT_FOUND || GetLastError()==ERROR_PATH_NOT_FOUND || GetLastError()==ERROR_BAD_NETPATH)) \
              { error_statement }                                                          \
            else                                                                           \
              { done_statement }                                                           \
          }
      #define READDIR_findnext(error_statement,done_statement)  \
        if (!FindNextFile(search_handle,&filedata))                                        \
          { if (!(GetLastError()==ERROR_NO_MORE_FILES) || !FindClose(search_handle))       \
              { error_statement }                                                          \
            else                                                                           \
              { done_statement }                                                           \
          }
      #define READDIR_entry_name()  (&filedata.cFileName[0])
      #define READDIR_entry_ISDIR()  (filedata.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
      #define READDIR_entry_timedate(timepointp)  \
        { var FILETIME* pftimepoint = &filedata.ftLastWriteTime;               \
          if (pftimepoint->dwLowDateTime==0 && pftimepoint->dwHighDateTime==0) \
            pftimepoint = &filedata.ftCreationTime;                            \
          convert_time(pftimepoint,timepointp);                                \
        }
      #define READDIR_entry_size()  filedata.nFileSizeLow
    #endif
  #endif
  #
  #if defined(UNIX) || defined(RISCOS)
  # Just like stat(), except that directories or files which would lead
  # to problems are silently hidden.
    local inline int stat_for_search (char* pathstring, struct stat * statbuf);
    local inline int stat_for_search(pathstring,statbuf)
      var char* pathstring;
      var struct stat * statbuf;
      {
        #ifdef UNIX_LINUX
          # Avoid searching /proc: It is a zoo containing strange animals:
          # directories which go away constantly, pseudo-regular files which
          # are really pipes, etc.
          if (asciz_equal(pathstring,"/proc")) { errno = ENOENT; return -1; }
        #endif
        var int result = stat(pathstring,statbuf);
        #ifdef UNIX_CYGWIN32
        if ((result < 0) && (errno == EACCES)) { errno = ENOENT; }
        #endif
        return result;
      }
  #endif
  #
  #if defined(PATHNAME_NOEXT) || defined(PATHNAME_RISCOS)
  #
  # UP: Erweitert das Directory eines Pathname um eine Komponente.
  # > STACK_1: ein Pathname
  # > STACK_0: neue Subdir-Komponente, ein Simple-String
  # < ergebnis: neuer Pathname mit um subdir verlängertem Directory
  # Erhöht STACK um 2
  # kann GC auslösen
  local object pathname_add_subdir (void);
  local object pathname_add_subdir()
    {
      # Pathname kopieren und dessen Directory gemäß
      # (append x (list y)) = (nreverse (cons y (reverse x))) verlängern:
      var object pathname = copy_pathname(STACK_1);
      STACK_1 = pathname;
      pushSTACK(reverse(ThePathname(pathname)->pathname_directory));
      var object new_cons = allocate_cons();
      Cdr(new_cons) = popSTACK();
      Car(new_cons) = popSTACK();
      new_cons = nreverse(new_cons);
      pathname = popSTACK();
      ThePathname(pathname)->pathname_directory = new_cons;
      return pathname;
    }
  #
  #if defined(UNIX) || defined(AMIGAOS) || defined(RISCOS)
  # UP: Erweitert einen Pathname um die File-Information.
  # > STACK_1: absoluter Pathname
  # > STACK_0: absoluter Pathname, Links aufgelöst
  # > *filestatus: dessen stat-Info
  # < STACK_0: Liste (Pathname Truename Write-Date Length [Kommentar]) im :FULL-Format
  local void with_stat_info (void);
  local void with_stat_info()
    {
      var object newlist;
      #if defined(UNIX) || defined(RISCOS)
      var uintL size = filestatus->st_size;
      #endif
      #ifdef AMIGAOS
      var uintL size = filestatus->fib_Size;
      #endif
      # Pathname schon in STACK_1, als 1. Listenelement
      # Truename schon in STACK_0, als 2. Listenelement
      {
        var decoded_time timepoint; # Write-Date in decodierter Form
        #if defined(UNIX) || defined(RISCOS)
        convert_time(&filestatus->st_mtime,&timepoint);
        #endif
        #ifdef AMIGAOS
        convert_time(&filestatus->fib_Date,&timepoint);
        #endif
        pushSTACK(timepoint.Sekunden);
        pushSTACK(timepoint.Minuten);
        pushSTACK(timepoint.Stunden);
        pushSTACK(timepoint.Tag);
        pushSTACK(timepoint.Monat);
        pushSTACK(timepoint.Jahr);
        newlist = listof(6); # 6-elementige Liste bauen
      }
      pushSTACK(newlist); # als 3. Listenelement
      pushSTACK(UL_to_I(size)); # Länge als 4. Listenelement
      #if defined(UNIX) || defined(RISCOS)
      newlist = listof(4); # 4-elementige Liste bauen
      #endif
      #ifdef AMIGAOS
      pushSTACK(asciz_to_string(&filestatus->fib_Comment[0],O(pathname_encoding))); # Kommentar als 5. Listenelement
      newlist = listof(5); # 5-elementige Liste bauen
      #endif
      pushSTACK(Car(newlist)); # pathname wieder in den Stack
      pushSTACK(newlist); # Liste in den Stack
    }
  #endif
  #
  # Check whether a directory exists.
  # check_stat_directory(namestring_asciz,error_statement,exists_statement);
  # If the directory does not exist or is a file, does nothing.
  #if defined(UNIX) || defined(RISCOS)
    #define check_stat_directory(namestring_asciz,error_statement,exists_statement)  \
      { var struct stat status;                                  \
        begin_system_call();                                     \
        if (!( stat(namestring_asciz,&status) ==0))              \
          { if (!(errno==ENOENT))                                \
              { end_system_call(); error_statement }             \
              else                                               \
              # Subdirectory existiert nicht -> OK.              \
              { end_system_call(); }                             \
          }                                                      \
          else                                                   \
          # File existiert.                                      \
          { end_system_call();                                   \
            if (S_ISDIR(status.st_mode)) # Ist es ein Directory? \
              { exists_statement }                               \
      }   }
  #endif
  #ifdef AMIGAOS
    #define check_stat_directory(namestring_asciz,error_statement,exists_statement)  \
      { var LONGALIGNTYPE(struct FileInfoBlock) fib;                       \
        var struct FileInfoBlock * fibptr = LONGALIGN(&fib);               \
        set_break_sem_4();                                                 \
        begin_system_call();                                               \
       {var BPTR lock = Lock(namestring_asciz,ACCESS_READ);                \
        if (lock==BPTR_NULL)                                               \
          { if (!(IoErr()==ERROR_OBJECT_NOT_FOUND))                        \
              { end_system_call(); clr_break_sem_4(); error_statement }    \
              else                                                         \
              # Subdirectory existiert nicht -> OK.                        \
              { end_system_call(); clr_break_sem_4(); }                    \
          }                                                                \
          else                                                             \
          # File existiert.                                                \
          { if (! Examine(lock,fibptr) )                                   \
              { UnLock(lock);                                              \
                end_system_call(); clr_break_sem_4();                      \
                error_statement                                            \
              }                                                            \
              else                                                         \
              { UnLock(lock);                                              \
                end_system_call(); clr_break_sem_4();                      \
                if (fibptr->fib_DirEntryType >= 0) # Ist es ein Directory? \
                  { exists_statement }                                     \
      }}  }   }
  #endif
  #ifdef WIN32_NATIVE
    #define check_stat_directory(namestring_asciz,error_statement,exists_statement)  \
      { var DWORD fileattr;                                                  \
        begin_system_call();                                                 \
        fileattr = GetFileAttributes(namestring_asciz);                      \
        if (fileattr == 0xFFFFFFFF)                                          \
          { if (!(GetLastError()==ERROR_FILE_NOT_FOUND || GetLastError()==ERROR_PATH_NOT_FOUND || GetLastError()==ERROR_BAD_NETPATH)) \
              { end_system_call(); error_statement }                         \
              else                                                           \
              # Subdirectory existiert nicht -> OK.                          \
              { end_system_call(); }                                         \
          }                                                                  \
          else                                                               \
          # File existiert.                                                  \
          { end_system_call();                                               \
            if (fileattr & FILE_ATTRIBUTE_DIRECTORY) # Ist es ein Directory? \
              { exists_statement }                                           \
      }   }
  #endif
  #
  #ifndef MSDOS
  # Search for a subdirectory with a given name.
  # directory_search_1subdir(subdir,namestring);
  # > STACK_0 = pathname
  # > STACK_(3+1) = new-pathname-list
  # > subdir: the new directory component to add to the pathname, if it exists
  # > namestring: the namestring (for the OS)
  # < STACK_0: replaced
  # < STACK_(3+1): augmented
  # kann GC auslösen
  local void directory_search_1subdir (object subdir, object namestring);
  local void directory_search_1subdir(subdir,namestring)
    var object subdir;
    var object namestring;
    {
      with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
        check_stat_directory(namestring_asciz,
                             { OS_file_error(STACK_0); },
          {
            # pathname kopieren und dessen Directory um subdir verlängern:
            pushSTACK(subdir);
            {
              var object pathname = pathname_add_subdir();
              pushSTACK(pathname);
            }
            # Diesen neuen Pathname vor new-pathname-list pushen:
            {
              var object new_cons = allocate_cons();
              Car(new_cons) = STACK_0;
              Cdr(new_cons) = STACK_(3+1);
              STACK_(3+1) = new_cons;
            }
          });
      });
    }
  #endif
  #
  #ifdef UNIX
  # Returns a truename dependent hash code for a directory.
  # directory_search_hashcode()
  # STACK_0 = dir_namestring
  # STACK_1 = pathname
  # < result: a hash code, or nullobj if the directory does not exist
  # kann GC auslösen
  local object directory_search_hashcode (void);
  local object directory_search_hashcode()
    {
      pushSTACK(STACK_0); # Directory-Name
      pushSTACK(O(punkt_string)); # und "."
      var object namestring = string_concat(2); # zusammenhängen
      var struct stat status;
      with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
        begin_system_call();
        if (!( stat(namestring_asciz,&status) ==0)) { # Information holen
          if (!(errno==ENOENT)) { end_system_call(); OS_file_error(STACK_1); }
          end_system_call();
          FREE_DYNAMIC_ARRAY(namestring_asciz);
          return nullobj;
        }
        end_system_call();
      });
      # Eintrag existiert (welch Wunder...)
      pushSTACK(UL_to_I(status.st_dev)); # Device-Nummer und
      pushSTACK(UL_to_I(status.st_ino)); # Inode-Nummer
      var object new_cons = allocate_cons(); # zusammenconsen
      Cdr(new_cons) = popSTACK(); Car(new_cons) = popSTACK();
      return new_cons;
    }
  #endif
  #
  #if defined(UNIX) || defined(RISCOS)
  # Tests whether a directory entry actually exists.
  # (It could be a link pointing to nowhere, or an undesired directory.)
  # directory_search_direntry_ok(namestring,&statbuf)
  # STACK_2 = pathname
  # < result: true and statbuf filled, or false.
  local bool directory_search_direntry_ok (object namestring, struct stat * statbuf);
  local bool directory_search_direntry_ok(namestring,statbuf)
    var object namestring;
    var struct stat * statbuf;
    {
      var bool exists = true;
      with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
        begin_system_call();
        if (!( stat_for_search(namestring_asciz,statbuf) ==0)) {
          if (!((errno==ENOENT) || (errno==ELOOP_VALUE))) {
            end_system_call(); OS_file_error(STACK_2);
          }
          end_system_call();
          exists = false;
        }
        end_system_call();
      });
      return exists;
    }
  #endif
  #
  # Scans an entire directory.
  # directory_search_scandir(recursively,next_task);
  # Stackaufbau: result-list, pathname, name&type, subdir-list, pathname-list,
  #              new-pathname-list, ht, pathname-list-rest, pathnames-to-insert,
  #              pathname, dir_namestring.
  local void directory_search_scandir (bool recursively, signean next_task);
  local void directory_search_scandir(recursively,next_task)
    var bool recursively;
    var signean next_task;
    {
      #if defined(UNIX) || defined(RISCOS)
        {
          var object namestring;
          #ifdef UNIX
          pushSTACK(STACK_0); # Directory-Name
          pushSTACK(O(punkt_string)); # und "."
          namestring = string_concat(2); # zusammenhängen
          #endif
          #ifdef RISCOS
          var object wildcard_mask;
          namestring = STACK_0; # Directory-Name
          namestring = subsstring(namestring,0,Sstring_length(namestring)-1); # Directory-Name ohne '.' am Schluss
          # Statt wildcard_match() selber aufzurufen, überlassen wir das dem Betriebssystem:
          wildcard_mask = (next_task<0 ? Car(STACK_(1+4+3)) : STACK_(2+4+3));
          #endif
          # Directory absuchen:
          var DIR* dirp;
          set_break_sem_4();
          #ifdef UNIX
          with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
            begin_system_call();
            dirp = opendir(namestring_asciz); # Directory öffnen
            end_system_call();
          });
          #endif
          #ifdef RISCOS
          with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
            with_sstring_0(wildcard_mask,O(pathname_encoding),wildcard_mask_asciz, {
              # In wildcard_mask_asciz die Wildchar-Characters '?' ins synonyme '#' umwandeln:
              {
                var uintB* ptr = wildcard_mask_asciz;
                while (*ptr != '\0') { if (*ptr == '?') { *ptr = '#'; } ptr++; }
              }
              begin_system_call();
              dirp = opendir(namestring_asciz,wildcard_mask_asciz); # Directory zum Suchen öffnen
              end_system_call();
            });
          });
          #endif
          if (dirp == (DIR*)NULL) { OS_file_error(STACK_1); }
          loop {
            var SDIRENT* dp;
            begin_system_call();
            errno = 0;
            dp = readdir(dirp); # nächsten Directory-Eintrag holen
            if (dp == (SDIRENT*)NULL) { # Error oder Directory zu Ende
              if (!(errno==0)) { end_system_call(); OS_file_error(STACK_1); }
              end_system_call();
              break;
            }
            end_system_call();
            # Directory-Eintrag in String umwandeln:
            var object direntry;
            {
              var uintL direntry_len;
              #if defined(UNIX_CYGWIN32)
              # Neither d_reclen nor d_namlen present in DIR structure.
              direntry_len = asciz_length(dp->d_name);
              #elif defined(DIRENT_WITHOUT_NAMLEN) || defined(__USE_GNU)
              # Unter UNIX_LINUX reichte früher direntry_len := dp->d_reclen, aber
              # i.a. ist direntry_len := min(dp->d_reclen,asciz_length(dp->d_name))
              # nötig. Die GNU libc ist buggy: macht "#define d_namlen d_reclen",
              # ebenso die Linux libc-5.0.9.
              {
                var const uintB* ptr = (const uintB*)(&dp->d_name[0]);
                var uintL count;
                direntry_len = 0;
                dotimesL(count,dp->d_reclen, {
                  if (*ptr == '\0') break;
                  ptr++; direntry_len++;
                });
              }
              #else
              direntry_len = dp->d_namlen;
              #endif
              direntry = n_char_to_string(&dp->d_name[0],direntry_len,O(pathname_encoding));
            }
            #ifndef RISCOS
            # "." und ".." übergehen:
            if (!(equal(direntry,O(punkt_string))
                  || equal(direntry,O(punktpunkt_string))
               ) )
            #endif
            {
              pushSTACK(direntry);
              # Stackaufbau: ..., pathname, dir_namestring, direntry.
              # Feststellen, ob es ein Directory oder ein File ist:
              pushSTACK(STACK_1); # Directory-Namestring
              pushSTACK(direntry); # direntry
              var object namestring = string_concat(2); # zusammenhängen
              # Information holen:
              var struct stat status;
              #if 1 # just an optimization
              if (!recursively) {
                # Try to avoid calling directory_search_direntry_ok(),
                # since it is an expensive operation (it calls stat()).
                if (next_task < 0) {
                  #ifndef RISCOS
                  # (car subdir-list) mit direntry matchen:
                  if (wildcard_match(Car(STACK_(1+4+3)),STACK_0))
                  #endif
                    if (directory_search_direntry_ok(namestring,&status))
                      if (S_ISDIR(status.st_mode))
                        goto push_matching_subdir;
                } elif (next_task > 0) {
                  #ifndef RISCOS
                  # name&type mit direntry matchen:
                  if (wildcard_match(STACK_(2+4+3),STACK_0))
                  #endif
                    if (directory_search_direntry_ok(namestring,&status))
                      if (!S_ISDIR(status.st_mode))
                        goto push_matching_file;
                }
                goto done_direntry;
              }
              #endif
              if (directory_search_direntry_ok(namestring,&status)) {
                # Eintrag existiert und ist nicht unerwünscht.
                if (S_ISDIR(status.st_mode)) { # Ist es ein Directory?
                  # Eintrag ist ein Directory.
                  if (recursively) { # alle rekursiven Subdirectories gewünscht?
                    # ja -> zu einem Pathname machen und auf
                    # pathnames-to-insert pushen (wird nachher
                    # vor pathname-list-rest eingefügt):
                    pushSTACK(STACK_2); pushSTACK(STACK_(0+1)); # pathname und direntry
                    {
                      var object pathname = pathname_add_subdir();
                      pushSTACK(pathname);
                    }
                    # Diesen neuen Pathname vor pathname-to-insert pushen:
                    {
                      var object new_cons = allocate_cons();
                      Car(new_cons) = popSTACK();
                      Cdr(new_cons) = STACK_(0+3);
                      STACK_(0+3) = new_cons;
                    }
                  }
                  if (next_task<0) {
                    #ifndef RISCOS
                    # (car subdir-list) mit direntry matchen:
                    if (wildcard_match(Car(STACK_(1+4+3)),STACK_0))
                    #endif
                    {
                     push_matching_subdir:
                      # Subdirectory matcht -> zu einem Pathname
                      # machen und auf new-pathname-list pushen:
                      pushSTACK(STACK_2); pushSTACK(STACK_(0+1)); # pathname und direntry
                      {
                        var object pathname = pathname_add_subdir();
                        pushSTACK(pathname);
                      }
                      # Diesen neuen Pathname vor new-pathname-list pushen:
                      {
                        var object new_cons = allocate_cons();
                        Car(new_cons) = popSTACK();
                        Cdr(new_cons) = STACK_(3+3);
                        STACK_(3+3) = new_cons;
                      }
                    }
                  }
                } else {
                  # Eintrag ist ein (halbwegs) normales File.
                  if (next_task>0) {
                    #ifndef RISCOS
                    # name&type mit direntry matchen:
                    if (wildcard_match(STACK_(2+4+3),STACK_0))
                    #endif
                    {
                     push_matching_file:
                      # File matcht -> zu einem Pathname machen
                      # und auf result-list pushen:
                      #ifndef PATHNAME_RISCOS
                      pushSTACK(STACK_0); # direntry
                      split_name_type(1); # in Name und Typ aufspalten
                      {
                        var object pathname = copy_pathname(STACK_(2+2));
                        ThePathname(pathname)->pathname_type = popSTACK(); # Typ einsetzen
                        ThePathname(pathname)->pathname_name = popSTACK(); # Name einsetzen
                        pushSTACK(pathname);
                        pushSTACK(pathname);
                      }
                      #else # PATHNAME_RISCOS
                      {
                        var object pathname = copy_pathname(STACK_2);
                        pushSTACK(pathname);
                        if (name_and_type && nullp(ThePathname(pathname)->pathname_type)) {
                          # Move the last subdir into the type slot of the pathname.
                          # subdirs := (butlast subdirs) = (nreverse (cdr (reverse subdirs)))
                          var object subdirs = reverse(ThePathname(pathname)->pathname_directory);
                          pathname = STACK_0;
                          ThePathname(pathname)->pathname_type = Car(subdirs);
                          ThePathname(pathname)->pathname_directory = nreverse(Cdr(subdirs));
                        }
                        ThePathname(pathname)->pathname_name = STACK_1; # direntry
                        pushSTACK(pathname);
                      }
                      #endif
                      # Truename bilden (symbolische Links auflösen):
                      assure_dir_exists(true,false);
                      if (file_exists(_EMA_)) { # falls File (immer noch...) existiert
                        if (!nullp(STACK_(0+5+4+3+2))) # :FULL gewünscht?
                          with_stat_info(); # ja -> STACK_0 erweitern
                        # und STACK_0 vor result-list pushen:
                        {
                          var object new_cons = allocate_cons();
                          Car(new_cons) = STACK_0;
                          Cdr(new_cons) = STACK_(4+4+3+2);
                          STACK_(4+4+3+2) = new_cons;
                        }
                      }
                      skipSTACK(2);
                    }
                  }
                }
              }
             done_direntry:
              skipSTACK(1); # direntry vergessen
            }
          }
          begin_system_call();
          if (CLOSEDIR(dirp)) { end_system_call(); OS_file_error(STACK_1); }
          end_system_call();
          clr_break_sem_4();
        }
      #endif
      #ifdef AMIGAOS
        # Directory absuchen:
        {
          var object namestring = OSdirnamestring(STACK_0);
          with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
            set_break_sem_4();
            begin_system_call();
            var BPTR lock = Lock(namestring_asciz,ACCESS_READ);
            var LONGALIGNTYPE(struct FileInfoBlock) fib;
            var struct FileInfoBlock * fibptr = LONGALIGN(&fib);
            if (lock==BPTR_NULL) {
              end_system_call(); OS_file_error(STACK_1);
             }
            if (! Examine(lock,fibptr) ) {
              UnLock(lock); end_system_call(); OS_file_error(STACK_1);
            }
            loop {
              if (! ExNext(lock,fibptr) ) # Error oder Directory zu Ende?
                break;
              end_system_call();
              # Directory-Eintrag in String umwandeln:
              var object direntry = asciz_to_string(&fibptr->fib_FileName[0],O(pathname_encoding));
              pushSTACK(direntry);
              # Stackaufbau: ..., pathname, dir_namestring, direntry.
              # Feststellen, ob es ein Directory oder ein File ist:
              {
                var bool isdir;
                if (fibptr->fib_DirEntryType == ST_SOFTLINK) {
                  # Einen Lock auf das Ziel holen und Examine ausführen:
                  # das geht, denn Lock() löst Links auf (bzw. versucht es)
                  pushSTACK(STACK_1); pushSTACK(STACK_(0+1));
                  var object direntry_namestring = string_concat(2);
                  with_sstring_0(direntry_namestring,O(pathname_encoding),direntry_namestring_asciz, {
                    begin_system_call();
                    # TODO olddir = CurrentDir(lock); ... CurrentDir(olddir)
                    var BPTR direntry_lock = Lock(direntry_namestring_asciz,ACCESS_READ);
                    if (direntry_lock==BPTR_NULL)
                      switch (IoErr()) {
                        case ERROR_OBJECT_NOT_FOUND:
                        case ERROR_DEVICE_NOT_MOUNTED: # user canceled requester
                          end_system_call();
                          FREE_DYNAMIC_ARRAY(direntry_namestring_asciz);
                          goto skip_direntry; # direntry vergessen und ignorieren
                        default:
                          end_system_call(); OS_file_error(STACK_2);
                      }
                    var LONGALIGNTYPE(struct FileInfoBlock) direntry_status;
                    var struct FileInfoBlock * statusptr = LONGALIGN(&direntry_status);
                    if (! Examine(direntry_lock,statusptr) ) {
                      UnLock(direntry_lock); end_system_call(); OS_file_error(STACK_2);
                    }
                    UnLock(direntry_lock);
                    end_system_call();
                    isdir = (statusptr->fib_DirEntryType >= 0);
                  });
                } else {
                  isdir = (fibptr->fib_DirEntryType >= 0);
                }
                if (isdir) {
                  # Eintrag ist ein Directory.
                  if (recursively) { # alle rekursiven Subdirectories gewünscht?
                    # ja -> zu einem Pathname machen und auf
                    # pathnames-to-insert pushen (wird nachher
                    # vor pathname-list-rest eingefügt):
                    pushSTACK(STACK_2); pushSTACK(STACK_(0+1)); # pathname und direntry
                    {
                      var object pathname = pathname_add_subdir();
                      pushSTACK(pathname);
                    }
                    # Diesen neuen Pathname vor pathname-to-insert pushen:
                    {
                      var object new_cons = allocate_cons();
                      Car(new_cons) = popSTACK();
                      Cdr(new_cons) = STACK_(0+3);
                      STACK_(0+3) = new_cons;
                    }
                  }
                  if (next_task<0) {
                    # (car subdir-list) mit direntry matchen:
                    if (wildcard_match(Car(STACK_(1+4+3)),STACK_0)) {
                      # Subdirectory matcht -> zu einem Pathname
                      # machen und auf new-pathname-list pushen:
                      pushSTACK(STACK_2); pushSTACK(STACK_(0+1)); # pathname und direntry
                      {
                        var object pathname = pathname_add_subdir();
                        pushSTACK(pathname);
                      }
                      # Diesen neuen Pathname vor new-pathname-list pushen:
                      {
                        var object new_cons = allocate_cons();
                        Car(new_cons) = popSTACK();
                        Cdr(new_cons) = STACK_(3+3);
                        STACK_(3+3) = new_cons;
                      }
                    }
                  }
                } else {
                  # Eintrag ist ein (halbwegs) normales File.
                  if (next_task>0) {
                    # name&type mit direntry matchen:
                    if (wildcard_match(STACK_(2+4+3),STACK_0)) {
                      # File matcht -> zu einem Pathname machen
                      # und auf result-list pushen:
                      pushSTACK(STACK_0); # direntry
                      split_name_type(1); # in Name und Typ aufspalten
                      {
                        var object pathname = copy_pathname(STACK_(2+2));
                        ThePathname(pathname)->pathname_type = popSTACK(); # Typ einsetzen
                        ThePathname(pathname)->pathname_name = popSTACK(); # Name einsetzen
                        pushSTACK(pathname);
                        pushSTACK(pathname);
                      }
                      assure_dir_exists(true,false); # Truename bilden (symbolische Links auflösen)
                      if (!nullp(STACK_(0+5+4+3+2))) # :FULL gewünscht?
                        with_stat_info(); # ja -> STACK_0 erweitern
                      # und STACK_0 vor result-list pushen:
                      {
                        var object new_cons = allocate_cons();
                        Car(new_cons) = STACK_0;
                        Cdr(new_cons) = STACK_(4+4+3+2);
                        STACK_(4+4+3+2) = new_cons;
                      }
                      skipSTACK(2);
                    }
                  }
                }
              }
             skip_direntry:
              skipSTACK(1); # direntry vergessen
              begin_system_call();
            }
            UnLock(lock);
            if (!(IoErr()==ERROR_NO_MORE_ENTRIES)) {
              end_system_call(); OS_file_error(STACK_1);
            }
            end_system_call();
            clr_break_sem_4();
          });
        }
      #endif
      #if defined(MSDOS) || defined(WIN32_NATIVE)
        {
          pushSTACK(STACK_0); # Directory-Name
          pushSTACK(READDIR_wildnametype_suffix); # und "*.*" bzw. "*"
          var object namestring = string_concat(2); # zusammenhängen
          with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
            # Directory absuchen, gemäß DOS-Konvention bzw. Win32-Konvention:
            READDIR_var_declarations;
            # Suchanfang, suche nach Ordnern und normalen Dateien:
            begin_system_call();
            do {
              READDIR_findfirst(namestring_asciz,
                                { end_system_call(); OS_file_error(STACK_1); },
                                break; );
              loop {
                end_system_call();
                # Directory-Eintrag in String umwandeln:
                var object direntry = asciz_to_string(READDIR_entry_name(),O(pathname_encoding));
                # "." und ".." übergehen:
                if (!(equal(direntry,O(punkt_string))
                      || equal(direntry,O(punktpunkt_string))
                   ) ) {
                  pushSTACK(direntry);
                  # Stackaufbau: ..., pathname, dir_namestring, direntry.
                  if (READDIR_entry_ISDIR()) { # Ist es ein Directory?
                    # Eintrag ist ein Directory.
                    if (recursively) { # alle rekursiven Subdirectories gewünscht?
                      # ja -> zu einem Pathname machen und auf
                      # pathnames-to-insert pushen (wird nachher
                      # vor pathname-list-rest eingefügt):
                      pushSTACK(STACK_2); pushSTACK(STACK_(0+1)); # pathname und direntry
                      {
                        var object pathname = pathname_add_subdir();
                        pushSTACK(pathname);
                      }
                      # Diesen neuen Pathname vor pathname-to-insert pushen:
                      {
                        var object new_cons = allocate_cons();
                        Car(new_cons) = popSTACK();
                        Cdr(new_cons) = STACK_(0+3);
                        STACK_(0+3) = new_cons;
                      }
                    }
                    if (next_task<0) {
                      # (car subdir-list) mit direntry matchen:
                      if (wildcard_match(Car(STACK_(1+4+3)),STACK_0)) {
                        # Subdirectory matcht -> zu einem Pathname
                        # machen und auf new-pathname-list pushen:
                        pushSTACK(STACK_2); pushSTACK(STACK_(0+1)); # pathname und direntry
                        {
                          var object pathname = pathname_add_subdir();
                          pushSTACK(pathname);
                        }
                        # Diesen neuen Pathname vor new-pathname-list pushen:
                        {
                          var object new_cons = allocate_cons();
                          Car(new_cons) = popSTACK();
                          Cdr(new_cons) = STACK_(3+3);
                          STACK_(3+3) = new_cons;
                        }
                      }
                    }
                  } else {
                    # Eintrag ist ein (halbwegs) normales File.
                    if (next_task>0) {
                      # name&type mit direntry matchen:
                      if (wildcard_match(STACK_(2+4+3),STACK_0)) {
                        # File matcht -> zu einem Pathname machen
                        # und auf result-list pushen:
                        pushSTACK(STACK_0); # direntry
                        split_name_type(1); # in Name und Typ aufspalten
                        {
                          var object new = copy_pathname(STACK_(2+2));
                          ThePathname(new)->pathname_type = popSTACK(); # Typ einsetzen
                          ThePathname(new)->pathname_name = popSTACK(); # Name einsetzen
                          # Full-Flag abtesten und evtl. mehr Information besorgen:
                          if (!nullp(STACK_(0+5+4+3))) { # :FULL gewünscht?
                            pushSTACK(new); # newpathname als 1. Listenelement
                            pushSTACK(new); # newpathname als 2. Listenelement
                            {
                              # Uhrzeit und Datum von DOS-Format in Decoded-Time umwandeln:
                              var decoded_time timepoint;
                              READDIR_entry_timedate(&timepoint);
                              pushSTACK(timepoint.Sekunden);
                              pushSTACK(timepoint.Minuten);
                              pushSTACK(timepoint.Stunden);
                              pushSTACK(timepoint.Tag);
                              pushSTACK(timepoint.Monat);
                              pushSTACK(timepoint.Jahr);
                              new = listof(6); # 6-elementige Liste bauen
                            }
                            pushSTACK(new); # als 3. Listenelement
                            pushSTACK(UL_to_I(READDIR_entry_size())); # Länge als 4. Listenelement
                            new = listof(4); # 4-elementige Liste bauen
                          }
                          pushSTACK(new);
                        }
                        # und STACK_0 vor result-list pushen:
                        {
                          var object new_cons = allocate_cons();
                          Car(new_cons) = popSTACK();
                          Cdr(new_cons) = STACK_(4+4+3);
                          STACK_(4+4+3) = new_cons;
                        }
                      }
                    }
                  }
                  skipSTACK(1); # direntry vergessen
                }
                # nächstes File:
                begin_system_call();
                READDIR_findnext({ end_system_call(); OS_file_error(STACK_1); }, break; );
              }
            } while (false);
            end_system_call();
            READDIR_end_declarations;
          });
        }
      #endif
    }
  #
  local object directory_search(pathname)
    var object pathname;
    {
      #ifdef PATHNAME_RISCOS
      # If we search for a file with type /= NIL, we have to interpret the last
      # subdir as the type.
      var bool name_and_type = false;
      # We need to remember if the type is wild, since this controls whether
      # found files are legal.
      var bool type_is_wild = false;
      #endif
      pathname = use_default_dir(pathname); # Default-Directory einfügen
      # pathname ist jetzt neu und ein absoluter Pathname.
      pushSTACK(NIL); # result-list := NIL
      pushSTACK(pathname);
      # Falls name=NIL und type/=NIL: Setze name := "*".
      if (nullp(ThePathname(pathname)->pathname_name)
          && !nullp(ThePathname(pathname)->pathname_type)
         )
        ThePathname(pathname)->pathname_name = O(wild_string);
      #ifdef PATHNAME_RISCOS
      # If the name and type are both set, then make the type part of
      # the directory specification and set the new type to NIL.
      if (!nullp(ThePathname(pathname)->pathname_name)
          && !nullp(ThePathname(pathname)->pathname_type)
         ) {
        name_and_type = true;
        type_is_wild = has_wildcards(ThePathname(pathname)->pathname_type);
        pushSTACK(pathname); pushSTACK(ThePathname(pathname)->pathname_type);
        STACK_0 = pathname = pathname_add_subdir();
        ThePathname(pathname)->pathname_type = NIL;
      }
      #endif
      # Zum Matchen: Name und Typ zu einem String zusammenfassen:
      if (nullp(ThePathname(pathname)->pathname_name)) {
        pushSTACK(NIL); # name=NIL -> auch type=NIL -> keine Files suchen
      } else {
        var object nametype_string = file_namestring(pathname);
        pathname = STACK_0;
        pushSTACK(nametype_string);
      }
      pushSTACK(ThePathname(pathname)->pathname_directory); # subdir-list
      #ifdef PATHNAME_RISCOS
      STACK_0 = Cdr(STACK_0); # Liste fängt mit (:ABSOLUTE :ROOT ...) an, verkürze sie
      #endif
      # pathname kopieren und dabei Name und Typ streichen und
      # Directory zu (:ABSOLUTE) bzw. (:ABSOLUTE :ROOT) verkürzen:
      pathname = copy_pathname(pathname);
      ThePathname(pathname)->pathname_name = NIL;
      ThePathname(pathname)->pathname_type = NIL;
      ThePathname(pathname)->pathname_directory = O(directory_absolute);
      pushSTACK(pathname);
      # und in einelementige Liste packen:
      {
        var object new_cons = allocate_cons();
        Car(new_cons) = STACK_0;
        STACK_0 = new_cons;
      }
      var bool recursively = # Flag, ob die nächste Operation auf
        false;                  # alle Subdirectories anzuwenden ist.
      loop {
        # Stackaufbau: result-list, pathname, name&type, subdir-list, pathname-list.
        # result-list = Liste der fertigen Pathnames/Listen, umgedreht.
        # name&type = NIL oder Normal-Simple-String, gegen den die Filenamen zu matchen sind.
        # pathname-list = Liste der noch abzuarbeitenden Directories.
        # Dabei enthalten die Pathnames aus pathname-list das Directory
        # nur so tief, dass es danach mit (cdr subdir-list) weitergeht.
        # Nächste subdir-Ebene abarbeiten:
        STACK_1 = Cdr(STACK_1); # subdir-list verkürzen
        var signean next_task; # Was mit den Dirs aus pathname-list zu tun ist:
          # 0: nichts, fertig
          # 1: nach einem File gegebenen Namens/Typs sehen
          # -1: nach einem Subdirectory gegebenen Namens sehen
          # 2: nach allen Files suchen, die gegebenen Namen/Typ matchen
          # -2: nach allen Subdirectories suchen, die gegebenen Namen matchen
        if (matomp(STACK_1)) { # subdir-list zu Ende?
          var object nametype = STACK_2;
          if (nullp(nametype)) # name=NIL und type=NIL -> keine Files suchen
            next_task = 0;
          #if !(defined(MSDOS) || defined(WIN32_NATIVE))
          elif (!has_wildcards(nametype))
               # === !(has_wildcards(name) || ((!nullp(type)) && has_wildcards(type)))
            next_task = 1; # File suchen
          #endif
          else
            next_task = 2; # Files mit Wildcards suchen
        } else {
          var object next_subdir = Car(STACK_1);
          if (eq(next_subdir,S(Kwild_inferiors))) { # '...' ?
            # wird erst beim nächsten Durchlauf behandelt
            recursively = true; goto passed_subdir;
          }
          #ifndef MSDOS
          if (
              #ifdef PATHNAME_AMIGAOS
              eq(next_subdir,S(Kparent)) ||
              #endif
              #ifdef PATHNAME_RISCOS
              !simple_string_p(next_subdir) ||
              #endif
              !has_wildcards(next_subdir)
             )
            next_task = -1; # Subdir suchen
          else
          #endif
            next_task = -2; # Subdirs mit Wildcards suchen
        }
        # pathname-list durchgehen und dabei neue Liste aufbauen:
        pushSTACK(NIL);
        #ifdef UNIX
        if (!nullp(STACK_(1+5+1))) { # :CIRCLE-Flag abfragen
          # Hash-Tabelle aller bisher abgesuchten Directories (jeweils
          # als Cons (dev . ino)) führen:
          pushSTACK(S(Ktest)); pushSTACK(S(equal));
          funcall(L(make_hash_table),2); # (MAKE-HASH-TABLE :TEST 'EQUAL)
          pushSTACK(value1);
        } else
        #endif
          pushSTACK(NIL);
        pushSTACK(STACK_(0+2));
        loop {
          # Stackaufbau: ..., new-pathname-list, ht, pathname-list-rest.
          var object pathname_list_rest = STACK_0;
          if (atomp(pathname_list_rest))
            break;
          STACK_0 = Cdr(pathname_list_rest); # Liste verkürzen
          pushSTACK(NIL); # pathnames-to-insert := NIL
          # Stackaufbau: ..., new-pathname-list, ht, pathname-list-rest, pathnames-to-insert.
          {
            var object pathname = Car(pathname_list_rest); # nächstes Directory
            pushSTACK(pathname); # in den Stack
            # Versuche, die Task ein wenig abzukürzen:
            if (!recursively) {
              switch (next_task) {
                case 0: # Dieses pathname liefern
                  #ifdef UNIX
                  assure_dir_exists(false,false); # erst noch Links auflösen
                  #endif
                  # und STACK_0 vor result-list pushen:
                  {
                    var object new_cons = allocate_cons();
                    Car(new_cons) = popSTACK();
                    Cdr(new_cons) = STACK_(4+4);
                    STACK_(4+4) = new_cons;
                  }
                  goto next_pathname;
                #if !(defined(MSDOS) || defined(WIN32_NATIVE))
                case 1: # In diesem pathname nach einem File sehen
                  ThePathname(pathname)->pathname_name = # Name (/=NIL) einsetzen
                  ThePathname(STACK_(3+4+1))->pathname_name;
                  ThePathname(pathname)->pathname_type = # Typ einsetzen
                  ThePathname(STACK_(3+4+1))->pathname_type;
                  pushSTACK(pathname);
                  #ifdef PATHNAME_RISCOS
                  if (name_and_type && nullp(ThePathname(pathname)->pathname_type)) {
                    # Move the last subdir into the type slot of the pathname.
                    # subdirs := (butlast subdirs) = (nreverse (cdr (reverse subdirs)))
                    var object subdirs = reverse(ThePathname(pathname)->pathname_directory);
                    pathname = STACK_0;
                    ThePathname(pathname)->pathname_type = Car(subdirs);
                    ThePathname(pathname)->pathname_directory = nreverse(Cdr(subdirs));
                  }
                  assure_dir_exists_(true,false,type_is_wild); # Links auflösen, File suchen
                  if (file_exists(_EMA_) && !S_ISDIR(filestatus->st_mode)) # falls File existiert und kein Directory ist
                  #else
                  assure_dir_exists(true,false); # Links auflösen, File suchen
                  if (file_exists(_EMA_)) # falls File existiert
                  #endif
                  {
                    # result-list erweitern:
                    if (!nullp(STACK_(0+5+4+2))) # :FULL gewünscht?
                      with_stat_info(); # ja -> STACK_0 erweitern
                    # und STACK_0 vor result-list pushen:
                    var object new_cons = allocate_cons();
                    Car(new_cons) = STACK_0;
                    Cdr(new_cons) = STACK_(4+4+2);
                    STACK_(4+4+2) = new_cons;
                  }
                  skipSTACK(2);
                  goto next_pathname;
                #endif
                #ifndef MSDOS
                case -1: # In diesem pathname nach einem Subdirectory sehen
                  {
                    var object namestring = assure_dir_exists(true,false); # Links auflösen, Directory-Namestring
                    pushSTACK(namestring); # Directory-Namestring
                    {
                      var object subdir = Car(STACK_(1+4+1+1)); # (car subdir-list)
                      #if defined(PATHNAME_AMIGAOS) || defined(PATHNAME_RISCOS)
                      if (eq(subdir,S(Kparent))) { # für Parent-Directory
                        #ifdef PATHNAME_AMIGAOS
                        pushSTACK(O(slash_string)); # zusätzliches "/" ans Ende
                        #endif
                        #ifdef PATHNAME_RISCOS
                        pushSTACK(O(parent_string)); # zusätzliches "^" ans Ende
                        #endif
                      } else
                      #endif
                        pushSTACK(subdir);
                    }
                    namestring = string_concat(2); # zusammenhängen
                    # Information holen:
                    directory_search_1subdir(Car(STACK_(1+4+1)),namestring);
                  }
                  skipSTACK(1);
                  goto next_pathname;
                #endif
              }
            }
            # Um die Task zu erledigen, müssen alle Einträge dieses
            # Directory abgesucht werden:
            {
              var object dir_namestring = assure_dir_exists(true,false); # Links auflösen, Directory-Name bilden
              pushSTACK(dir_namestring); # retten
            }
            # Stackaufbau: ..., pathname, dir_namestring.
            #ifdef UNIX
            if (!nullp(STACK_(1+5+4+2))) { # :CIRCLE-Flag abfragen
              # pathname in der Hash-Tabelle suchen:
              var object hashcode = directory_search_hashcode();
              if (eq(hashcode,nullobj)) {
                # Eintrag existiert doch nicht (das kann uns
                # wohl nur bei symbolischen Links passieren)
                # -> wird übergangen
                skipSTACK(2); goto next_pathname;
              }
              # und in der Hash-Tabelle aufsuchen und ablegen:
              if (!nullp(shifthash(STACK_(2+2),hashcode,T))) {
                # war schon drin -> wird übergangen
                skipSTACK(2); goto next_pathname;
              }
            }
            #endif
            if (next_task==0) {
              # Pathname STACK_1 vor result-list pushen:
              var object new_cons = allocate_cons();
              Car(new_cons) = STACK_1;
              Cdr(new_cons) = STACK_(4+4+2);
              STACK_(4+4+2) = new_cons;
            }
            directory_search_scandir(recursively,next_task);
            skipSTACK(2); # pathname und dir_namestring vergessen
            next_pathname: ;
          }
          # Stackaufbau: ..., new-pathname-list, ht, pathname-list-rest, pathnames-to-insert.
          # Vor dem Weiterrücken mit pathname-list-rest :
          # pathname-list-rest := (nreconc pathnames-to-insert pathname-list-rest) :
          var object pathnames_to_insert = popSTACK();
          STACK_0 = nreconc(pathnames_to_insert,STACK_0);
        }
        skipSTACK(2); # leere pathname-list-rest und Hash-Tabelle vergessen
        # new-pathname-list umdrehen, ersetzt die geleerte pathname-list:
        {
          var object new_pathname_list = popSTACK();
          STACK_0 = nreverse(new_pathname_list); # neue pathname-list
        }
        # Mit dieser Subdir-Stufe sind wir fertig.
        if (matomp(STACK_1))
          break; # (atom subdir-list) -> fertig.
        recursively = false; # die nächste (vorläufig) nicht-rekursiv
        passed_subdir: ;
      }
      # Stackaufbau: result-list, pathname, name&type, subdir-list, pathname-list.
      # subdir-list ist =NIL geworden, auch pathname-list = NIL (denn beim
      # letzten Schleifendurchlauf ist immer next_task=0,1,2, und dadurch
      # wurde nichts auf new-pathname-list gepusht).
      skipSTACK(4);
      return popSTACK(); # result-list als Ergebnis
    }
  #
  #endif # PATHNAME_NOEXT

