OpenScanner as in PO2013

src/Files.Mod

@@ -1,816 +1,816 @@
-MODULE Files;
-(** Standard data type input-output
-
-    Little Endian,
-    SInt: 2 bytes, Int: 4 bytes, LInt: 8 bytes
-    ORD({0}) = 1,
-    FALSE = 0, TRUE = 1
-    IEEE Real Format,
-    Null-terminated strings,
-    compact numbers according to M. Odersky *)
-
-IMPORT SYSTEM, Platform, Heap, Strings, Out, Utf8;
-
-CONST
-  PathDelimiter = Platform.PathDelimiter;
-  PathSeparator = Platform.PathSeparator;
-
-  NumBufs = 4;
-  BufSize = 4096;
-
-  (* No file states, used when FileDesc.fd = Platform.InvalidHandleValue() *)
-  open   = 0; (* OS File has been opened *)
-  create = 1; (* OS file needs to be created *)
-  close  = 2; (* Flag used by Files.Register to tell Create to create the file
-                 using it's registerName directly, rather than to create a
-                 temporary file: i.e. since we're closing and all data is still
-                 in buffers bypass writing to temp file and then renaming and
-                 just write directly to final register name *)
-
-TYPE
-  SBYTE* = BYTE;
-  BYTE* = UBYTE;
-
-  FileName = ARRAY 256 OF CHAR;
-  File* = POINTER TO FileDesc;
-  Buffer = POINTER TO BufDesc;
-
-  FileDesc = RECORD
-    workName, registerName: FileName;
-    tempFile: BOOLEAN;
-    identity: Platform.FileIdentity;
-    fd-: Platform.FileHandle;
-    len, pos: LONGINT;
-    bufs: ARRAY NumBufs OF Buffer;
-    swapper, state: SHORTINT;
-    next: POINTER [notag] TO FileDesc
-  END;
-
-  BufDesc = RECORD
-    f: File;
-    chg: BOOLEAN;
-    org: LONGINT;
-    size: INTEGER;
-    data: ARRAY BufSize OF SBYTE
-  END;
-
-  Rider* = RECORD
-    res*: INTEGER; (* Residue (byte count not read) at eof of ReadBytes *)
-    eof*: BOOLEAN;
-    buf: Buffer;
-    org: LONGINT; (* File offset of block containing current position *)
-    offset: INTEGER (* Current position offset within block at org. *)
-  END;
-
-VAR
-  (* Array of files backed by an OS file: open, registered or temporary. *)
-  files: POINTER [notag] TO FileDesc;
-
-  tempno: INTEGER;
-  home: ARRAY 1024 OF CHAR;
-  SearchPath: ARRAY 4096 OF CHAR;
-
-PROCEDURE -IdxTrap(pos: INTEGER) '__HALT(-1, "Files.Mod", pos)';
-
-PROCEDURE^ Finalize(o: SYSTEM.PTR);
-
-PROCEDURE Err(IN s: ARRAY OF CHAR; f: File; errcode: Platform.ErrorCode);
-BEGIN
-  Out.Ln; Out.String('-- '); Out.String(s); Out.String(': ');
-  IF f # NIL THEN
-    IF f.registerName # '' THEN Out.String(f.registerName)
-    ELSE Out.String(f.workName)
-    END;
-    IF f.fd # 0 THEN Out.String(' f.fd = '); Out.Int(f.fd, 1) END
-  END;
-  IF errcode # 0 THEN Out.String(' errcode = '); Out.Int(errcode, 1) END;
-  Out.Ln;
-  HALT(99)
-END Err;
-
-PROCEDURE MakeFileName(IN dir, name: ARRAY OF CHAR; VAR dest: ARRAY OF CHAR);
-VAR i, j: INTEGER;
-BEGIN i := 0; j := 0;
-  WHILE dir[i] # 0X DO dest[i] := dir[i]; INC(i) END;
-  IF dest[i-1] # PathDelimiter THEN dest[i] := PathDelimiter; INC(i) END;
-  WHILE name[j] # 0X DO dest[i] := name[j]; INC(i); INC(j) END;
-  dest[i] := 0X
-END MakeFileName;
-
-PROCEDURE GetTempName(IN finalName: ARRAY OF CHAR; VAR name: ARRAY OF CHAR);
-VAR n, i: INTEGER;
-  q: ARRAY 256 OF SHORTCHAR;
-BEGIN INC(tempno); Platform.GetTempPath(q); Utf8.Decode(q, name);
-  i := 0; WHILE name[i] # 0X DO INC(i) END;
-
-  name[i] := 'o'; INC(i); name[i] := 'b'; INC(i); name[i] := 'e'; INC(i);
-  name[i] := 'r'; INC(i); name[i] := 'o'; INC(i); name[i] := 'n'; INC(i);
-  name[i] := '.'; INC(i); n := tempno;
-  REPEAT name[i] := CHR(n MOD 10 + 30H); n := n DIV 10; INC(i) UNTIL n = 0;
-
-  name[i] := '.'; INC(i); n := Platform.PID;
-  REPEAT name[i] := CHR(n MOD 10 + 30H); n := n DIV 10; INC(i) UNTIL n = 0;
-  name[i] := 0X
-END GetTempName;
-
-(* When registering a file, it may turn out that the name we want to use
-   is aready in use by another File. E.g. the compiler opens and reads
-   an existing symbol file if present before creating an updated one.
-   When this happens on Windows, creation of the new file will be blocked
-   by the presence of the old one because it is in a open state. Further,
-   on both Unix and Windows systems we want behaviour to match that of
-   a real Oberon system, where registering the new file has the effect of
-   unregistering the old file. To simulate this we need to change the old
-   Files.File back to a temp file. *)
-PROCEDURE Deregister(IN name: ARRAY OF CHAR);
-VAR identity: Platform.FileIdentity;
-  osfile: File;
-  error: Platform.ErrorCode;
-  q, s: ARRAY 2048 OF SHORTCHAR;
-BEGIN
-  Utf8.Encode(name, q);
-  IF Platform.IdentifyByName(q, identity) = 0 THEN
-    (* The name we are registering is an already existing file. *)
-    osfile := files;
-    WHILE (osfile # NIL) & ~Platform.SameFile(osfile.identity, identity) DO
-      osfile := osfile.next
-    END;
-    IF osfile # NIL THEN
-      (* osfile is the FileDesc corresponding to the file name we are hoping
-         to register. Turn it into a temporary file. *)
-      ASSERT(~osfile.tempFile); ASSERT(osfile.fd >= 0);
-      osfile.registerName := osfile.workName;
-      GetTempName(osfile.registerName, osfile.workName);
-      osfile.tempFile := TRUE;
-      error := Platform.CloseFile(osfile.fd);
-      osfile.state := close;
-      Utf8.Encode(osfile.registerName, q);
-      Utf8.Encode(osfile.workName, s);
-      error := Platform.RenameFile(q, s);
-      IF error # 0 THEN
-        Err('Could not rename previous version of file being registered',
-          osfile, error)
-      END
-    END
-  END
-END Deregister;
-
-(** Makes sure there is an OS file backing this Oberon file.
-    Used when more data has been written to an unregistered new file than
-    buffers can hold, or when registering a new file whose data is all in
-    buffers. *)
-PROCEDURE Create(f: File);
-VAR done: BOOLEAN;
-  error: Platform.ErrorCode;
-  err: ARRAY 32 OF CHAR;
-  q: ARRAY 2048 OF SHORTCHAR;
-BEGIN
-  IF f.fd = Platform.InvalidHandleValue() THEN
-    IF f.state = create THEN
-      (* New file with enough data written to exceed buffers, so we need to
-         create a temporary file to back it. *) 
-      GetTempName(f.registerName, f.workName); f.tempFile := TRUE
-    ELSE
-      ASSERT(f.state = close);
-      (* New file with all data in buffers being registered. No need for a
-         temp file, will just write the buffers to the registerName. *)
-      Deregister(f.registerName);
-      f.workName := f.registerName; f.registerName := ''; f.tempFile := FALSE
-    END;
-    (* Unlink first to avoid stale NFS handles and to avoid reuse of inodes *)
-    Utf8.Encode(f.workName, q);
-    error := Platform.DeleteFile(q);
-
-    error := Platform.NewFile(q, f.fd);
-    done := error = 0;
-    IF done THEN
-      (* Link this file into the list of OS backed files. *)
-      f.next := files; files := f;
-      INC(Heap.FileCount);
-      Heap.RegisterFinalizer(f, Finalize);
-      f.state := open;
-      f.pos   := 0;
-      error   := Platform.Identify(f.fd, f.identity);
-    ELSE
-      IF Platform.NoSuchDirectory(error) THEN err := 'no such directory'
-      ELSIF Platform.TooManyFiles(error) THEN err := 'too many files open'
-      ELSE err := 'file not created'
-      END;
-      Err(err, f, error)
-    END
-  END
-END Create;
-
-PROCEDURE Flush(buf: Buffer);
-VAR error: Platform.ErrorCode;
-  f: File;
-BEGIN
-  IF buf.chg THEN f := buf.f; Create(f);
-    IF buf.org # f.pos THEN
-      error := Platform.Seek(f.fd, buf.org, Platform.SeekSet)
-    END;
-    error := Platform.Write(f.fd, SYSTEM.ADR(buf.data), buf.size);
-    IF error # 0 THEN Err('error writing file', f, error) END;
-    f.pos := buf.org + buf.size; buf.chg := FALSE;
-    (* Update identity with new modification time. *)
-    error := Platform.Identify(f.fd, f.identity);
-    IF error # 0 THEN Err('error identifying file', f, error) END
-  END
-END Flush;
-
-PROCEDURE CloseOSFile(f: File);
-(* Close the OS file handle and remove f from 'files' *)
-VAR prev: File; error: Platform.ErrorCode;
-BEGIN
-  IF files = f THEN files := f.next
-  ELSE
-    prev := files;
-    WHILE (prev # NIL) & (prev.next # f) DO prev := prev.next END;
-    IF prev.next # NIL THEN prev.next := f.next END
-  END;
-  error := Platform.CloseFile(f.fd);
-  f.fd := Platform.InvalidHandleValue(); f.state := create; DEC(Heap.FileCount)
-END CloseOSFile;
-
-PROCEDURE Close*(f: File);
-VAR i: INTEGER;
-BEGIN
-  IF (f.state # create) OR (f.registerName # '') THEN
-    Create(f); i := 0;
-    WHILE (i < NumBufs) & (f.bufs[i] # NIL) DO Flush(f.bufs[i]); INC(i) END
-  END
-END Close;
-
-PROCEDURE Length*(f: File): LONGINT;
-BEGIN RETURN f.len END Length;
-
-PROCEDURE New*(IN name: ARRAY OF CHAR): File;
-VAR f: File;
-BEGIN
-  NEW(f); f.workName := ''; f.registerName := name$;
-  f.fd := Platform.InvalidHandleValue(); f.state := create;
-  f.len := 0; f.pos := 0; f.swapper := -1 ;
-RETURN f END New;
-
-PROCEDURE ScanPath(VAR pos: INTEGER; VAR dir: ARRAY OF CHAR);
-(* Extract next individual directory from searchpath starting at pos,
-   updating pos and returning dir.