LISPFUN(directory,0,1,norest,key,2, (kw(circle),kw(full)) )
# (DIRECTORY [pathname [:circle] [:full]]), CLTL S. 427
  {
    # Stackaufbau: pathname, circle, full.
    #ifdef UNIX
    # :CIRCLE-Argument hat Defaultwert NIL:
    if (eq(STACK_1,unbound))
      STACK_1 = NIL;
    #endif
    # :FULL-Argument hat Defaultwert NIL:
    if (eq(STACK_0,unbound))
      STACK_0 = NIL;
    # Pathname-Argument überprüfen:
    var object pathname = STACK_2;
    if (eq(pathname,unbound)) {
      #if defined(PATHNAME_NOEXT) || defined(PATHNAME_RISCOS)
      pathname = O(wild_string); # Default ist "*"
      #endif
    }
    pathname = coerce_pathname(pathname); # zu einem Pathname machen
    # Los geht's:
    #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
    if (eq(ThePathname(pathname)->pathname_device,S(Kwild))) { # Device = :WILD ?
      # alle Devices abzusuchen
      STACK_2 = pathname;
      pushSTACK(NIL); # bisherige Pathname-Liste := NIL
      pushSTACK(STACK_(0+1)); # full (für directory_search)
      # Stackaufbau: pathname, circle, full, pathname-list, full.
      {
        var char drive;
        for (drive='A'; drive<='Z'; drive++) # alle Drives durchlaufen
          if (good_drive(drive)) {
            pushSTACK(n_char_to_string(&drive,1,O(pathname_encoding))); # Device, einelementiger String
            var object newpathname = copy_pathname(STACK_(2+2+1)); # Pathname kopieren
            ThePathname(newpathname)->pathname_device = popSTACK(); # Drive übernehmen
            # innerhalb eines Laufwerks suchen:
            var object newpathnames = directory_search(newpathname);
            # und Pathname-Liste vor STACK_1 hängen:
            STACK_1 = nreconc(newpathnames,STACK_1);
          }
      }
      value1 = nreverse(STACK_1); # Pathname-Liste wieder umdrehen
      skipSTACK(3+2);
    } else
      # nur ein Device abzusuchen
    #endif
    {
      value1 = directory_search(pathname); # matchende Pathnames bilden
      skipSTACK(3);
    }
    mv_count=1;
  }

LISPFUN(cd,0,1,norest,nokey,0,NIL)
# (CD [pathname]) setzt das aktuelle Laufwerk und das aktuelle Directory.
  {
    var object pathname = popSTACK();
    if (eq(pathname,unbound)) { pathname = O(leer_string); } # "" als Default
    pathname = coerce_pathname(pathname); # zu einem Pathname machen
    # kopieren und Name und Typ auf NIL setzen:
    pathname = copy_pathname(pathname);
    ThePathname(pathname)->pathname_name = NIL;
    ThePathname(pathname)->pathname_type = NIL;
    check_no_wildcards(pathname); # mit Wildcards -> Fehler
    pathname = use_default_dir(pathname); # absoluten Pathname draus machen
    pushSTACK(pathname);
    assure_dir_exists(false,false); # Directory muss existieren
    #if HAS_HOST # necessary at least for PATHNAME_WIN32
    if (!nullp(ThePathname(STACK_0)->pathname_host)) {
      pushSTACK(STACK_0); # value for slot PATHNAME of FILE-ERROR
      pushSTACK(STACK_(0+1));
      pushSTACK(TheSubr(subr_self)->name);
      fehler(file_error,
             GETTEXT("~: cannot change default directory on remote host: ~")
            );
    }
    #endif
    change_default(); # Default-Drive, Default-Directory setzen
    value1 = popSTACK(); mv_count=1; # neuer pathname als Wert
  }