-   Supports ~, ~user and blanks inside path *)
-VAR i: INTEGER; ch: CHAR;
-BEGIN
-  i := 0;
-  IF SearchPath = '' THEN (* Default search path is the current directory *)
-    IF pos = 0 THEN dir[0] := '.'; i := 1; INC(pos) END
-  ELSE
-    ch := SearchPath[pos];
-    WHILE (ch = ' ') OR (ch = PathSeparator) DO
-      INC(pos); ch := SearchPath[pos]
-    END;
-    IF ch = '~' THEN
-      INC(pos); ch := SearchPath[pos];
-      WHILE home[i] # 0X DO dir[i] := home[i]; INC(i) END;
-      IF (ch # PathDelimiter) & (ch # 0X) & (ch # PathSeparator) & (ch # ' ')
-      THEN WHILE (i > 0) & (dir[i - 1] # PathDelimiter) DO DEC(i) END
-      END
-    END;
-    WHILE (ch # 0X) & (ch # PathSeparator) DO
-      dir[i] := ch; INC(i); INC(pos); ch := SearchPath[pos]
-    END;
-    WHILE (i > 0) & (dir[i - 1] = ' ') DO DEC(i) END
-  END;
-  dir[i] := 0X
-END ScanPath;
-
-PROCEDURE HasDir(IN name: ARRAY OF CHAR): BOOLEAN;
-VAR i: INTEGER; ch: CHAR;
-BEGIN i := 0; ch := name[0];
-  WHILE (ch # 0X) & (ch # PathDelimiter) DO INC(i); ch := name[i] END ;
-RETURN ch = PathDelimiter END HasDir;
-
-PROCEDURE CacheEntry(identity: Platform.FileIdentity): File;
-VAR f: File; i: INTEGER; error: Platform.ErrorCode;
-BEGIN f := files;
-  WHILE f # NIL DO
-    IF Platform.SameFile(identity, f.identity) THEN
-      IF ~Platform.SameFileTime(identity, f.identity) THEN i := 0;
-        WHILE i < NumBufs DO
-          IF f.bufs[i] # NIL THEN f.bufs[i].org := -1; f.bufs[i] := NIL END;
-          INC(i)
-        END;
-        f.swapper := -1; f.identity := identity;
-        error := Platform.FileSize(f.fd, f.len)
-      END;
-      RETURN f
-    END;
-    f := f.next
-  END;
-  RETURN NIL
-END CacheEntry;
-
-PROCEDURE Old*(IN name: ARRAY OF CHAR): File;
-VAR f: File;
-  fd: Platform.FileHandle;
-  pos: INTEGER;
-  done: BOOLEAN;
-  dir, path: ARRAY 256 OF CHAR;
-  error: Platform.ErrorCode;
-  identity: Platform.FileIdentity;
-  q: ARRAY 4096 OF SHORTCHAR;
-BEGIN
-  IF name # '' THEN
-    IF HasDir(name) THEN dir := ''; path := name$
-    ELSE pos := 0; ScanPath(pos, dir);
-      MakeFileName(dir, name, path); ScanPath(pos, dir)
-    END;
-    LOOP Utf8.Encode(path, q);
-      error := Platform.OldRW(q, fd); done := error = 0;
-      IF ~done & Platform.TooManyFiles(error) THEN
-        Err('too many files open', f, error)
-      END;
-      IF ~done & Platform.Inaccessible(error) THEN
-        error := Platform.OldRO(q, fd); done := error = 0
-      END;
-      IF ~done & ~Platform.Absent(error) THEN
-        Out.String('Warning: Files.Old '); Out.String(name);
-        Out.String(' error = '); Out.Int(error, 0); Out.Ln
-      END;
-      IF done THEN
-        error := Platform.Identify(fd, identity);
-        f := CacheEntry(identity);
-        IF f # NIL THEN
-          error := Platform.CloseFile(fd); (* fd not needed, f.fd is used *)
-          RETURN f
-        ELSE NEW(f); Heap.RegisterFinalizer(f, Finalize);
-          f.fd := fd; f.state := open; f.pos := 0; f.swapper := -1;
-          error := Platform.FileSize(fd, f.len);
-          f.workName := name$; f.registerName := ''; f.tempFile := FALSE;
-          f.identity := identity;
-          f.next := files; files := f; INC(Heap.FileCount);
-          RETURN f
-        END
-      ELSIF dir = '' THEN RETURN NIL
-      ELSE MakeFileName(dir, name, path); ScanPath(pos, dir)
-      END
-    END
-  ELSE RETURN NIL
-  END
-END Old;
-
-PROCEDURE Purge*(f: File);
-VAR i: INTEGER;
-  identity: Platform.FileIdentity;
-  error: Platform.ErrorCode;
-BEGIN i := 0;
-  WHILE i < NumBufs DO
-    IF f.bufs[i] # NIL THEN f.bufs[i].org := -1; f.bufs[i] := NIL END;
-    INC(i)
-  END;
-  IF f.fd # Platform.InvalidHandleValue() THEN
-    error := Platform.TruncateFile(f.fd, 0);
-    error := Platform.Seek(f.fd, 0, Platform.SeekSet)
-  END;
-  f.pos := 0; f.len := 0; f.swapper := -1;
-  error := Platform.Identify(f.fd, identity);
-  Platform.SetMTime(f.identity, identity)
-END Purge;
-
-PROCEDURE GetDate*(f: File; VAR t, d: INTEGER);
-VAR identity: Platform.FileIdentity;
-  error: Platform.ErrorCode;
-BEGIN Create(f); error := Platform.Identify(f.fd, identity);
-  Platform.MTimeAsClock(identity, t, d)
-END GetDate;
-
-PROCEDURE Pos*(VAR r: Rider): LONGINT;
-BEGIN RETURN r.org + r.offset
-END Pos;
-
-PROCEDURE Set*(VAR r: Rider; f: File; pos: LONGINT);
-VAR org: LONGINT;
-  offset, i, n: INTEGER;
-  buf: Buffer;
-  error: Platform.ErrorCode;
-BEGIN
-  IF f # NIL THEN
-    IF pos > f.len THEN pos := f.len ELSIF pos < 0 THEN pos := 0 END;
-    offset := SHORT(pos MOD BufSize); org := pos - offset; i := 0;
-    WHILE (i < NumBufs) & (f.bufs[i] # NIL) & (org # f.bufs[i].org) DO
-      INC(i)
-    END;
-    IF i < NumBufs THEN
-      IF f.bufs[i] = NIL THEN
-        NEW(buf); buf.chg := FALSE; buf.org := -1; buf.f := f; f.bufs[i] := buf
-      ELSE buf := f.bufs[i]
-      END
-    ELSE f.swapper := SHORT((f.swapper + 1) MOD NumBufs);
-      buf := f.bufs[f.swapper];
-      Flush(buf)
-    END;
-    IF buf.org # org THEN
-      IF org = f.len THEN buf.size := 0
-      ELSE Create(f);
-        IF f.pos # org THEN
-          error := Platform.Seek(f.fd, org, Platform.SeekSet)
-        END;
-        error := Platform.ReadBuf(f.fd, buf.data, n);
-        IF error # 0 THEN Err('read from file not done', f, error) END;
-        f.pos := org + n;
-        buf.size := n
-      END;
-      buf.org := org; buf.chg := FALSE
-    END
-  ELSE buf := NIL; org := 0; offset := 0
-  END;
-  r.buf := buf; r.org := org; r.offset := offset; r.eof := FALSE; r.res := 0
-END Set;
-
-PROCEDURE Read*(VAR r: Rider; VAR x: BYTE);
-VAR offset: INTEGER; buf: Buffer;
-BEGIN
-  buf := r.buf; offset := r.offset;
-  IF r.org # buf.org THEN
-    Set(r, buf.f, r.org + offset); buf := r.buf; offset := r.offset
-  END;
-  IF (offset < buf.size) THEN
-    x := SYSTEM.VAL(BYTE, buf.data[offset]); r.offset := offset + 1
-  ELSIF r.org + offset < buf.f.len THEN
-    Set(r, r.buf.f, r.org + offset);
-    x := SYSTEM.VAL(BYTE, r.buf.data[0]); r.offset := 1
-  ELSE x := 0; r.eof := TRUE
-  END
-END Read;
-
-PROCEDURE ReadBytes*(VAR r: Rider; VAR x: ARRAY OF BYTE; n: INTEGER);