# UP: Überprüft ein Pathname, ob Name und Typ beide =NIL sind,
# und ob das Directory "fast" existiert.
# shorter_directory(pathname,resolve_links)
# > pathname : Pathname-Argument
# > resolve_links : Flag, ob Links aufgelöst werden müssen (normalerweise ja)
# < -(STACK) : absoluter Pathname
#if defined(MSDOS) || defined(WIN32_NATIVE)
# < ergebnis: Directory-Namestring (fürs OS, ohne '\' am Schluss, Normal-Simple-String)
#endif
#if defined(UNIX) || defined(AMIGAOS)
# < ergebnis: Directory-Namestring (fürs OS, ohne '/' am Schluss, Normal-Simple-String)
#endif
#if defined(RISCOS)
# < ergebnis: Directory-Namestring (fürs OS, ohne '.' am Schluss, Normal-Simple-String)
#endif
# Erniedrigt STACK um 1.
# can trigger GC
  local object shorter_directory (object pathname, bool resolve_links);
  local object shorter_directory(pathname,resolve_links)
    var object pathname;
    var bool resolve_links;
    {
      pathname = coerce_pathname(pathname); # Argument zu einem Pathname machen
      check_no_wildcards(pathname); # mit Wildcards -> Fehler
      pathname = use_default_dir(pathname); # Default-Directory einfügen
      # Überprüfe, ob Name=NIL und Typ=NIL :
      if (!(nullp(ThePathname(pathname)->pathname_name)
            && nullp(ThePathname(pathname)->pathname_type)
         ) )
        fehler_notdir(pathname);
      pushSTACK(pathname); # neuen Pathname retten
      # verkürze das Directory:
      var object subdirs = ThePathname(pathname)->pathname_directory;
      if (nullp(Cdr(subdirs))) { # Root-Directory ?
       baddir:
        # STACK_0 = pathname, Wert für Slot PATHNAME von FILE-ERROR
        pushSTACK(STACK_0);
        fehler(file_error,
               GETTEXT("root directory not allowed here: ~")
              );
      }
      subdirs = reverse(subdirs); # Liste kopieren und dabei umdrehen
      #if defined(PATHNAME_AMIGAOS) || defined(PATHNAME_RISCOS)
      if (eq(Car(subdirs),S(Kparent))) # letztes Subdir muss /= :PARENT sein
        goto baddir;
      #endif
      pushSTACK(subdirs); # Cons mit letztem Subdir als CAR retten
      subdirs = Cdr(subdirs); # alle Subdirs bis aufs letzte
      subdirs = nreverse(subdirs); # wieder in die richtige Reihenfolge bringen
      pathname = STACK_1;
      ThePathname(pathname)->pathname_directory = subdirs; # und in den Pathname setzen
      # Dieses Directory muss existieren:
      pushSTACK(pathname);
      # Stackaufbau: pathname, subdircons, pathname.
      var object dir_namestring =
        (resolve_links ? assure_dir_exists(false,false) : assume_dir_exists());
      # Baue Subdir-String fürs Betriebssystem:
      STACK_0 = dir_namestring; # bisheriger Directory-Namestring als 1. String
      var uintC stringcount =
        subdir_namestring_parts(STACK_1); # und Strings zum letzten Subdir
      # und kein '\' am Schluss (fürs OS)
      # und kein '/' am Schluss (fürs OS)
      var object dirstring = string_concat(1+stringcount); # zusammenhängen
      skipSTACK(1);
      return dirstring;
    }

LISPFUNN(make_dir,1)
# (MAKE-DIR pathname) legt ein neues Unterdirectory pathname an.
  {
    var object pathstring = shorter_directory(STACK_0,true);
    with_sstring_0(pathstring,O(pathname_encoding),pathstring_asciz, {
      make_directory(pathstring_asciz);
    });
    skipSTACK(2);
    value1 = T; mv_count=1; # 1 Wert T
  }

LISPFUNN(delete_dir,1)
# (DELETE-DIR pathname) entfernt das Unterdirectory pathname.
  {
    var object pathstring = shorter_directory(STACK_0,true);
    with_sstring_0(pathstring,O(pathname_encoding),pathstring_asciz, {
      delete_directory(pathstring_asciz);
    });
    skipSTACK(2);
    value1 = T; mv_count=1; # 1 Wert T
  }

LISPFUN(ensure_directories_exist,1,0,norest,key,1,(kw(verbose)))
# (defun ensure-directories-exist (pathspec &key verbose)
#   (let* ((dir (pathname-directory pathspec))
#          (path (make-pathname :host (pathname-host pathspec)
#                               :device (pathname-device pathspec)
#                               :directory dir)))
#     (when (wild-pathname-p path)
#       (error (make-condition 'file-error :pathname pathspec)))
#     (if (directory path)
#       (values pathspec nil)
#       (progn
#         (loop
#           for i from 1 upto (length dir)
#           do (let ((newpath
#                      (make-pathname :host (pathname-host pathspec)
#                                     :device (pathname-device pathspec)
#                                     :directory (subseq dir 0 i))))
#                (unless (directory newpath)
#                  (let ((namestring (namestring newpath)))
#                    (when verbose
#                      (format *standard-output* "~&Creating directory: ~A~%"
#                              namestring))
#                    (ignore-errors (lisp:make-dir namestring))
#                    (unless (directory newpath)
#                      (error (make-condition 'file-error :pathname pathspec))
#              ) ) ) )
#         )
#         (values pathspec t)
# ) ) ) )
  {
    var object pathname = coerce_pathname(STACK_1); # Argument zu einem Pathname machen
    pathname = copy_pathname(pathname); # Kopieren und dabei name, type streichen
    ThePathname(pathname)->pathname_name = NIL;
    ThePathname(pathname)->pathname_type = NIL;
    check_no_wildcards(pathname); # mit Wildcards -> Fehler
    pathname = use_default_dir(pathname); # Default-Directory einfügen
    pushSTACK(pathname); # neuen Pathname retten
    # Stackaufbau: pathspec, verbose, pathname.
    if (directory_exists(pathname)) {
      skipSTACK(2); value2 = NIL; # pathspec, NIL als Werte
    } else {
      var object subdirs = copy_list(ThePathname(STACK_0)->pathname_directory);
      pushSTACK(subdirs); pushSTACK(Cdr(subdirs));
      Cdr(subdirs) = NIL;
      ThePathname(STACK_2)->pathname_directory = subdirs;
      # Stackaufbau: pathspec, verbose, pathname, (car (last subdirs)), remaining_subdirs.
      while (mconsp(STACK_0)) {
        subdirs = STACK_0;
        Cdr(STACK_1) = subdirs; STACK_1 = subdirs; STACK_0 = Cdr(subdirs); Cdr(subdirs) = NIL;
        if (!directory_exists(STACK_2)) {
          if (!eq(STACK_3,unbound) && !nullp(STACK_3)) { # Verbose?
            funcall(L(fresh_line),0); # (FRESH-LINE [*standard-output*])
            pushSTACK(OLS(mkdirp_string)); funcall(L(write_string),1); # (WRITE-STRING "..." [*standard-output*])
            pushSTACK(STACK_2); funcall(L(princ),1); # (PRINC pathname [*standard-output*])
            funcall(L(terpri),0); # (TERPRI [*standard-output*])
          }
          # NB: Brauche hier keine Links aufzulösen, weil man ja hier
          # sowieso ab der Wurzel schrittweise vorgeht.
          var object pathstring = shorter_directory(STACK_2,false);
          with_sstring_0(pathstring,O(pathname_encoding),pathstring_asciz, {
            make_directory(pathstring_asciz);
          });
          skipSTACK(1);
        }
      }
      skipSTACK(4); value2 = T; # pathspec, T als Werte
    }
    value1 = popSTACK(); mv_count=2;
  }

#ifdef UNIX
# Returns the struct passwd entry for the current user.
# The return value points to static data, or is NULL upon failure.
local struct passwd * unix_user_pwd (void);
local struct passwd * unix_user_pwd()
  {
    var const char* username;
    var struct passwd * userpasswd = NULL;
    # The manpage for GETLOGIN(3V) recommends
    # first getpwnam(getlogin()), then getpwuid(getuid()).
    begin_system_call();
    # 1. attempt: getpwnam(getenv("USER"))
    username = getenv("USER");
    if (username != NULL) {
      errno = 0; userpasswd = getpwnam(username);
      if (userpasswd != NULL) goto ok;
      if (errno != 0) { OS_error(); }
    }
    # 2. attempt: getpwnam(getlogin())
    username = getlogin();
    if (username != NULL) {
      errno = 0; userpasswd = getpwnam(username);
      if (userpasswd != NULL) goto ok;
      if (errno != 0) { OS_error(); }
    }
    # 3. attempt: getpwuid(getuid())
    errno = 0; userpasswd = getpwuid(user_uid);
    if (userpasswd != NULL) goto ok;
    if (errno != 0) { OS_error(); }
    # Everything fails, userpasswd == NULL.
   ok:
    end_system_call();
    return userpasswd;
  }
#endif

# UP: Initialisiert das Pathname-System.
# init_pathnames();
# can trigger GC
  global void init_pathnames (void);
  global void init_pathnames()
    {
      #if defined(PATHNAME_OS2) || defined(PATHNAME_WIN32)
      {
        # Default-Drive initialisieren:
        var char drive = default_drive();
        O(default_drive) = n_char_to_string(&drive,1,O(pathname_encoding));
      }
      #endif
      # *DEFAULT-PATHNAME-DEFAULTS* initialisieren:
      recalc_defaults_pathname();
      #ifdef USER_HOMEDIR
      #ifdef UNIX
      # Wir ziehen uns das Home-Directory und die benutzbare Shell aus dem
      # Environment. Es enthält (fast) immer mindestens folgende Variablen:
      #   LOGNAME = Username beim ersten Einloggen ("wahre" Identität des Benutzers)
      #   USER    = aktueller Username
      #   HOME    = aktuelles Home-Directory, aus /etc/passwd geholt
      #   SHELL   = aktuelle Standard-Shell, aus /etc/passwd geholt
      #   PATH    = Suchpfad bei Programmaufruf
      #   TERM    = Terminalemulation
      # Wir holen uns HOME (für "~" - Übersetzung) und SHELL (für EXECUTE).
      # Bei "~username" müssen wir das /etc/passwd - File absuchen.
      {
        # Im Environment nach Variable HOME suchen:
        begin_system_call();
        var const char* homedir = getenv("HOME");
        end_system_call();
        if (!(homedir==NULL)) { # gefunden?
          O(user_homedir) = asciz_dir_to_pathname(homedir,O(misc_encoding)); # ja -> eintragen
        } else {
          # nein -> Home-Directory aus dem Passwort-File holen:
          var struct passwd * userpasswd = unix_user_pwd();
          if (!(userpasswd==NULL)) {
            # ja -> Homedir als Pathname eintragen
            O(user_homedir) = asciz_dir_to_pathname(userpasswd->pw_dir,O(misc_encoding));
          } else {
            # nein -> aktuelles Directory nehmen:
            O(user_homedir) = default_directory();
          }
        }
      }
      #endif
      #ifdef WIN32
      # WinNT defines HOMEDRIVE and HOMEPATH. Win95 (which is actually not a
      # multiuser OS) lets the user set HOME himself.
      # In any case, we give preference to HOME, because the user can change
      # this.
      {
        var const char * home;
        begin_system_call();
        home = getenv("HOME");
        if (!(home==NULL)) {
          end_system_call();
          O(user_homedir) = asciz_dir_to_pathname(home,O(misc_encoding));
        } else {
          var const char * homedrive = getenv("HOMEDRIVE");
          var const char * homepath = getenv("HOMEPATH");
          end_system_call();
          if (homedrive!=NULL && homepath!=NULL) {
            var char* homeall = (char*)alloca(asciz_length(homedrive)+asciz_length(homepath)+1);
            var char* ptr = homeall;
            while ((*ptr = *homedrive) != '\0') { homedrive++; ptr++; }
            while ((*ptr = *homepath) != '\0') { homepath++; ptr++; }
            *ptr = '\0';
            O(user_homedir) = asciz_dir_to_pathname(homeall,O(misc_encoding));
          } else {
            O(user_homedir) = use_default_dir(asciz_dir_to_pathname(".",Symbol_value(S(ascii))));
          }
        }
      }
      #endif
      #endif
      #ifdef HAVE_SHELL
      #ifdef UNIX
      # Die Kommando-Shell O(command_shell) bleibt unverändert, sonst
      # handelt man sich zu viele Portabilitätsprobleme ein.
      {
        # Im Environment nach Variable SHELL suchen:
        begin_system_call();
        var const char* shell = getenv("SHELL");
        end_system_call();
        if (!(shell==NULL)) { # gefunden?
          O(user_shell) = asciz_to_string(shell,O(misc_encoding)); # ja -> eintragen
        }
        # sonst bleibt O(user_shell) auf dem Defaultwert "/bin/csh".
      }
      #endif
      #ifdef MSDOS
      {
        # Im Environment nach Variable COMSPEC suchen:
        begin_system_call();
        var const char* shell = getenv("COMSPEC");
        end_system_call();
        if (!(shell==NULL)) { # gefunden?
          O(command_shell) = asciz_to_string(shell,O(misc_encoding)); # ja -> eintragen
        }
        # sonst bleibt O(command_shell) auf dem Defaultwert "\\COMMAND.COM".
      }
      #endif
      #ifdef WIN32_NATIVE
      {
        # Im Environment nach Variable COMSPEC suchen:
        begin_system_call();
        var const char* shell = getenv("COMSPEC");
        if (!(shell==NULL)) {
          end_system_call();
          O(command_shell) = asciz_to_string(shell,O(misc_encoding)); # eintragen
        } else {
          var OSVERSIONINFO v;
          v.dwOSVersionInfoSize = sizeof(OSVERSIONINFO);
          if (!GetVersionEx(&v)) { OS_error(); }
          if (v.dwPlatformId == VER_PLATFORM_WIN32_NT) {
            # Windows NT
            shell = "cmd.exe";
          } else {
            # Windows 95 or else
            shell = "command.com";
          }
          end_system_call();
          O(command_shell) = ascii_to_string(shell); # eintragen
        }
      }
      #endif
      #endif
    }