-VAR xpos, min, restInBuf, offset: INTEGER; buf: Buffer;
-BEGIN
-  IF n > LEN(x) THEN IdxTrap(433) END;
-  xpos := 0; buf := r.buf; offset := r.offset; (* Offset within buffer r.buf *)
-  WHILE n > 0 DO
-    IF (r.org # buf.org) OR (offset >= BufSize) THEN
-      Set(r, buf.f, r.org + offset);
-      buf := r.buf; offset := r.offset
-    END;
-    restInBuf := buf.size - offset;
-    IF restInBuf = 0 THEN r.res := n; r.eof := TRUE; RETURN
-    ELSIF n > restInBuf THEN min := restInBuf ELSE min := n END;
-    SYSTEM.MOVE(SYSTEM.ADR(buf.data) + offset, SYSTEM.ADR(x) + xpos, min);
-    INC(offset, min); r.offset := offset; INC(xpos, min); DEC(n, min)
-  END;
-  r.res := 0; r.eof := FALSE
-END ReadBytes;
-
-PROCEDURE ReadShortChar*(VAR r: Rider; VAR x: SHORTCHAR);
-BEGIN Read(r, SYSTEM.VAL(BYTE, x))
-END ReadShortChar;
-
-PROCEDURE ReadChar*(VAR r: Rider; VAR x: CHAR);
-VAR b: BYTE; y: INTEGER;
-BEGIN Read(r, b); y := b;
-  IF y > 80H THEN Read(r, b); b := SYSTEM.VAL(BYTE, b MOD 64); (* Not 1 byte *)
-    IF y DIV 32 = 6 THEN (* 2 bytes *)
-      y := y MOD 32 * 64 + b
-    ELSIF y DIV 16 = 14 THEN (* 3 bytes *)
-      y := (y MOD 16 * 64 + b) * 64;
-      Read(r, b); INC(y, b MOD 64)
-    ELSIF y DIV 8 = 30 THEN (* 4 bytes *)
-      y := (y MOD 8 * 64 + b) * 64;
-      Read(r, b); y := (y + b MOD 64) * 64;
-      Read(r, b); INC(y, b MOD 64) (*!FIXME UTF-16 surrogate pairs *)
-    ELSE y := 0
-    END
-  END;
-  x := CHR(y)
-END ReadChar;
-
-PROCEDURE Base*(VAR r: Rider): File;
-BEGIN RETURN r.buf.f
-END Base;
-
-PROCEDURE Write*(VAR r: Rider; x: BYTE);
-VAR buf: Buffer; offset: INTEGER;
-BEGIN
-  buf := r.buf; offset := r.offset;
-  IF (r.org # buf.org) OR (offset >= BufSize) THEN
-    Set(r, buf.f, r.org + offset);
-    buf := r.buf; offset := r.offset
-  END;
-  buf.data[offset] := x;
-  buf.chg := TRUE;
-  IF offset = buf.size THEN
-    INC(buf.size); INC(buf.f.len)
-  END;
-  r.offset := offset + 1; r.res := 0
-END Write;
-
-PROCEDURE WriteBytes*(VAR r: Rider; IN x: ARRAY OF BYTE; n: INTEGER);
-VAR xpos, min, restInBuf, offset: INTEGER; buf: Buffer;
-BEGIN
-  IF n > LEN(x) THEN IdxTrap(477) END;
-  xpos := 0; buf := r.buf; offset := r.offset;
-  WHILE n > 0 DO
-    IF (r.org # buf.org) OR (offset >= BufSize) THEN
-      Set(r, buf.f, r.org + offset);
-      buf := r.buf; offset := r.offset
-    END;
-    restInBuf := BufSize - offset;
-    IF n > restInBuf THEN min := restInBuf ELSE min := n END;
-    SYSTEM.MOVE(SYSTEM.ADR(x) + xpos, SYSTEM.ADR(buf.data) + offset, min);
-    INC(offset, min); r.offset := offset;
-    IF offset > buf.size THEN buf.f.len := buf.f.len + (offset - buf.size);
-    buf.size := offset END; INC(xpos, min); DEC(n, min); buf.chg := TRUE
-  END;
-  r.res := 0
-END WriteBytes;
-
-PROCEDURE Delete*(IN name: ARRAY OF CHAR; VAR res: INTEGER);
-VAR pos: INTEGER;
-  dir, path: ARRAY 2048 OF CHAR;
-  q: ARRAY 2048 OF SHORTCHAR;
-BEGIN
-  IF name # '' THEN
-    IF HasDir(name) THEN dir := ''; path := name$
-    ELSE pos := 0; ScanPath(pos, dir);
-      MakeFileName(dir, name, path); ScanPath(pos, dir)
-    END;
-    LOOP
-      Deregister(path);
-      Utf8.Encode(path, q);
-      res := Platform.DeleteFile(q);
-      IF (res = 0) OR (dir = '') THEN RETURN
-      ELSE MakeFileName(dir, name, path); ScanPath(pos, dir)
-      END
-    END
-  ELSE res := 1
-  END
-END Delete;
-
-PROCEDURE Rename*(IN old, new: ARRAY OF CHAR; VAR res: INTEGER);
-VAR n: INTEGER;
-  fdold, fdnew: Platform.FileHandle;
-  error, ignore: Platform.ErrorCode;
-  oldidentity, newidentity: Platform.FileIdentity;
-  buf, old2, new2: ARRAY 4096 OF SHORTCHAR;
-BEGIN
-  Utf8.Encode(old, old2); Utf8.Encode(new, new2);
-  error := Platform.IdentifyByName(old2, oldidentity);
-  IF error = 0 THEN
-    error := Platform.IdentifyByName(new2, newidentity);
-    IF (error # 0) & ~Platform.SameFile(oldidentity, newidentity) THEN
-      Delete(new, error) (* work around stale nfs handles *)
-    END;
-    error := Platform.RenameFile(old2, new2);
-    (* TODO, if we already have a FileDesc for old, it ought to be updated
-       with the new workname. *)
-    IF ~Platform.DifferentFilesystems(error) THEN
-      res := error;
-      RETURN
-    ELSE
-      (* cross device link, move the file *)
-      error := Platform.OldRO(old2, fdold);
-      IF error # 0 THEN
-        res := 2;
-        RETURN
-      END;
-      error := Platform.NewFile(new2, fdnew);
-      IF error # 0 THEN
-        error := Platform.CloseFile(fdold); res := 3;
-        RETURN
-      END;
-      error := Platform.Read(fdold, SYSTEM.ADR(buf), BufSize, n);
-      WHILE n > 0 DO
-        error := Platform.Write(fdnew, SYSTEM.ADR(buf), n);
-        IF error # 0 THEN
-          ignore := Platform.CloseFile(fdold);
-          ignore := Platform.CloseFile(fdnew);
-          Err('cannot move file', NIL, error)
-        END;
-        error := Platform.Read(fdold, SYSTEM.ADR(buf), BufSize, n);
-      END;
-      ignore := Platform.CloseFile(fdold);
-      ignore := Platform.CloseFile(fdnew);
-      IF n = 0 THEN error := Platform.DeleteFile(old2); res := 0
-      ELSE Err('cannot move file', NIL, error)
-      END
-    END
-  ELSE res := 2 (* old file not found *)
-  END
-END Rename;
-
-PROCEDURE Register*(f: File);
-VAR errcode: INTEGER;
-  q: ARRAY 2048 OF SHORTCHAR;
-BEGIN
-  IF (f.state = create) & (f.registerName # '') THEN f.state := close END;
-  Close(f);
-  IF f.registerName # '' THEN
-    Deregister(f.registerName);
-    errcode := Platform.CloseFile(f.fd);
-    IF errcode = 0 THEN (* Platform.RenameFile requires a closed file *)
-      Rename(f.workName, f.registerName, errcode);
-      IF errcode = 0 THEN Utf8.Encode(f.registerName, q);
-        errcode := Platform.OldRW(q, f.fd);
-        IF errcode = 0 THEN f.workName := f.registerName;
-          f.registerName := ''; f.tempFile := FALSE;
-          RETURN
-        END
-      END
-    END;
-    Err('Could not rename temp name as register name', f, errcode)
-  END
-END Register;
-
-PROCEDURE ChangeDirectory*(IN path: ARRAY OF CHAR; VAR res: INTEGER);
-VAR q: ARRAY 2048 OF SHORTCHAR;
-BEGIN Utf8.Encode(path, q); res := Platform.ChDir(q)
-END ChangeDirectory;
-
-PROCEDURE FlipBytes(VAR src, dest: ARRAY OF BYTE);
-VAR i, j: INTEGER;
-BEGIN
-  IF ~Platform.LittleEndian THEN i := LEN(src); j := 0;
-    WHILE i > 0 DO DEC(i); dest[j] := src[i]; INC(j) END
-  ELSE SYSTEM.MOVE(SYSTEM.ADR(src), SYSTEM.ADR(dest), LEN(src))
-  END
-END FlipBytes;
-
-PROCEDURE ReadBool*(VAR R: Rider; VAR x: BOOLEAN);
-BEGIN Read(R, SYSTEM.VAL(BYTE, x))
-END ReadBool;
-
-PROCEDURE ReadSInt*(VAR R: Rider; VAR x: SHORTINT);
-VAR b: ARRAY 2 OF SHORTCHAR;
-BEGIN ReadBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 2), 2);
-  x := SHORT(ORD(b[0]) + ORD(b[1])*256)
-END ReadSInt;
-
-PROCEDURE ReadInt*(VAR R: Rider; VAR x: INTEGER);
-VAR b: ARRAY 4 OF SHORTCHAR;
-BEGIN ReadBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 4), 4);
-  x := ORD(b[0]) + ORD(b[1]) * 100H + ORD(b[2]) * 10000H +
-    ORD(b[3]) * 1000000H
-END ReadInt;
-
-PROCEDURE ReadLInt*(VAR R: Rider; VAR x: LONGINT);
-VAR b: ARRAY 8 OF SHORTCHAR; n: INTEGER; s: LONGINT;
-BEGIN ReadBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 8), 8);
-  x := ORD(b[0]); s := 100H;
-  FOR n := 1 TO 7 DO INC(x, ORD(b[n]) * s); s := s * 100H END
-END ReadLInt;
-
-PROCEDURE ReadSet*(VAR R: Rider; VAR x: SET);
-VAR b: ARRAY 4 OF SHORTCHAR;
-BEGIN ReadBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 4), 4);
-  x := SYSTEM.VAL(SET, ORD(b[0]) + ORD(b[1]) * 100H +
-    ORD(b[2]) * 10000H + ORD(b[3]) * 1000000H)
-END ReadSet;
-
-PROCEDURE ReadReal*(VAR R: Rider; VAR x: SHORTREAL);
-VAR b: ARRAY 4 OF BYTE;
-BEGIN ReadBytes(R, b, 4);
-  FlipBytes(b, SYSTEM.THISARR(SYSTEM.ADR(x), 4))
-END ReadReal;
-
-PROCEDURE ReadLReal*(VAR R: Rider; VAR x: REAL);
-VAR b: ARRAY 8 OF BYTE;
-BEGIN ReadBytes(R, b, 8);
-  FlipBytes(b, SYSTEM.THISARR(SYSTEM.ADR(x), 8))
-END ReadLReal;
-
-PROCEDURE ReadShortString*(VAR R: Rider; VAR x: ARRAY OF SHORTCHAR);
-VAR i: INTEGER; ch: SHORTCHAR;
-BEGIN i := 0; (*!FIXME code from scratch*)
-  REPEAT ReadShortChar(R, ch); x[i] := ch; INC(i) UNTIL ch = 0X
-END ReadShortString;
-
-PROCEDURE ReadString*(VAR R: Rider; VAR x: ARRAY OF CHAR);
-VAR i: INTEGER; ch: CHAR;
-BEGIN i := 0; (*!FIXME code from scratch*)
-  REPEAT ReadChar(R, ch); x[i] := ch; INC(i) UNTIL ch = 0X
-END ReadString;
-
-PROCEDURE ReadLine*(VAR R: Rider; VAR x: ARRAY OF SHORTCHAR);
-VAR i: INTEGER; ch: SHORTCHAR; b: BOOLEAN;
-BEGIN i := 0; b := FALSE;
-  REPEAT
-    ReadShortChar(R, ch);
-    IF ((ch = 0X) OR (ch = 0AX) OR (ch = 0DX)) THEN b := TRUE
-    ELSE x[i] := ch; INC(i)
-    END
-  UNTIL b
-END ReadLine;
-
-PROCEDURE ReadNum*(VAR R: Rider; VAR x: LONGINT);
-VAR n: INTEGER; b: BYTE;
-BEGIN n := 0; x := 0; Read(R, b);
-  WHILE b >= 128 DO
-    INC(x, ASH(LONG(b) - 128, n)); INC(n, 7); Read(R, b)
-  END;
-  INC(x, ASH(LONG(b) MOD 64 - LONG(b) DIV 64 * 64, n))
-END ReadNum;
-
-PROCEDURE WriteBool*(VAR R: Rider; x: BOOLEAN);
-BEGIN Write(R, SYSTEM.VAL(BYTE, x))
-END WriteBool;
-
-PROCEDURE WriteShortChar*(VAR R: Rider; x: SHORTCHAR);
-BEGIN Write(R, SYSTEM.VAL(BYTE, x))
-END WriteShortChar;
-
-PROCEDURE WriteChar*(VAR R: Rider; c: CHAR);
-VAR i, L: INTEGER;
-  q: ARRAY 5 OF SHORTCHAR;
-BEGIN
-  Utf8.EncodeChar(c, q, L); i := 0;
-  WHILE i # L DO Write(R, SYSTEM.VAL(BYTE, q[i])); INC(i) END
-END WriteChar;
-
-PROCEDURE WriteSInt*(VAR R: Rider; x: SHORTINT);
-VAR b: ARRAY 2 OF SHORTCHAR;
-BEGIN b[0] := SHORT(CHR(x)); b[1] := SHORT(CHR(x DIV 256));
-  WriteBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 2), 2)
-END WriteSInt;
-
-PROCEDURE WriteInt*(VAR R: Rider; x: INTEGER);
-VAR b: ARRAY 4 OF SHORTCHAR;
-BEGIN b[0] := SHORT(CHR(x)); b[1] := SHORT(CHR(x DIV 100H));
-  b[2] := SHORT(CHR(x DIV 10000H)); b[3] := SHORT(CHR(x DIV 1000000H));
-  WriteBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 4), 4)
-END WriteInt;
-
-PROCEDURE WriteLInt*(VAR R: Rider; x: LONGINT);
-VAR b: ARRAY 8 OF SHORTCHAR; n: INTEGER; s: LONGINT;
-BEGIN b[0] := SHORT(CHR(x)); s := 100H;
-  FOR n := 0 TO 7 DO b[n] := SHORT(CHR(x DIV s)); s := s*100H END;
-  WriteBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 8), 8)
-END WriteLInt;
-
-PROCEDURE WriteSet*(VAR R: Rider; x: SET);
-VAR b: ARRAY 4 OF SHORTCHAR; i: INTEGER;
-BEGIN i := SYSTEM.VAL(INTEGER, x);
-  b[0] := SHORT(CHR(i)); b[1] := SHORT(CHR(i DIV 100H));
-  b[2] := SHORT(CHR(i DIV 10000H)); b[3] := SHORT(CHR(i DIV 1000000H));
-  WriteBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 4), 4)
-END WriteSet;
-
-PROCEDURE WriteReal*(VAR R: Rider; x: SHORTREAL);
-VAR b: ARRAY 4 OF BYTE;
-BEGIN FlipBytes(SYSTEM.THISARR(SYSTEM.ADR(x), 4), b);
-  WriteBytes(R, b, 4)
-END WriteReal;
-
-PROCEDURE WriteLReal*(VAR R: Rider; x: REAL);
-VAR b: ARRAY 8 OF BYTE;
-BEGIN FlipBytes(SYSTEM.THISARR(SYSTEM.ADR(x), 8), b);
-  WriteBytes(R, b, 8)
-END WriteLReal;
-
-PROCEDURE WriteShortString*(VAR R: Rider; IN s: ARRAY OF SHORTCHAR);
-VAR i: INTEGER;
-BEGIN i := 0; WHILE s[i] # 0X DO INC(i) END;
-  WriteBytes(R, SYSTEM.THISARR(SYSTEM.ADR(s), LEN(s)), i + 1)
-END WriteShortString;
-
-PROCEDURE WriteString*(VAR R: Rider; IN s: ARRAY OF CHAR);
-VAR i: INTEGER;
-BEGIN i := -1;
-  REPEAT INC(i); WriteChar(R, s[i]) UNTIL (i = LEN(s)) OR (s[i] = 0X)
-END WriteString;
-
-PROCEDURE WriteNum*(VAR R: Rider; x: LONGINT);
-BEGIN
-  WHILE (x < - 64) OR (x > 63) DO
-    Write(R, SYSTEM.VAL(BYTE, x MOD 128 + 128)); x := x DIV 128
-  END;
-  Write(R, SYSTEM.VAL(BYTE, x MOD 128))
-END WriteNum;
-
-PROCEDURE GetName*(f: File; VAR name: ARRAY OF CHAR);
-BEGIN name := f.workName$
-END GetName;
-
-PROCEDURE Finalize(o: SYSTEM.PTR);
-VAR f: File; res: INTEGER;
-  q: ARRAY 2048 OF SHORTCHAR;
-BEGIN f := SYSTEM.VAL(File, o);
-  IF f.fd # Platform.InvalidHandleValue() THEN
-    CloseOSFile(f);
-    IF f.tempFile THEN
-      Utf8.Encode(f.workName, q);
-      res := Platform.DeleteFile(q)
-    END
-  END
-END Finalize;
-
-PROCEDURE SetSearchPath*(IN path: ARRAY OF CHAR);
-BEGIN SearchPath := path$
-END SetSearchPath;
-
-PROCEDURE Init;
-VAR q: ARRAY 2048 OF SHORTCHAR;
-BEGIN tempno := -1; Heap.FileCount := 0; SearchPath := '';
-  Platform.GetEnv('HOME', q); Utf8.Decode(q, home);
-END Init;
-
-BEGIN
-  Init
-END Files.