LISPFUNN(file_write_date,1)
# (FILE-WRITE-DATE file), CLTL S. 424
  {
    #ifdef AMIGAOS
    var struct DateStamp file_datetime; # Buffer für Datum/Uhrzeit einer Datei
    #endif
    #if defined(UNIX) || defined(EMUNIX) || defined(RISCOS)
    var time_t file_datetime; # Buffer für Datum/Uhrzeit einer Datei
    #endif
    #ifdef WIN32_NATIVE
    var WIN32_FIND_DATA filedata;
    #endif
    var object pathname = popSTACK(); # pathname-Argument
    if (builtin_stream_p(pathname)) {
      # Stream -> extra behandeln:
      # muss File-Stream sein:
      pathname = as_file_stream(pathname);
      # Streamtyp File-Stream
      #if !defined(AMIGAOS)
      if ((TheStream(pathname)->strmflags & strmflags_open_B)
          && (!nullp(TheStream(pathname)->strm_buffered_channel))
         ) {
        # offener File-Stream
        # direkt mit dem Handle arbeiten:
        #if defined(UNIX) || defined(EMUNIX) || defined(RISCOS)
        var struct stat status;
        begin_system_call();
        if (!( fstat(TheHandle(TheStream(pathname)->strm_buffered_channel),&status) ==0)) {
          end_system_call(); OS_filestream_error(pathname);
        }
        end_system_call();
        file_datetime = status.st_mtime;
        #endif
        #ifdef WIN32_NATIVE
        var BY_HANDLE_FILE_INFORMATION fileinfo;
        var BOOL result;
        begin_system_call();
        result = GetFileInformationByHandle(TheHandle(TheStream(pathname)->strm_buffered_channel),&fileinfo);
        end_system_call();
        if (result) {
          filedata.ftCreationTime   = fileinfo.ftCreationTime;
          filedata.ftLastAccessTime = fileinfo.ftLastAccessTime;
          filedata.ftLastWriteTime  = fileinfo.ftLastWriteTime;
        } else {
          # If that failed, try the full pathname.
          test_file_stream_named(pathname);
          pathname = TheStream(pathname)->strm_file_truename;
          goto is_pathname;
        }
        #endif
      } else
      #endif
      {
        # geschlossener File-Stream -> Truename als Pathname verwenden
        test_file_stream_named(pathname);
        pathname = TheStream(pathname)->strm_file_truename;
        goto is_pathname;
      }
    } else {
      pathname = coerce_pathname(pathname); # zu einem Pathname machen
     is_pathname: # pathname ist jetzt wirklich ein Pathname
      check_no_wildcards(pathname); # mit Wildcards -> Fehler
      pathname = use_default_dir(pathname); # Default-Directory einfügen
      if (namenullp(pathname)) { fehler_noname(pathname); } # Kein Name angegeben -> Fehler
      # Name angegeben.
      pushSTACK(pathname);
      # Directory muss existieren:
      var object namestring = assure_dir_exists(false,false); # Filename fürs Betriebssystem
      #ifdef EMUNIX
        with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
          var struct stat statbuf;
          begin_system_call();
          if (stat(namestring_asciz,&statbuf) < 0) {
            end_system_call(); OS_file_error(STACK_0);
          }
          end_system_call();
          if (!S_ISREG(statbuf.st_mode)) { fehler_file_not_exists(); } # Datei muss existieren
          file_datetime = statbuf.st_mtime;
        });
      #endif
      #ifdef AMIGAOS
      if (!file_exists(namestring)) { fehler_file_not_exists(); } # Datei muss existieren
      file_datetime = filestatus->fib_Date;
      #endif
      #if defined(UNIX) || defined(RISCOS)
      if (!file_exists(namestring)) { fehler_file_not_exists(); } # Datei muss existieren
      file_datetime = filestatus->st_mtime;
      #endif
      #ifdef WIN32_NATIVE
      # Only a directory search gives us the times.
      with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
        var HANDLE search_handle;
        begin_system_call();
        search_handle = FindFirstFile(namestring_asciz,&filedata);
        if (search_handle==INVALID_HANDLE_VALUE) {
          if (GetLastError()==ERROR_FILE_NOT_FOUND || GetLastError()==ERROR_PATH_NOT_FOUND || GetLastError()==ERROR_BAD_NETPATH) {
            end_system_call(); fehler_file_not_exists();
          }
          end_system_call(); OS_file_error(STACK_0);
        } elif (!FindClose(search_handle)) {
          end_system_call(); OS_file_error(STACK_0);
        }
        end_system_call();
      });
      #endif
      skipSTACK(1);
    }
    # Datum/Uhrzeit steht nun im Buffer file_datetime.
    # In Universal-Time-Format umwandeln:
    #if defined(UNIX) || defined(EMUNIX) || defined(AMIGAOS) || defined(RISCOS)
    value1 = convert_time_to_universal(&file_datetime);
    #endif
    #ifdef WIN32_NATIVE
    var FILETIME* pftimepoint = &filedata.ftLastWriteTime;
    if (pftimepoint->dwLowDateTime==0 && pftimepoint->dwHighDateTime==0)
      pftimepoint = &filedata.ftCreationTime;
    value1 = convert_time_to_universal(pftimepoint);
    #endif
    mv_count=1;
  }

LISPFUNN(file_author,1)
# (FILE-AUTHOR file), CLTL S. 424
  {
    var object pathname = popSTACK(); # pathname-Argument
    if (builtin_stream_p(pathname)) {
      # Stream -> extra behandeln:
      # muss File-Stream sein:
      pathname = as_file_stream(pathname);
      # Streamtyp File-Stream
      if (TheStream(pathname)->strmflags & strmflags_open_B) {
        # offener File-Stream -> OK
      } else {
        # geschlossener File-Stream -> Truename als Pathname verwenden
        test_file_stream_named(pathname);
        pathname = TheStream(pathname)->strm_file_truename;
        goto is_pathname;
      }
    } else {
      pathname = coerce_pathname(pathname); # zu einem Pathname machen
     is_pathname: # pathname ist jetzt wirklich ein Pathname
      # pathname ist jetzt ein Pathname.
      check_no_wildcards(pathname); # mit Wildcards -> Fehler
      pathname = use_default_dir(pathname); # Default-Directory einfügen
      if (namenullp(pathname)) { fehler_noname(pathname); } # Kein Name angegeben -> Fehler
      # Name angegeben.
      pushSTACK(pathname);
      # Directory muss existieren:
      var object namestring = assure_dir_exists(false,false); # Filename fürs Betriebssystem
      #ifdef MSDOS
        #if 1
          with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
            # Datei öffnen:
            begin_system_call();
            var sintW ergebnis = # Datei zu öffnen versuchen
              open(namestring_asciz,O_RDONLY);
            if (ergebnis < 0) {
              end_system_call(); OS_file_error(STACK_0); # Error melden
            }
            # Nun enthält ergebnis das Handle des geöffneten Files.
            if (CLOSE(ergebnis) < 0) { # Datei gleich wieder schließen
              end_system_call(); OS_file_error(STACK_0);
            }
            end_system_call();
          });
        #else
          with_sstring_0(namestring,O(pathname_encoding),namestring_asciz, {
            var struct stat statbuf;
            begin_system_call();
            if (stat(namestring_asciz,&statbuf) < 0) {
              end_system_call(); OS_file_error(STACK_0);
            }
            end_system_call();
            if (!S_ISREG(statbuf.st_mode)) { fehler_file_not_exists(); } # Datei muss existieren
          });
        #endif
      #endif
      #if defined(UNIX) || defined(AMIGAOS) || defined(RISCOS) || defined(WIN32_NATIVE)
      if (!file_exists(namestring)) { fehler_file_not_exists(); } # Datei muss existieren
      #endif
      skipSTACK(1);
    }
    # Datei existiert -> NIL als Wert
    value1 = NIL; mv_count=1;
  }

#if defined(UNIX) || defined(MSDOS) || defined(RISCOS)

LISPFUN(execute,1,0,rest,nokey,0,NIL)
# (EXECUTE file arg1 arg2 ...) ruft ein File mit gegebenen Argumenten auf.
  {
    var object* args_pointer = rest_args_pointer STACKop 1;
    {
      var object* argptr = args_pointer; # Pointer über die Argumente
      # File überprüfen:
      {
        var object* file_ = &NEXT(argptr);
        var object pathname = *file_;
        pathname = coerce_pathname(pathname); # zu einem Pathname machen
        check_no_wildcards(pathname); # mit Wildcards -> Fehler
        pathname = use_default_dir(pathname); # Default-Directory einfügen
        if (namenullp(pathname)) { fehler_noname(pathname); } # Kein Name angegeben -> Fehler
        # Name angegeben.
        pushSTACK(pathname);
        # Directory muss existieren:
        var object namestring = assure_dir_exists(false,false); # Filename fürs Betriebssystem
        # Überprüfe, ob die Datei existiert:
        if (!file_exists(namestring)) { fehler_file_not_exists(); }
        *file_ = string_to_asciz(namestring,O(pathname_encoding)); # retten
        skipSTACK(1);
      }
      # restliche Argumente überprüfen:
      {
        var uintC count;
        dotimesC(count,argcount, {
          var object* arg_ = &NEXT(argptr);
          pushSTACK(*arg_); funcall(L(string),1); # nächstes Argument in String umwandeln
          *arg_ = string_to_asciz(value1,O(misc_encoding)); # und ASCIZ-String umwandeln
        });
      }
    }
    #ifdef EMUNIX
    # (Unter OS/2 scheint system() sicherer zu sein als spawnv(). Warum?)
    # Alle Argumente (nun ASCIZ-Strings) zusammenhängen, mit Spaces dazwischen:
    {
      var uintL argvdata_length = 0;
      {
        var object* argptr = args_pointer;
        var uintC count;
        dotimespC(count,argcount+1, {
          var object arg = NEXT(argptr); # nächstes Argument, ASCIZ-String
          argvdata_length += Sbvector_length(arg);
        });
      }
      var DYNAMIC_ARRAY(argvdata,char,argvdata_length);
      {
        var object* argptr = args_pointer;
        var char* argvdataptr = &argvdata[0];
        var uintC count;
        dotimespC(count,argcount+1, {
          var object arg = NEXT(argptr); # nächstes Argument, ASCIZ-String
          var char* ptr = TheAsciz(arg);
          var uintL len = Sbvector_length(arg);
          dotimesL(len,len-1, { *argvdataptr++ = *ptr++; } ); # und kopieren
          *argvdataptr++ = ' ';
        });
        argvdataptr[-1] = '\0';
      }
      # Programm aufrufen:
      begin_system_call();
      var int ergebnis = system(&argvdata[0]);
      end_system_call();
      # Fertig.
      set_args_end_pointer(args_pointer); # STACK aufräumen
      # Rückgabewert verwerten: =0 (OK) -> T, >0 (nicht OK) -> NIL :
      value1 = (ergebnis==0 ? T : NIL); mv_count=1;
      FREE_DYNAMIC_ARRAY(argvdata);
    }
    #endif
    #if defined(UNIX) || defined(RISCOS)
    {
      # argv-Array im Stack aufbauen und Strings in den Stack kopieren:
      var uintL argvdata_length = 0;
      {
        var object* argptr = args_pointer;
        var uintC count;
        dotimespC(count,argcount+1, {
          var object arg = NEXT(argptr); # nächstes Argument, ASCIZ-String
          argvdata_length += Sbvector_length(arg);
        });
      }
      var DYNAMIC_ARRAY(argv,char*,1+(uintL)argcount+1);
      var DYNAMIC_ARRAY(argvdata,char,argvdata_length);
      {
        var object* argptr = args_pointer;
        var char** argvptr = &argv[0];
        var char* argvdataptr = &argvdata[0];
        var uintC count;
        dotimespC(count,argcount+1, {
          var object arg = NEXT(argptr); # nächstes Argument, ASCIZ-String
          var char* ptr = TheAsciz(arg);
          var uintL len = Sbvector_length(arg);
          *argvptr++ = argvdataptr; # in argv einfüllen
          dotimespL(len,len, { *argvdataptr++ = *ptr++; } ); # und kopieren
        });
        *argvptr = NULL; # und mit Nullpointer abschließen
      }
      # einen neuen Prozess starten:
      {
        var int child;
        begin_system_call();
        begin_want_sigcld();
        if ((child = vfork()) ==0) {
          # Dieses Programmstück wird vom Child-Prozess ausgeführt:
          execv(argv[0],argv); # Programm aufrufen
          _exit(-1); # sollte dies misslingen, Child-Prozess beenden
        }
        # Dieses Programmstück wird wieder vom Aufrufer ausgeführt:
        if (child==-1) {
          # Etwas ist misslungen, entweder beim vfork oder beim execv.
          # In beiden Fällen wurde errno gesetzt.
          end_want_sigcld(); OS_error();
        }
        # Warten, bis der Child-Prozess beendet wird:
        var int status = wait2(child);
        # vgl. WAIT(2V) und #include <sys/wait.h> :
        #   WIFSTOPPED(status)  ==  ((status & 0xFF) == 0177)
        #   WEXITSTATUS(status)  == ((status & 0xFF00) >> 8)
        end_want_sigcld();
        end_system_call();
        # Fertig.
        set_args_end_pointer(args_pointer); # STACK aufräumen
        value1 = (((status & 0xFF) == 0000) # Prozess normal beendet (ohne Signal, ohne Core-Dump) ?
                  ? # ja -> Exit-Status als Wert:
                    fixnum( (status & 0xFF00) >> 8)
                  : NIL # nein -> NIL als Wert
                 );
        mv_count=1;
      }
      FREE_DYNAMIC_ARRAY(argvdata);
      FREE_DYNAMIC_ARRAY(argv);
    }
    #endif
  }

#endif

#ifdef AMIGAOS

LISPFUN(execute,1,0,norest,nokey,0,NIL)
# (EXECUTE command-string) schickt einen String an das Betriebssystem.
# Das ist in diesem Fall mit (SHELL command-string) synonym.
  {
    C_shell(); # SHELL aufrufen, selber Stackaufbau
  }

#endif

#ifdef HAVE_SHELL

# (SHELL) ruft eine Shell auf.
# (SHELL command) ruft eine Shell auf und lässt sie ein Kommando ausführen.

#if defined(AMIGAOS)
#include <dos/dostags.h>         # für SystemTags()