+MODULE Files;
+(** Standard data type input-output
+
+    Little Endian,
+    SInt: 2 bytes, Int: 4 bytes, LInt: 8 bytes
+    ORD({0}) = 1,
+    FALSE = 0, TRUE = 1
+    IEEE Real Format,
+    Null-terminated strings,
+    compact numbers according to M. Odersky *)
+
+IMPORT SYSTEM, Platform, Heap, Strings, Out, Utf8;
+
+CONST
+  PathDelimiter = Platform.PathDelimiter;
+  PathSeparator = Platform.PathSeparator;
+
+  NumBufs = 4;
+  BufSize = 4096;
+
+  (* No file states, used when FileDesc.fd = Platform.InvalidHandleValue() *)
+  open   = 0; (* OS File has been opened *)
+  create = 1; (* OS file needs to be created *)
+  close  = 2; (* Flag used by Files.Register to tell Create to create the file
+                 using it's registerName directly, rather than to create a
+                 temporary file: i.e. since we're closing and all data is still
+                 in buffers bypass writing to temp file and then renaming and
+                 just write directly to final register name *)
+
+TYPE
+  SBYTE* = BYTE;
+  BYTE* = UBYTE;
+
+  FileName = ARRAY 256 OF CHAR;
+  File* = POINTER TO FileDesc;
+  Buffer = POINTER TO BufDesc;
+
+  FileDesc = RECORD
+    workName, registerName: FileName;
+    tempFile: BOOLEAN;
+    identity: Platform.FileIdentity;
+    fd-: Platform.FileHandle;
+    len, pos: LONGINT;
+    bufs: ARRAY NumBufs OF Buffer;
+    swapper, state: SHORTINT;
+    next: POINTER [notag] TO FileDesc
+  END;
+
+  BufDesc = RECORD
+    f: File;
+    chg: BOOLEAN;
+    org: LONGINT;
+    size: INTEGER;
+    data: ARRAY BufSize OF SBYTE
+  END;
+
+  Rider* = RECORD
+    res*: INTEGER; (* Residue (byte count not read) at eof of ReadBytes *)
+    eof*: BOOLEAN;
+    buf: Buffer;
+    org: LONGINT; (* File offset of block containing current position *)
+    offset: INTEGER (* Current position offset within block at org. *)
+  END;
+
+VAR
+  (* Array of files backed by an OS file: open, registered or temporary. *)
+  files: POINTER [notag] TO FileDesc;
+
+  tempno: INTEGER;
+  home: ARRAY 1024 OF CHAR;
+  SearchPath: ARRAY 4096 OF CHAR;
+
+PROCEDURE -IdxTrap(pos: INTEGER) '__HALT(-1, "Files.Mod", pos)';
+
+PROCEDURE^ Finalize(o: SYSTEM.PTR);
+
+PROCEDURE Err(IN s: ARRAY OF CHAR; f: File; errcode: Platform.ErrorCode);
+BEGIN
+  Out.Ln; Out.String('-- '); Out.String(s); Out.String(': ');
+  IF f # NIL THEN
+    IF f.registerName # '' THEN Out.String(f.registerName)
+    ELSE Out.String(f.workName)
+    END;
+    IF f.fd # 0 THEN Out.String(' f.fd = '); Out.Int(f.fd, 1) END
+  END;
+  IF errcode # 0 THEN Out.String(' errcode = '); Out.Int(errcode, 1) END;
+  Out.Ln;
+  HALT(99)
+END Err;
+
+PROCEDURE MakeFileName(IN dir, name: ARRAY OF CHAR; VAR dest: ARRAY OF CHAR);
+VAR i, j: INTEGER;
+BEGIN i := 0; j := 0;
+  WHILE dir[i] # 0X DO dest[i] := dir[i]; INC(i) END;
+  IF dest[i-1] # PathDelimiter THEN dest[i] := PathDelimiter; INC(i) END;
+  WHILE name[j] # 0X DO dest[i] := name[j]; INC(i); INC(j) END;
+  dest[i] := 0X
+END MakeFileName;
+
+PROCEDURE GetTempName(IN finalName: ARRAY OF CHAR; VAR name: ARRAY OF CHAR);
+VAR n, i: INTEGER;
+  q: ARRAY 256 OF SHORTCHAR;
+BEGIN INC(tempno); Platform.GetTempPath(q); Utf8.Decode(q, name);
+  i := 0; WHILE name[i] # 0X DO INC(i) END;
+
+  name[i] := 'o'; INC(i); name[i] := 'b'; INC(i); name[i] := 'e'; INC(i);
+  name[i] := 'r'; INC(i); name[i] := 'o'; INC(i); name[i] := 'n'; INC(i);
+  name[i] := '.'; INC(i); n := tempno;
+  REPEAT name[i] := CHR(n MOD 10 + 30H); n := n DIV 10; INC(i) UNTIL n = 0;
+
+  name[i] := '.'; INC(i); n := Platform.PID;
+  REPEAT name[i] := CHR(n MOD 10 + 30H); n := n DIV 10; INC(i) UNTIL n = 0;
+  name[i] := 0X
+END GetTempName;
+
+(* When registering a file, it may turn out that the name we want to use
+   is aready in use by another File. E.g. the compiler opens and reads
+   an existing symbol file if present before creating an updated one.
+   When this happens on Windows, creation of the new file will be blocked
+   by the presence of the old one because it is in a open state. Further,
+   on both Unix and Windows systems we want behaviour to match that of
+   a real Oberon system, where registering the new file has the effect of
+   unregistering the old file. To simulate this we need to change the old
+   Files.File back to a temp file. *)
+PROCEDURE Deregister(IN name: ARRAY OF CHAR);
+VAR identity: Platform.FileIdentity;
+  osfile: File;
+  error: Platform.ErrorCode;
+  q, s: ARRAY 2048 OF SHORTCHAR;
+BEGIN
+  Utf8.Encode(name, q);
+  IF Platform.IdentifyByName(q, identity) = 0 THEN
+    (* The name we are registering is an already existing file. *)
+    osfile := files;
+    WHILE (osfile # NIL) & ~Platform.SameFile(osfile.identity, identity) DO
+      osfile := osfile.next
+    END;
+    IF osfile # NIL THEN
+      (* osfile is the FileDesc corresponding to the file name we are hoping
+         to register. Turn it into a temporary file. *)
+      ASSERT(~osfile.tempFile); ASSERT(osfile.fd >= 0);
+      osfile.registerName := osfile.workName;
+      GetTempName(osfile.registerName, osfile.workName);
+      osfile.tempFile := TRUE;
+      error := Platform.CloseFile(osfile.fd);
+      osfile.state := close;
+      Utf8.Encode(osfile.registerName, q);
+      Utf8.Encode(osfile.workName, s);
+      error := Platform.RenameFile(q, s);
+      IF error # 0 THEN
+        Err('Could not rename previous version of file being registered',
+          osfile, error)
+      END
+    END
+  END
+END Deregister;
+
+(** Makes sure there is an OS file backing this Oberon file.
+    Used when more data has been written to an unregistered new file than
+    buffers can hold, or when registering a new file whose data is all in
+    buffers. *)
+PROCEDURE Create(f: File);
+VAR done: BOOLEAN;
+  error: Platform.ErrorCode;
+  err: ARRAY 32 OF CHAR;
+  q: ARRAY 2048 OF SHORTCHAR;
+BEGIN
+  IF f.fd = Platform.InvalidHandleValue() THEN
+    IF f.state = create THEN
+      (* New file with enough data written to exceed buffers, so we need to
+         create a temporary file to back it. *) 
+      GetTempName(f.registerName, f.workName); f.tempFile := TRUE
+    ELSE
+      ASSERT(f.state = close);
+      (* New file with all data in buffers being registered. No need for a
+         temp file, will just write the buffers to the registerName. *)
+      Deregister(f.registerName);
+      f.workName := f.registerName; f.registerName := ''; f.tempFile := FALSE
+    END;
+    (* Unlink first to avoid stale NFS handles and to avoid reuse of inodes *)
+    Utf8.Encode(f.workName, q);
+    error := Platform.DeleteFile(q);
+
+    error := Platform.NewFile(q, f.fd);
+    done := error = 0;
+    IF done THEN
+      (* Link this file into the list of OS backed files. *)
+      f.next := files; files := f;
+      INC(Heap.FileCount);
+      Heap.RegisterFinalizer(f, Finalize);
+      f.state := open;
+      f.pos   := 0;
+      error   := Platform.Identify(f.fd, f.identity);
+    ELSE
+      IF Platform.NoSuchDirectory(error) THEN err := 'no such directory'
+      ELSIF Platform.TooManyFiles(error) THEN err := 'too many files open'
+      ELSE err := 'file not created'
+      END;
+      Err(err, f, error)
+    END
+  END
+END Create;
+
+PROCEDURE Flush(buf: Buffer);
+VAR error: Platform.ErrorCode;
+  f: File;
+BEGIN
+  IF buf.chg THEN f := buf.f; Create(f);
+    IF buf.org # f.pos THEN
+      error := Platform.Seek(f.fd, buf.org, Platform.SeekSet)
+    END;
+    error := Platform.Write(f.fd, SYSTEM.ADR(buf.data), buf.size);
+    IF error # 0 THEN Err('error writing file', f, error) END;
+    f.pos := buf.org + buf.size; buf.chg := FALSE;
+    (* Update identity with new modification time. *)
+    error := Platform.Identify(f.fd, f.identity);
+    IF error # 0 THEN Err('error identifying file', f, error) END
+  END
+END Flush;
+
+PROCEDURE CloseOSFile(f: File);
+(* Close the OS file handle and remove f from 'files' *)
+VAR prev: File; error: Platform.ErrorCode;
+BEGIN
+  IF files = f THEN files := f.next
+  ELSE
+    prev := files;
+    WHILE (prev # NIL) & (prev.next # f) DO prev := prev.next END;
+    IF prev.next # NIL THEN prev.next := f.next END
+  END;
+  error := Platform.CloseFile(f.fd);
+  f.fd := Platform.InvalidHandleValue(); f.state := create; DEC(Heap.FileCount)
+END CloseOSFile;
+
+PROCEDURE Close*(f: File);
+VAR i: INTEGER;
+BEGIN
+  IF (f.state # create) OR (f.registerName # '') THEN
+    Create(f); i := 0;
+    WHILE (i < NumBufs) & (f.bufs[i] # NIL) DO Flush(f.bufs[i]); INC(i) END
+  END
+END Close;
+
+PROCEDURE Length*(f: File): LONGINT;
+BEGIN RETURN f.len END Length;
+
+PROCEDURE New*(IN name: ARRAY OF CHAR): File;
+VAR f: File;
+BEGIN
+  NEW(f); f.workName := ''; f.registerName := name$;
+  f.fd := Platform.InvalidHandleValue(); f.state := create;
+  f.len := 0; f.pos := 0; f.swapper := -1 ;
+RETURN f END New;
+
+PROCEDURE ScanPath(VAR pos: INTEGER; VAR dir: ARRAY OF CHAR);
+(* Extract next individual directory from searchpath starting at pos,
+   updating pos and returning dir.
+   Supports ~, ~user and blanks inside path *)
+VAR i: INTEGER; ch: CHAR;
+BEGIN
+  i := 0;
+  IF SearchPath = '' THEN (* Default search path is the current directory *)
+    IF pos = 0 THEN dir[0] := '.'; i := 1; INC(pos) END
+  ELSE
+    ch := SearchPath[pos];
+    WHILE (ch = ' ') OR (ch = PathSeparator) DO
+      INC(pos); ch := SearchPath[pos]
+    END;
+    IF ch = '~' THEN
+      INC(pos); ch := SearchPath[pos];
+      WHILE home[i] # 0X DO dir[i] := home[i]; INC(i) END;
+      IF (ch # PathDelimiter) & (ch # 0X) & (ch # PathSeparator) & (ch # ' ')
+      THEN WHILE (i > 0) & (dir[i - 1] # PathDelimiter) DO DEC(i) END
+      END
+    END;
+    WHILE (ch # 0X) & (ch # PathSeparator) DO
+      dir[i] := ch; INC(i); INC(pos); ch := SearchPath[pos]
+    END;
+    WHILE (i > 0) & (dir[i - 1] = ' ') DO DEC(i) END
+  END;
+  dir[i] := 0X
+END ScanPath;
+
+PROCEDURE HasDir(IN name: ARRAY OF CHAR): BOOLEAN;
+VAR i: INTEGER; ch: CHAR;
+BEGIN i := 0; ch := name[0];
+  WHILE (ch # 0X) & (ch # PathDelimiter) DO INC(i); ch := name[i] END ;
+RETURN ch = PathDelimiter END HasDir;
+
+PROCEDURE CacheEntry(identity: Platform.FileIdentity): File;
+VAR f: File; i: INTEGER; error: Platform.ErrorCode;
+BEGIN f := files;
+  WHILE f # NIL DO
+    IF Platform.SameFile(identity, f.identity) THEN
+      IF ~Platform.SameFileTime(identity, f.identity) THEN i := 0;
+        WHILE i < NumBufs DO
+          IF f.bufs[i] # NIL THEN f.bufs[i].org := -1; f.bufs[i] := NIL END;
+          INC(i)
+        END;
+        f.swapper := -1; f.identity := identity;
+        error := Platform.FileSize(f.fd, f.len)
+      END;
+      RETURN f
+    END;
+    f := f.next
+  END;
+  RETURN NIL
+END CacheEntry;
+
+PROCEDURE Old*(IN name: ARRAY OF CHAR): File;
+VAR f: File;
+  fd: Platform.FileHandle;
+  pos: INTEGER;
+  done: BOOLEAN;
+  dir, path: ARRAY 256 OF CHAR;
+  error: Platform.ErrorCode;
+  identity: Platform.FileIdentity;
+  q: ARRAY 4096 OF SHORTCHAR;
+BEGIN
+  IF name # '' THEN
+    IF HasDir(name) THEN dir := ''; path := name$
+    ELSE pos := 0; ScanPath(pos, dir);
+      MakeFileName(dir, name, path); ScanPath(pos, dir)
+    END;
+    LOOP Utf8.Encode(path, q);
+      error := Platform.OldRW(q, fd); done := error = 0;
+      IF ~done & Platform.TooManyFiles(error) THEN
+        Err('too many files open', f, error)
+      END;
+      IF ~done & Platform.Inaccessible(error) THEN
+        error := Platform.OldRO(q, fd); done := error = 0
+      END;
+      IF ~done & ~Platform.Absent(error) THEN
+        Out.String('Warning: Files.Old '); Out.String(name);
+        Out.String(' error = '); Out.Int(error, 0); Out.Ln
+      END;
+      IF done THEN
+        error := Platform.Identify(fd, identity);
+        f := CacheEntry(identity);
+        IF f # NIL THEN
+          error := Platform.CloseFile(fd); (* fd not needed, f.fd is used *)
+          RETURN f
+        ELSE NEW(f); Heap.RegisterFinalizer(f, Finalize);
+          f.fd := fd; f.state := open; f.pos := 0; f.swapper := -1;
+          error := Platform.FileSize(fd, f.len);
+          f.workName := name$; f.registerName := ''; f.tempFile := FALSE;
+          f.identity := identity;
+          f.next := files; files := f; INC(Heap.FileCount);
+          RETURN f
+        END
+      ELSIF dir = '' THEN RETURN NIL
+      ELSE MakeFileName(dir, name, path); ScanPath(pos, dir)
+      END
+    END
+  ELSE RETURN NIL
+  END
+END Old;
+
+PROCEDURE Purge*(f: File);
+VAR i: INTEGER;
+  identity: Platform.FileIdentity;
+  error: Platform.ErrorCode;
+BEGIN i := 0;
+  WHILE i < NumBufs DO
+    IF f.bufs[i] # NIL THEN f.bufs[i].org := -1; f.bufs[i] := NIL END;
+    INC(i)
+  END;
+  IF f.fd # Platform.InvalidHandleValue() THEN
+    error := Platform.TruncateFile(f.fd, 0);
+    error := Platform.Seek(f.fd, 0, Platform.SeekSet)
+  END;
+  f.pos := 0; f.len := 0; f.swapper := -1;
+  error := Platform.Identify(f.fd, identity);
+  Platform.SetMTime(f.identity, identity)
+END Purge;
+
+PROCEDURE GetDate*(f: File; VAR t, d: INTEGER);
+VAR identity: Platform.FileIdentity;
+  error: Platform.ErrorCode;
+BEGIN Create(f); error := Platform.Identify(f.fd, identity);
+  Platform.MTimeAsClock(identity, t, d)
+END GetDate;
+
+PROCEDURE Pos*(VAR r: Rider): INTEGER;
+BEGIN RETURN SHORT(r.org + r.offset)
+END Pos;
+
+PROCEDURE Set*(VAR r: Rider; f: File; pos: LONGINT);
+VAR org: LONGINT;
+  offset, i, n: INTEGER;
+  buf: Buffer;
+  error: Platform.ErrorCode;
+BEGIN
+  IF f # NIL THEN
+    IF pos > f.len THEN pos := f.len ELSIF pos < 0 THEN pos := 0 END;
+    offset := SHORT(pos MOD BufSize); org := pos - offset; i := 0;
+    WHILE (i < NumBufs) & (f.bufs[i] # NIL) & (org # f.bufs[i].org) DO
+      INC(i)
+    END;
+    IF i < NumBufs THEN
+      IF f.bufs[i] = NIL THEN
+        NEW(buf); buf.chg := FALSE; buf.org := -1; buf.f := f; f.bufs[i] := buf
+      ELSE buf := f.bufs[i]
+      END
+    ELSE f.swapper := SHORT((f.swapper + 1) MOD NumBufs);
+      buf := f.bufs[f.swapper];
+      Flush(buf)
+    END;
+    IF buf.org # org THEN
+      IF org = f.len THEN buf.size := 0
+      ELSE Create(f);
+        IF f.pos # org THEN
+          error := Platform.Seek(f.fd, org, Platform.SeekSet)
+        END;
+        error := Platform.ReadBuf(f.fd, buf.data, n);
+        IF error # 0 THEN Err('read from file not done', f, error) END;
+        f.pos := org + n;
+        buf.size := n
+      END;
+      buf.org := org; buf.chg := FALSE
+    END
+  ELSE buf := NIL; org := 0; offset := 0
+  END;
+  r.buf := buf; r.org := org; r.offset := offset; r.eof := FALSE; r.res := 0
+END Set;
+
+PROCEDURE Read*(VAR r: Rider; VAR x: BYTE);
+VAR offset: INTEGER; buf: Buffer;
+BEGIN
+  buf := r.buf; offset := r.offset;
+  IF r.org # buf.org THEN
+    Set(r, buf.f, r.org + offset); buf := r.buf; offset := r.offset
+  END;
+  IF (offset < buf.size) THEN
+    x := SYSTEM.VAL(BYTE, buf.data[offset]); r.offset := offset + 1
+  ELSIF r.org + offset < buf.f.len THEN
+    Set(r, r.buf.f, r.org + offset);
+    x := SYSTEM.VAL(BYTE, r.buf.data[0]); r.offset := 1
+  ELSE x := 0; r.eof := TRUE
+  END
+END Read;
+
+PROCEDURE ReadBytes*(VAR r: Rider; VAR x: ARRAY OF BYTE; n: INTEGER);
+VAR xpos, min, restInBuf, offset: INTEGER; buf: Buffer;
+BEGIN
+  IF n > LEN(x) THEN IdxTrap(433) END;
+  xpos := 0; buf := r.buf; offset := r.offset; (* Offset within buffer r.buf *)
+  WHILE n > 0 DO
+    IF (r.org # buf.org) OR (offset >= BufSize) THEN