LISPFUN(shell,0,1,norest,nokey,0,NIL)
  {
    var object command = popSTACK();
    # As I/O is on the terminal and we obviously keep a handle on it,
    # we will also get ^C^D^E^F signals from it during command execution.
    # We choose to restore the initial signal state to avoid a double
    # interruption, even though that implies that signals sent to us
    # explicitly (Break command) in this time will be ignored.
    if (eq(command,unbound)) {
      # Kommandointerpreter aufrufen:
      run_time_stop();
      begin_system_call();
      var BOOL ergebnis = false;
      #if 0 # so einfach geht's wohl nicht
      ergebnis = Execute("",stdin_handle,stdout_handle);
      #else
      var Handle terminal = Open("*",MODE_READWRITE);
      if (!(terminal==Handle_NULL)) {
        var ULONG signals = SetSignal(0L,0L);
        ergebnis = Execute("",terminal,Handle_NULL);
        # Restore state of break signals
        SetSignal(signals,(SIGBREAKF_CTRL_C|SIGBREAKF_CTRL_D|SIGBREAKF_CTRL_E|SIGBREAKF_CTRL_F));
        Write(terminal,NLstring,1);
        Close(terminal);
      }
      #endif
      end_system_call();
      run_time_restart();
      # Rückgabewert verwerten: ausgeführt -> T, nicht gefunden -> NIL :
      value1 = (ergebnis ? T : NIL); mv_count=1;
    } else {
      # einzelnes Kommando ausführen:
      if (!stringp(command)) {
        pushSTACK(command); # Wert für Slot DATUM von TYPE-ERROR
        pushSTACK(S(string)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
        pushSTACK(command);
        pushSTACK(TheSubr(subr_self)->name);
        fehler(type_error,
               GETTEXT("~: the command should be a string, not ~")
              );
      }
      with_string_0(command,O(misc_encoding),command_asciz, {
        # Kommando ausführen:
        run_time_stop();
        begin_system_call();
        var ULONG signals = SetSignal(0L,0L);
        # Using SystemTags() instead of Execute() sends console signals to
        # the command and it gives us the command's exit code.
        var LONG ergebnis =
          SystemTags(command_asciz,
                     SYS_Input, stdin_handle,
                     # Work around bug in Emacs-18 subshell where Input() and Output()
                     # are forbiddenly the same by having Input() cloned.
                     SYS_Output, (stdin_handle == stdout_handle) ? Handle_NULL : stdout_handle,
                     SYS_UserShell, 1L,
                     TAG_DONE);
        # Restore state of break signals
        SetSignal(signals,(SIGBREAKF_CTRL_C|SIGBREAKF_CTRL_D|SIGBREAKF_CTRL_E|SIGBREAKF_CTRL_F));
        end_system_call();
        run_time_restart();
        # Rückgabewert verwerten
        value1 = L_to_I(ergebnis); mv_count=1;
      });
    }
  }

#elif defined(WIN32_NATIVE)

LISPFUNN(shell_name,0)
# (SYSTEM::SHELL-NAME) returns the name of the command shell.
  {
    value1 = O(command_shell); mv_count=1;
  }

LISPFUN(shell,0,1,norest,nokey,0,NIL)
  {
    var object command = popSTACK();
    if (eq(command,unbound))
      command = O(command_shell);
    if (!stringp(command)) {
      pushSTACK(command); # Wert für Slot DATUM von TYPE-ERROR
      pushSTACK(S(string)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
      pushSTACK(command);
      pushSTACK(TheSubr(subr_self)->name);
      fehler(type_error,
             GETTEXT("~: the command should be a string, not ~")
            );
    }
    var HANDLE prochandle;
    with_string_0(command,O(misc_encoding),command_asciz, {
      # Start new process.
      var HANDLE stdinput;
      var HANDLE stdoutput;
      var PROCESS_INFORMATION pinfo;
      begin_system_call();
      stdinput = GetStdHandle(STD_INPUT_HANDLE);
      if (stdinput == INVALID_HANDLE_VALUE) { OS_error(); }
      stdoutput = GetStdHandle(STD_OUTPUT_HANDLE);
      if (stdoutput == INVALID_HANDLE_VALUE) { OS_error(); }
      if (!MyCreateProcess(command_asciz,stdinput,stdoutput,&pinfo))
        { OS_error(); }
      if (!CloseHandle(pinfo.hThread)) { OS_error(); }
      prochandle = pinfo.hProcess;
    });
    # Wait until it terminates, get its exit status code.
    var DWORD exitcode;
    switch (WaitForSingleObject(prochandle,INFINITE)) {
      case WAIT_FAILED:
        OS_error();
      case WAIT_OBJECT_0:
        break;
      default:
        NOTREACHED
    }
    if (!GetExitCodeProcess(prochandle,&exitcode)) { OS_error(); }
    if (!CloseHandle(prochandle)) { OS_error(); }
    end_system_call();
    # Rückgabewert verwerten: =0 (OK) -> T, >0 (nicht OK) -> NIL :
    value1 = (exitcode==0 ? T : NIL); mv_count=1;
  }

#else # UNIX || MSDOS || ...

LISPFUN(shell,0,1,norest,nokey,0,NIL)
  {
    var object command = popSTACK();
    if (eq(command,unbound)) {
      # (EXECUTE shell) ausführen:
      #ifdef UNIX
      pushSTACK(O(user_shell)); # Shell-Name
      #else # MSDOS
      pushSTACK(O(command_shell)); # Shell-Name
      #endif
      funcall(L(execute),1);
    } else {
      #if defined(MSDOS) || defined(RISCOS)
      # Dem DOS-Kommandointerpreter muss man das Kommando bereits entlang
      # der Leerstellen in einzelne Teile zerlegt übergeben. Die Funktion
      # system() erledigt uns das zum Glück.
      if (!stringp(command)) {
        pushSTACK(command); # Wert für Slot DATUM von TYPE-ERROR
        pushSTACK(S(string)); # Wert für Slot EXPECTED-TYPE von TYPE-ERROR
        pushSTACK(command);
        pushSTACK(TheSubr(subr_self)->name);
        fehler(type_error,
               GETTEXT("~: the command should be a string, not ~")
              );
      }
      with_string_0(command,O(misc_encoding),command_asciz, {
        begin_system_call();
        # Programm aufrufen:
        var int ergebnis = system(command_asciz);
        end_system_call();
        # Rückgabewert verwerten: =0 (OK) -> T, >0 (nicht OK) -> NIL :
        value1 = (ergebnis==0 ? T : NIL); mv_count=1;
      });
      #else
      # (EXECUTE shell "-c" command) ausführen:
      pushSTACK(O(command_shell)); # Shell-Name
      pushSTACK(O(command_shell_option)); # Shell-Option "-c"
      #ifdef EMUNIX
      # Unter DOS 2.x, 3.x kann das Optionen-Zeichen ein anderes sein!
      if ((_osmode == DOS_MODE) && (_osmajor < 4)) {
        var uintB swchar = _swchar();
        if (swchar) # evtl. "/C" durch etwas anderes ersetzen
          TheSstring(STACK_0)->data[0] = ascii(swchar); # (destruktiv)
      }
      #endif
      pushSTACK(command);
      funcall(L(execute),3);
      #endif
    }
  }

#endif

#endif

LISPFUNN(savemem,1)
# (SAVEMEM pathname) speichert ein Speicherabbild unter pathname ab.
  {
    # (OPEN pathname :direction :output) ausführen:
    # pathname als 1. Argument
    pushSTACK(S(Kdirection)); # :DIRECTION als 2. Argument
    pushSTACK(S(Koutput)); # :OUTPUT als 3. Argument
    #ifdef UNIX
    # Unter Unix mit mmap() darf man existierende .mem-Files nicht einfach
    # überschreiben, weil laufende Lisp-Prozesse dadurch abstürzen würden.
    # Deswegen :if-exists :rename-and-delete.
    #if defined(UNIX_LINUX) && defined(SINGLEMAP_MEMORY)
    # Under Linux 1.3.20, when the mem file to be saved is on an NFS volume
    # and has the same filename as the mem file we started with, the GC
    # done by savemem (once the new mem file has been created and still has
    # size 0) will crash. Looks like a bug in the Linux NFS client, which
    # causes random pages to be mapped in instead of pages from the renamed
    # old mem file. Workaround: Do a full GC, forcing all the old mem file's
    # contents into memory immediately.
    gar_col();
    #endif
    pushSTACK(S(Kif_exists)); # :IF-EXISTS als 4. Argument
    pushSTACK(S(Krename_and_delete)); # :RENAME-AND-DELETE als 5. Argument
    funcall(L(open),5);
    #else
    #ifdef SELFMADE_MMAP
    # Bei selfmade_mmap muss man das existierende .mem-File erst komplett in
    # den Speicher laden. Andere laufende Lisp-Prozesse werden aber abstürzen.
    gar_col();
    #endif
    funcall(L(open),3);
    #endif
    # Speicherabbild in die Datei schreiben:
    # (Den Stream muss die Funktion savemem() schließen, auch im Fehlerfalle.)
    savemem(value1);
    value1 = T; mv_count=1; # 1 Wert T
  }

#ifdef DYNAMIC_MODULES

LISPFUNN(dynload_modules,2)
# (SYSTEM::DYNLOAD-MODULES pathname stringlist)
# loads a shared library, containing a number of modules.
  {
    # Pathname in String umwandeln:
    pushSTACK(subr_self); # subr_self retten
    pushSTACK(STACK_2); pushSTACK(T); funcall(L(namestring),2); # (NAMESTRING pathname T)
    STACK_2 = value1; subr_self = popSTACK();
    # Strings überprüfen und in den Stack legen:
    var uintL stringcount = llength(STACK_0);
    var object* arg_ = &STACK_0;
    {
      var uintL count;
      dotimesL(count,stringcount, {
        if (!stringp(Car(*arg_))) fehler_string(Car(*arg_));
        pushSTACK(string_to_asciz(Car(*arg_),Symbol_value(S(ascii))));
        *arg_ = Cdr(*arg_);
      });
      # test for nullp(*arg_) ??
    }
    {
      var const char * libpath = TheAsciz(string_to_asciz(*(arg_ STACKop 1),O(pathname_encoding)));
      var DYNAMIC_ARRAY(modnames,const char *,stringcount);
      if (stringcount > 0) {
        var uintL count;
        var object* ptr1 = STACK STACKop stringcount;
        var const char * * ptr2 = modnames;
        dotimespL(count,stringcount, { *ptr2++ = TheAsciz(NEXT(ptr1)); });
      }
      dynload_modules(libpath,stringcount,modnames);
      FREE_DYNAMIC_ARRAY(modnames);
    }
    skipSTACK(stringcount+1);
    value1 = popSTACK(); mv_count=1; # Library-Name als Wert
  }

#endif

# =============================================================================

#ifdef HAVE_DISASSEMBLER

# Finding the full path of the executable.
# Bruno Haible 20.12.1994

# This assumes that the executable is not removed or renamed while running.

# file name of the executable
local char* executable_name = NULL;
#define default_executable_name  "lisp.run"

# file descriptor of the executable
# (Only used to verify that we find the correct executable.)
local int executable_fd = -1;

# maybe_executable(pathname)
# checks whether a given pathname may belong to the executable.
local bool maybe_executable (const char * filename);
local bool maybe_executable(filename)
  var const char * filename;
  {
    var struct stat statexe;
    var struct stat statfile;
    if (access(filename,R_OK|X_OK) < 0)
      return false;
    if (executable_fd < 0)
      return true;
    # If we already have an executable_fd, check that filename points to
    # the same inode.
    if (fstat(executable_fd,&statexe) < 0)
      return true;
    if (stat(filename,&statfile) < 0)
      return false;
    if (statfile.st_dev
        && statfile.st_dev == statexe.st_dev
        && statfile.st_ino == statexe.st_ino
       )
      return true;
    return false;
  }

# find_executable(program_name)
# is to be called immediately after the program starts,
# with program_name = argv[0],
# before any chdir() operation and before any setenv("PATH",...).
# It determines the full program path and opens a file descriptor to
# the executable, for later use.
# Return value is 0 if successful, -1 and errno set if not.
global int find_executable (const char * program_name);
global int find_executable(program_name)
  var const char * program_name;
  {
    # Don't need to execute this more than once.
    if (!(executable_name == NULL)) return 0;
    #ifdef UNIX_LINUX
    # The executable is accessible as /proc/<pid>/exe. We try this first
    # because it is safer: no race condition w.r.t. the file system. It may
    # fail, however, if the user has not compiled /proc support into his
    # kernel.
    {
      var char buf[6+10+5];
      var int fd;
      sprintf(buf,"/proc/%d/exe",getpid());
      fd = OPEN(buf,O_RDONLY,my_open_mask);
      if (fd >= 0)
        executable_fd = fd;
    }
    #endif
    # Now we guess the executable's full path. We assume the executable
    # has been called via execlp() or execvp() with properly set up argv[0].
    # The login(1) convention to add a '-' prefix to argv[0] is not supported.
    var bool has_slash = false;
    {
      var const char * p;
      for (p = program_name; *p; p++)
        if (*p == '/') {
          has_slash = true; break;
      }
    }
    if (!has_slash) {
      # exec searches paths without slashes in the directory list given
      # by $PATH.
      var const char * path = getenv("PATH");
      if (!(path==NULL)) {
        var const char * p;
        var const char * p_next;
        for (p = path; *p; p = p_next) {
          var const char * q;
          var uintL p_len;
          for (q = p; *q; q++) { if (*q == ':') break; }
          p_len = q-p; p_next = (*q=='\0' ? q : q+1);
          # We have a path item at p, of length p_len.
          # Now concatenate the path item and program_name.
          var char * concat_name = (char*) malloc(p_len + strlen(program_name) + 2);
          if (concat_name == NULL) { errno = ENOMEM; goto notfound; }
          if (p_len == 0) {
            # empty PATH element designates the current directory
            strcpy(concat_name,program_name);
          } else {
            memcpy(concat_name, p, p_len);
            concat_name[p_len] = '/';
            strcpy(concat_name+p_len+1, program_name);
          }
          if (maybe_executable(concat_name)) {
            # Assume we have found the executable
            program_name = concat_name; goto resolve;
          }
          free(concat_name);
        }
      }
      # Not found in the PATH, assume the current directory.
    }
    # exec treats paths containing slashes as relative to the current directory.
    if (maybe_executable(program_name)) {
     resolve:
      # resolve program_name:
      executable_name = (char*) malloc(MAXPATHLEN);
      if (executable_name == NULL) { errno = ENOMEM; goto notfound; }
      if (realpath(program_name,executable_name) == NULL) {
        free(executable_name); goto notfound;
      }
      return 0;
    }
    errno = ENOENT;
   notfound:
    executable_name = default_executable_name; return -1;
  }