+      Set(r, buf.f, r.org + offset);
+      buf := r.buf; offset := r.offset
+    END;
+    restInBuf := buf.size - offset;
+    IF restInBuf = 0 THEN r.res := n; r.eof := TRUE; RETURN
+    ELSIF n > restInBuf THEN min := restInBuf ELSE min := n END;
+    SYSTEM.MOVE(SYSTEM.ADR(buf.data) + offset, SYSTEM.ADR(x) + xpos, min);
+    INC(offset, min); r.offset := offset; INC(xpos, min); DEC(n, min)
+  END;
+  r.res := 0; r.eof := FALSE
+END ReadBytes;
+
+PROCEDURE ReadShortChar*(VAR r: Rider; VAR x: SHORTCHAR);
+BEGIN Read(r, SYSTEM.VAL(BYTE, x))
+END ReadShortChar;
+
+PROCEDURE ReadChar*(VAR r: Rider; VAR x: CHAR);
+VAR b: BYTE; y: INTEGER;
+BEGIN Read(r, b); y := b;
+  IF y > 80H THEN Read(r, b); b := SYSTEM.VAL(BYTE, b MOD 64); (* Not 1 byte *)
+    IF y DIV 32 = 6 THEN (* 2 bytes *)
+      y := y MOD 32 * 64 + b
+    ELSIF y DIV 16 = 14 THEN (* 3 bytes *)
+      y := (y MOD 16 * 64 + b) * 64;
+      Read(r, b); INC(y, b MOD 64)
+    ELSIF y DIV 8 = 30 THEN (* 4 bytes *)
+      y := (y MOD 8 * 64 + b) * 64;
+      Read(r, b); y := (y + b MOD 64) * 64;
+      Read(r, b); INC(y, b MOD 64) (*!FIXME UTF-16 surrogate pairs *)
+    ELSE y := 0
+    END
+  END;
+  x := CHR(y)
+END ReadChar;
+
+PROCEDURE Base*(VAR r: Rider): File;
+BEGIN RETURN r.buf.f
+END Base;
+
+PROCEDURE Write*(VAR r: Rider; x: BYTE);
+VAR buf: Buffer; offset: INTEGER;
+BEGIN
+  buf := r.buf; offset := r.offset;
+  IF (r.org # buf.org) OR (offset >= BufSize) THEN
+    Set(r, buf.f, r.org + offset);
+    buf := r.buf; offset := r.offset
+  END;
+  buf.data[offset] := x;
+  buf.chg := TRUE;
+  IF offset = buf.size THEN
+    INC(buf.size); INC(buf.f.len)
+  END;
+  r.offset := offset + 1; r.res := 0
+END Write;
+
+PROCEDURE WriteBytes*(VAR r: Rider; IN x: ARRAY OF BYTE; n: INTEGER);
+VAR xpos, min, restInBuf, offset: INTEGER; buf: Buffer;
+BEGIN
+  IF n > LEN(x) THEN IdxTrap(477) END;
+  xpos := 0; buf := r.buf; offset := r.offset;
+  WHILE n > 0 DO
+    IF (r.org # buf.org) OR (offset >= BufSize) THEN
+      Set(r, buf.f, r.org + offset);
+      buf := r.buf; offset := r.offset
+    END;
+    restInBuf := BufSize - offset;
+    IF n > restInBuf THEN min := restInBuf ELSE min := n END;
+    SYSTEM.MOVE(SYSTEM.ADR(x) + xpos, SYSTEM.ADR(buf.data) + offset, min);
+    INC(offset, min); r.offset := offset;
+    IF offset > buf.size THEN buf.f.len := buf.f.len + (offset - buf.size);
+    buf.size := offset END; INC(xpos, min); DEC(n, min); buf.chg := TRUE
+  END;
+  r.res := 0
+END WriteBytes;
+
+PROCEDURE Delete*(IN name: ARRAY OF CHAR; VAR res: INTEGER);
+VAR pos: INTEGER;
+  dir, path: ARRAY 2048 OF CHAR;
+  q: ARRAY 2048 OF SHORTCHAR;
+BEGIN
+  IF name # '' THEN
+    IF HasDir(name) THEN dir := ''; path := name$
+    ELSE pos := 0; ScanPath(pos, dir);
+      MakeFileName(dir, name, path); ScanPath(pos, dir)
+    END;
+    LOOP
+      Deregister(path);
+      Utf8.Encode(path, q);
+      res := Platform.DeleteFile(q);
+      IF (res = 0) OR (dir = '') THEN RETURN
+      ELSE MakeFileName(dir, name, path); ScanPath(pos, dir)
+      END
+    END
+  ELSE res := 1
+  END
+END Delete;
+
+PROCEDURE Rename*(IN old, new: ARRAY OF CHAR; VAR res: INTEGER);
+VAR n: INTEGER;
+  fdold, fdnew: Platform.FileHandle;
+  error, ignore: Platform.ErrorCode;
+  oldidentity, newidentity: Platform.FileIdentity;
+  buf, old2, new2: ARRAY 4096 OF SHORTCHAR;
+BEGIN
+  Utf8.Encode(old, old2); Utf8.Encode(new, new2);
+  error := Platform.IdentifyByName(old2, oldidentity);
+  IF error = 0 THEN
+    error := Platform.IdentifyByName(new2, newidentity);
+    IF (error # 0) & ~Platform.SameFile(oldidentity, newidentity) THEN
+      Delete(new, error) (* work around stale nfs handles *)
+    END;
+    error := Platform.RenameFile(old2, new2);
+    (* TODO, if we already have a FileDesc for old, it ought to be updated
+       with the new workname. *)
+    IF ~Platform.DifferentFilesystems(error) THEN
+      res := error;
+      RETURN
+    ELSE
+      (* cross device link, move the file *)
+      error := Platform.OldRO(old2, fdold);
+      IF error # 0 THEN
+        res := 2;
+        RETURN
+      END;
+      error := Platform.NewFile(new2, fdnew);
+      IF error # 0 THEN
+        error := Platform.CloseFile(fdold); res := 3;
+        RETURN
+      END;
+      error := Platform.Read(fdold, SYSTEM.ADR(buf), BufSize, n);
+      WHILE n > 0 DO
+        error := Platform.Write(fdnew, SYSTEM.ADR(buf), n);
+        IF error # 0 THEN
+          ignore := Platform.CloseFile(fdold);
+          ignore := Platform.CloseFile(fdnew);
+          Err('cannot move file', NIL, error)
+        END;
+        error := Platform.Read(fdold, SYSTEM.ADR(buf), BufSize, n);
+      END;
+      ignore := Platform.CloseFile(fdold);
+      ignore := Platform.CloseFile(fdnew);
+      IF n = 0 THEN error := Platform.DeleteFile(old2); res := 0
+      ELSE Err('cannot move file', NIL, error)
+      END
+    END
+  ELSE res := 2 (* old file not found *)
+  END
+END Rename;
+
+PROCEDURE Register*(f: File);
+VAR errcode: INTEGER;
+  q: ARRAY 2048 OF SHORTCHAR;
+BEGIN
+  IF (f.state = create) & (f.registerName # '') THEN f.state := close END;
+  Close(f);
+  IF f.registerName # '' THEN
+    Deregister(f.registerName);
+    errcode := Platform.CloseFile(f.fd);
+    IF errcode = 0 THEN (* Platform.RenameFile requires a closed file *)
+      Rename(f.workName, f.registerName, errcode);
+      IF errcode = 0 THEN Utf8.Encode(f.registerName, q);
+        errcode := Platform.OldRW(q, f.fd);
+        IF errcode = 0 THEN f.workName := f.registerName;
+          f.registerName := ''; f.tempFile := FALSE;
+          RETURN
+        END
+      END
+    END;
+    Err('Could not rename temp name as register name', f, errcode)
+  END
+END Register;
+
+PROCEDURE ChangeDirectory*(IN path: ARRAY OF CHAR; VAR res: INTEGER);
+VAR q: ARRAY 2048 OF SHORTCHAR;
+BEGIN Utf8.Encode(path, q); res := Platform.ChDir(q)
+END ChangeDirectory;
+
+PROCEDURE FlipBytes(VAR src, dest: ARRAY OF BYTE);
+VAR i, j: INTEGER;
+BEGIN
+  IF ~Platform.LittleEndian THEN i := LEN(src); j := 0;
+    WHILE i > 0 DO DEC(i); dest[j] := src[i]; INC(j) END
+  ELSE SYSTEM.MOVE(SYSTEM.ADR(src), SYSTEM.ADR(dest), LEN(src))
+  END
+END FlipBytes;
+
+PROCEDURE ReadBool*(VAR R: Rider; VAR x: BOOLEAN);
+BEGIN Read(R, SYSTEM.VAL(BYTE, x))
+END ReadBool;
+
+PROCEDURE ReadSInt*(VAR R: Rider; VAR x: SHORTINT);
+VAR b: ARRAY 2 OF SHORTCHAR;
+BEGIN ReadBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 2), 2);
+  x := SHORT(ORD(b[0]) + ORD(b[1])*256)
+END ReadSInt;
+
+PROCEDURE ReadInt*(VAR R: Rider; VAR x: INTEGER);
+VAR b: ARRAY 4 OF SHORTCHAR;
+BEGIN ReadBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 4), 4);
+  x := ORD(b[0]) + ORD(b[1]) * 100H + ORD(b[2]) * 10000H +
+    ORD(b[3]) * 1000000H
+END ReadInt;
+
+PROCEDURE ReadLInt*(VAR R: Rider; VAR x: LONGINT);
+VAR b: ARRAY 8 OF SHORTCHAR; n: INTEGER; s: LONGINT;
+BEGIN ReadBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 8), 8);
+  x := ORD(b[0]); s := 100H;
+  FOR n := 1 TO 7 DO INC(x, ORD(b[n]) * s); s := s * 100H END
+END ReadLInt;
+
+PROCEDURE ReadSet*(VAR R: Rider; VAR x: SET);
+VAR b: ARRAY 4 OF SHORTCHAR;
+BEGIN ReadBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 4), 4);
+  x := SYSTEM.VAL(SET, ORD(b[0]) + ORD(b[1]) * 100H +
+    ORD(b[2]) * 10000H + ORD(b[3]) * 1000000H)
+END ReadSet;
+
+PROCEDURE ReadReal*(VAR R: Rider; VAR x: SHORTREAL);
+VAR b: ARRAY 4 OF BYTE;
+BEGIN ReadBytes(R, b, 4);
+  FlipBytes(b, SYSTEM.THISARR(SYSTEM.ADR(x), 4))
+END ReadReal;
+
+PROCEDURE ReadLReal*(VAR R: Rider; VAR x: REAL);
+VAR b: ARRAY 8 OF BYTE;
+BEGIN ReadBytes(R, b, 8);
+  FlipBytes(b, SYSTEM.THISARR(SYSTEM.ADR(x), 8))
+END ReadLReal;
+
+PROCEDURE ReadShortString*(VAR R: Rider; VAR x: ARRAY OF SHORTCHAR);
+VAR i: INTEGER; ch: SHORTCHAR;
+BEGIN i := 0; (*!FIXME code from scratch*)
+  REPEAT ReadShortChar(R, ch); x[i] := ch; INC(i) UNTIL ch = 0X
+END ReadShortString;
+
+PROCEDURE ReadString*(VAR R: Rider; VAR x: ARRAY OF CHAR);
+VAR i: INTEGER; ch: CHAR;
+BEGIN i := 0; (*!FIXME code from scratch*)
+  REPEAT ReadChar(R, ch); x[i] := ch; INC(i) UNTIL ch = 0X
+END ReadString;
+
+PROCEDURE ReadLine*(VAR R: Rider; VAR x: ARRAY OF SHORTCHAR);
+VAR i: INTEGER; ch: SHORTCHAR; b: BOOLEAN;
+BEGIN i := 0; b := FALSE;
+  REPEAT
+    ReadShortChar(R, ch);
+    IF ((ch = 0X) OR (ch = 0AX) OR (ch = 0DX)) THEN b := TRUE
+    ELSE x[i] := ch; INC(i)
+    END
+  UNTIL b
+END ReadLine;
+
+PROCEDURE ReadNum*(VAR R: Rider; VAR x: LONGINT);
+VAR n: INTEGER; b: BYTE;
+BEGIN n := 0; x := 0; Read(R, b);
+  WHILE b >= 128 DO
+    INC(x, ASH(LONG(b) - 128, n)); INC(n, 7); Read(R, b)
+  END;
+  INC(x, ASH(LONG(b) MOD 64 - LONG(b) DIV 64 * 64, n))
+END ReadNum;
+
+PROCEDURE WriteBool*(VAR R: Rider; x: BOOLEAN);
+BEGIN Write(R, SYSTEM.VAL(BYTE, x))
+END WriteBool;
+
+PROCEDURE WriteShortChar*(VAR R: Rider; x: SHORTCHAR);
+BEGIN Write(R, SYSTEM.VAL(BYTE, x))
+END WriteShortChar;
+
+PROCEDURE WriteChar*(VAR R: Rider; c: CHAR);
+VAR i, L: INTEGER;
+  q: ARRAY 5 OF SHORTCHAR;
+BEGIN
+  Utf8.EncodeChar(c, q, L); i := 0;
+  WHILE i # L DO Write(R, SYSTEM.VAL(BYTE, q[i])); INC(i) END
+END WriteChar;
+
+PROCEDURE WriteSInt*(VAR R: Rider; x: SHORTINT);
+VAR b: ARRAY 2 OF SHORTCHAR;
+BEGIN b[0] := SHORT(CHR(x)); b[1] := SHORT(CHR(x DIV 256));
+  WriteBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 2), 2)
+END WriteSInt;
+
+PROCEDURE WriteInt*(VAR R: Rider; x: INTEGER);
+VAR b: ARRAY 4 OF SHORTCHAR;
+BEGIN b[0] := SHORT(CHR(x)); b[1] := SHORT(CHR(x DIV 100H));
+  b[2] := SHORT(CHR(x DIV 10000H)); b[3] := SHORT(CHR(x DIV 1000000H));
+  WriteBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 4), 4)
+END WriteInt;
+
+PROCEDURE WriteLInt*(VAR R: Rider; x: LONGINT);
+VAR b: ARRAY 8 OF SHORTCHAR; n: INTEGER; s: LONGINT;
+BEGIN b[0] := SHORT(CHR(x)); s := 100H;
+  FOR n := 0 TO 7 DO b[n] := SHORT(CHR(x DIV s)); s := s*100H END;
+  WriteBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 8), 8)
+END WriteLInt;
+
+PROCEDURE WriteSet*(VAR R: Rider; x: SET);
+VAR b: ARRAY 4 OF SHORTCHAR; i: INTEGER;
+BEGIN i := SYSTEM.VAL(INTEGER, x);
+  b[0] := SHORT(CHR(i)); b[1] := SHORT(CHR(i DIV 100H));
+  b[2] := SHORT(CHR(i DIV 10000H)); b[3] := SHORT(CHR(i DIV 1000000H));
+  WriteBytes(R, SYSTEM.THISARR(SYSTEM.ADR(b), 4), 4)
+END WriteSet;
+
+PROCEDURE WriteReal*(VAR R: Rider; x: SHORTREAL);
+VAR b: ARRAY 4 OF BYTE;
+BEGIN FlipBytes(SYSTEM.THISARR(SYSTEM.ADR(x), 4), b);
+  WriteBytes(R, b, 4)
+END WriteReal;
+
+PROCEDURE WriteLReal*(VAR R: Rider; x: REAL);
+VAR b: ARRAY 8 OF BYTE;
+BEGIN FlipBytes(SYSTEM.THISARR(SYSTEM.ADR(x), 8), b);
+  WriteBytes(R, b, 8)
+END WriteLReal;
+
+PROCEDURE WriteShortString*(VAR R: Rider; IN s: ARRAY OF SHORTCHAR);
+VAR i: INTEGER;
+BEGIN i := 0; WHILE s[i] # 0X DO INC(i) END;
+  WriteBytes(R, SYSTEM.THISARR(SYSTEM.ADR(s), LEN(s)), i + 1)
+END WriteShortString;
+
+PROCEDURE WriteString*(VAR R: Rider; IN s: ARRAY OF CHAR);
+VAR i: INTEGER;
+BEGIN i := -1;
+  REPEAT INC(i); WriteChar(R, s[i]) UNTIL (i = LEN(s)) OR (s[i] = 0X)
+END WriteString;
+
+PROCEDURE WriteNum*(VAR R: Rider; x: LONGINT);
+BEGIN
+  WHILE (x < - 64) OR (x > 63) DO
+    Write(R, SYSTEM.VAL(BYTE, x MOD 128 + 128)); x := x DIV 128
+  END;
+  Write(R, SYSTEM.VAL(BYTE, x MOD 128))
+END WriteNum;
+
+PROCEDURE GetName*(f: File; VAR name: ARRAY OF CHAR);
+BEGIN name := f.workName$
+END GetName;
+
+PROCEDURE Finalize(o: SYSTEM.PTR);
+VAR f: File; res: INTEGER;
+  q: ARRAY 2048 OF SHORTCHAR;
+BEGIN f := SYSTEM.VAL(File, o);
+  IF f.fd # Platform.InvalidHandleValue() THEN
+    CloseOSFile(f);
+    IF f.tempFile THEN
+      Utf8.Encode(f.workName, q);
+      res := Platform.DeleteFile(q)
+    END
+  END
+END Finalize;
+
+PROCEDURE SetSearchPath*(IN path: ARRAY OF CHAR);
+BEGIN SearchPath := path$
+END SetSearchPath;
+
+PROCEDURE Init;
+VAR q: ARRAY 2048 OF SHORTCHAR;
+BEGIN tempno := -1; Heap.FileCount := 0; SearchPath := '';
+  Platform.GetEnv('HOME', q); Utf8.Decode(q, home);
+END Init;
+
+BEGIN
+  Init
+END Files.

src/Texts.Mod

@@ -50,13 +50,16 @@ BEGIN Files.ReadChar(R.rider, ch);
   IF R.rider.eof THEN R.eot := TRUE END
 END Read;
 
+PROCEDURE Pos*(VAR R: Reader): INTEGER;
+RETURN Files.Pos(R.rider) END Pos;
+
 PROCEDURE Next(VAR S: Scanner);
 BEGIN Files.ReadChar(S.rider, S.nextCh);
   IF ~S.rider.eof & (S.nextCh = 0AX) THEN INC(S.line) END
 END Next;
 
 PROCEDURE OpenScanner*(VAR S: Scanner; T: Text; pos: LONGINT);
-BEGIN OpenReader(S, T, pos); S.line := 1; Next(S)
+BEGIN OpenReader(S, T, pos); S.line := 0; S.nextCh := ' '
 END OpenScanner;
 
 PROCEDURE Scan*(VAR S: Scanner);

src/edit.sh

@@ -1,2 +1,2 @@
 #!/bin/bash
-vim -p FreeOberon.Mod FoStrings.Mod ../Data/Texts/ru.dat Texts.Mod OV.Mod TermBox.Mod Graph2.Mod Allegro5.Mod
+vim -p FreeOberon.Mod FoStrings.Mod ../Data/Texts/ru.dat Texts.Mod OV.Mod