# (SYS::PROGRAM-NAME) returns the executable's name.
LISPFUNN(program_name,0)
  {
    value1 = asciz_to_string(executable_name,O(pathname_encoding)); mv_count=1;
  }

#endif

global char* argv_lisplibdir = NULL; # set during main()
# (SYS::LIB-DIRECTORY) returns clisp's private library directory (called
# $(lisplibdir) in the Makefile).
LISPFUNN(lib_directory,0)
  {
    if (!(argv_lisplibdir==NULL)) {
      value1 = asciz_dir_to_pathname(argv_lisplibdir,O(misc_encoding));
    } else {
      pushSTACK(TheSubr(subr_self)->name);
      fehler(error,
             GETTEXT("~: library directory is not known, use a command line option to specify it")
            );
    }
    mv_count=1;
  }

# =============================================================================

#ifdef EXPORT_SYSCALLS

# This piece of code is under the responsibility of Sam Steingold.

#ifdef UNIX

#define PASSWD_TO_STACK(pwd)                                   \
  pushSTACK(asciz_to_string(pwd->pw_name,O(misc_encoding)));   \
  pushSTACK(asciz_to_string(pwd->pw_passwd,O(misc_encoding))); \
  pushSTACK(UL_to_I(pwd->pw_uid));                             \
  pushSTACK(UL_to_I(pwd->pw_gid));                             \
  pushSTACK(asciz_to_string(pwd->pw_gecos,O(misc_encoding)));  \
  pushSTACK(asciz_to_string(pwd->pw_dir,O(misc_encoding)));    \
  pushSTACK(asciz_to_string(pwd->pw_shell,O(misc_encoding)))

# return the data for the user as 7 values (slots of struct passwd)
# or a list of simple vectors of length 7 if user is NIL
LISPFUN(user_data_,1,0,norest,nokey,0,NIL)
# (POSIX::USER-DATA-INTERNAL user)
# if you modify this function wrt its return values,
# you should modify POSIX:USER-DATA in posix.lisp accordingly
  {
    var object user = popSTACK();
    struct passwd *pwd = NULL;

    if (nullp(user)) { # all users as a list
      int count = 0;
      begin_system_call();
      for (; (pwd = getpwent()); count++) {
        PASSWD_TO_STACK(pwd);
        funcall(L(vector),7);
        pushSTACK(value1);
      }
      endpwent();
      end_system_call();
      value1 = listof(count); mv_count = 1;
      return;
    }

    begin_system_call();
    if (posfixnump(user))
      pwd = getpwuid(posfixnum_to_L(user));
    elif (eq(user,S(Kdefault)))
      pwd = unix_user_pwd();
    elif (symbolp(user))
      pwd = getpwnam(TheAsciz(string_to_asciz(Symbol_name(user),
                                              O(misc_encoding))));
    elif (stringp(user))
      pwd = getpwnam(TheAsciz(string_to_asciz(user,O(misc_encoding))));
    else {
      end_system_call(); fehler_string_integer(user);
    }
    end_system_call();

    if (NULL == pwd) { OS_error(); }
    PASSWD_TO_STACK(pwd);
    funcall(L(values),7);
  }

# Lisp interface to stat(2), lstat(2) and fstat(2)
# the first arg can be: file stream, pathname, string, symbol, number.
# the return values are: the file descriptor (int) or the file name
# (string) on which the appropriate stat function was called,
# as well as the 13 slots of the struct stat.
LISPFUN(file_stat_,1,1,norest,nokey,0,NIL)
# (POSIX::FILE-STAT-INTERNAL file &optional link-p)
# if you modify this function wrt its return values,
# you should modify POSIX:FILE-STAT in posix.lisp accordingly
  {
    var object link = popSTACK();
    var object file = popSTACK();
    struct stat buf;

    if (builtin_stream_p(file)) {
      pushSTACK(file);
      funcall(L(built_in_stream_open_p),1);
      if (nullp(value1)) {        # closed stream
        file = as_file_stream(file);
        if (nullp(TheStream(file)->strm_file_truename))
          fehler_file_stream_unnamed(file);
        file = TheStream(file)->strm_file_truename;
      } else                      # open stream
        file = stream_fd(file);
    } elif (symbolp(file))
      file = Symbol_name(file);

    if (pathnamep(file)) {
      pushSTACK(file);
      funcall(L(namestring),1);
      file = value1;
    }

    if (posfixnump(file)) {
      begin_system_call();
      if (fstat(posfixnum_to_L(file),&buf) < 0) { OS_error(); }
      end_system_call();
    } else if (stringp(file)) {
      var const char * string = TheAsciz(string_to_asciz(file,O(pathname_encoding)));
      begin_system_call();
      if (((eq(link,unbound) || nullp(link))
           ? stat(string,&buf) : lstat(string,&buf)
          ) < 0)
        OS_error();
      end_system_call();
    } else
      fehler_pathname_designator(file);

    pushSTACK(file);                    # the object stat'ed
    pushSTACK(L_to_I(buf.st_dev));      # device
    pushSTACK(UL_to_I(buf.st_ino));     # inode
    pushSTACK(UL_to_I(buf.st_mode));    # protection
    pushSTACK(UL_to_I(buf.st_nlink));   # number of hard links
    pushSTACK(UL_to_I(buf.st_uid));     # user ID of owner
    pushSTACK(UL_to_I(buf.st_gid));     # group ID of owner
    pushSTACK(L_to_I(buf.st_rdev));     # device type (if inode device)
    pushSTACK(L_to_I(buf.st_size));     # total size, in bytes
    pushSTACK(UL_to_I(buf.st_blksize)); # blocksize for filesystem I/O
    pushSTACK(UL_to_I(buf.st_blocks));  # number of blocks allocated
    pushSTACK(UL_to_I(buf.st_atime+UNIX_LISP_TIME_DIFF)); # time of last access
    pushSTACK(UL_to_I(buf.st_mtime+UNIX_LISP_TIME_DIFF)); # last modification
    pushSTACK(UL_to_I(buf.st_ctime+UNIX_LISP_TIME_DIFF)); # time of last change
    funcall(L(values),14);
  }

#endif # UNIX
#endif # EXPORT_SYSCALLS

# =============================================================================

#ifdef EMUNIX

# Umgehen eines lästigen ENAMETOOLONG Errors bei Benutzung von langen
# Filenamen auf FAT-Drives unter OS/2:

#undef chdir
#undef access
#undef stat
#undef unlink
#undef rename
#undef __findfirst
#undef mkdir
#undef open
#undef creat
#undef spawnv

# path2 := verkürzte Kopie von path1
local void shorten_path (const char* path1, char* path2)
  {
    var const uintB* p1 = path1;
    var uintB* p2 = path2;
    var uintB c;
    var uintC wordlength = 0; # bisherige Länge in Name oder Typ
    var uintC maxwordlength = 8; # = 8 im Namen, = 3 im Typ
    loop {
      c = *p1++;
      if (c=='\0') {
        *p2++ = c; break;
      }
      if ((c=='\\') || (c=='/') || (c==':')) {
        *p2++ = c; wordlength = 0; maxwordlength = 8;
      } elif (c=='.') {
        *p2++ = c; wordlength = 0; maxwordlength = 3;
      } else {
        if (++wordlength <= maxwordlength)
          *p2++ = c;
      }
    }
  }

global int my_chdir(path)
  var CONST char* path;
  {
    var int erg = chdir(path);
    if ((erg<0) && (errno==ENAMETOOLONG)) {
      var char* shorter_path = alloca(asciz_length(path)+1);
      shorten_path(path,shorter_path);
      erg = chdir(shorter_path);
    }
    return erg;
  }

global int my_access(path,amode)
  var CONST char* path;
  var int amode;
  {
    var int erg = access(path,amode);
    if ((erg<0) && (errno==ENAMETOOLONG)) {
      var char* shorter_path = alloca(asciz_length(path)+1);
      shorten_path(path,shorter_path);
      erg = access(shorter_path,amode);
    }
    return erg;
  }

global int my_stat(path,buf)
  var CONST char* path;
  var struct stat * buf;
  {
    var int erg = stat(path,buf);
    if ((erg<0) && (errno==ENAMETOOLONG)) {
      var char* shorter_path = alloca(asciz_length(path)+1);
      shorten_path(path,shorter_path);
      erg = stat(shorter_path,buf);
    }
    return erg;
  }

global int my_unlink(path)
  var CONST char* path;
  {
    var int erg = unlink(path);
    if ((erg<0) && (errno==ENAMETOOLONG)) {
      var char* shorter_path = alloca(asciz_length(path)+1);
      shorten_path(path,shorter_path);
      erg = unlink(shorter_path);
    }
    return erg;
  }

global int my_rename(oldpath,newpath)
  var CONST char* oldpath;
  var CONST char* newpath;
  {
    var int erg = rename(oldpath,newpath);
    if ((erg<0) && (errno==ENAMETOOLONG)) {
      var char* shorter_oldpath = alloca(asciz_length(oldpath)+1);
      shorten_path(oldpath,shorter_oldpath);
      erg = rename(shorter_oldpath,newpath);
      if ((erg<0) && (errno==ENAMETOOLONG)) {
        var char* shorter_newpath = alloca(asciz_length(newpath)+1);
        shorten_path(newpath,shorter_newpath);
        erg = rename(shorter_oldpath,shorter_newpath);
      }
    }
    return erg;
  }

global int my___findfirst(path,attrib,ffblk)
  var const char* path;
  var int attrib;
  var struct ffblk * ffblk;
  {
    var int erg = __findfirst(path,attrib,ffblk);
    if ((erg<0) && (errno==ENAMETOOLONG)) {
      var char* shorter_path = alloca(asciz_length(path)+1);
      shorten_path(path,shorter_path);
      erg = __findfirst(shorter_path,attrib,ffblk);
    }
    return erg;
  }

global int my_mkdir(path,attrib)
  var CONST char* path;
  var long attrib;
  {
    var int erg = mkdir(path,attrib);
    if ((erg<0) && (errno==ENAMETOOLONG)) {
      var char* shorter_path = alloca(asciz_length(path)+1);
      shorten_path(path,shorter_path);
      erg = mkdir(shorter_path,attrib);
    }
    return erg;
  }

global int my_open(path,flags)
  var CONST char* path;
  var int flags;
  {
    var int erg = open(path,flags);
    if ((erg<0) && (errno==ENAMETOOLONG)) {
      var char* shorter_path = alloca(asciz_length(path)+1);
      shorten_path(path,shorter_path);
      erg = open(shorter_path,flags);
    }
    return erg;
  }

#define creat(path,mode)  open(path,O_RDWR|O_TRUNC|O_CREAT,mode)
global int my_creat(path,pmode)
  var CONST char* path;
  var int pmode;
  {
    var int erg = creat(path,pmode);
    if ((erg<0) && (errno==ENAMETOOLONG)) {
      var char* shorter_path = alloca(asciz_length(path)+1);
      shorten_path(path,shorter_path);
      erg = creat(shorter_path,pmode);
    }
    return erg;
  }

global int my_spawnv(pmode,path,argv)
  var int pmode;
  var CONST char* path;
  var CONST char* CONST * argv;
  {
    var int erg = spawnv(pmode,path,argv);
    if ((erg<0) && (errno==ENAMETOOLONG)) {
      var char* shorter_path = alloca(asciz_length(path)+1);
      shorten_path(path,shorter_path);
      erg = spawnv(pmode,shorter_path,argv);
    }
    return erg;
  }

#endif

# ============================================================================

#ifdef DEBUG_TRANSLATE_PATHNAME
#undef DEBUG_TRANSLATE_PATHNAME
#undef DOUT
#endif
