(* 1---Module 06---1 *)

  PROCEDURE erasems_dos;

    VAR
      filename       : str20;
      next, i, err   : integer;
      stop           : boolean;

    (* 2---------------2 *)

    PROCEDURE erasefiles;

      VAR
        i              : integer;
        cl             : integer;

      BEGIN (* erasefiles *)
      REPEAT
        writeln;
        FOR i := 1 TO namesize DO
          IF NOT (dos_fcb^.name[i] = ' ') THEN
            write(dos_fcb^.name[i]);
        write('.');
        FOR i := 1 TO typesize DO write(dos_fcb^.extention[i]);
        cl := dos_fcb^.clusterno;
        IF (cl <= nclusters) THEN BEGIN
          next := cl;
          REPEAT
            cl := next; next := fatpointer(cl);
            setfatpointer(cl, 0);
          UNTIL ((next > nclusters) OR (next = 0)); END;
        dos_fcb^.name[1] := #$e5;
        writesector(dirsector, dirtrack, addr(dirbuffer), true);
        searchnext(filename, err); stop := break OR bioserror;
      UNTIL (err = eodirectory) OR stop;
      END; (* erasefiles *)

    (* 2---------------2 *)

    BEGIN (* erasems_dos *)
    identifyms_dos;
    IF (identity <> unidentified) THEN BEGIN
      clrscr;
      write('Erase MS-DOS files.  MS-DOS directory:');
      dirms_dos(true); writeln;
      write('File Name to Erase From MS-DOS: ');
      readln(filename); writeln; stop := false;
      IF filename = '' THEN write('Aborted, ')
      ELSE BEGIN
        searchfirst(filename, err);
        IF (err = $ff) THEN write('File Not Found, ')
        ELSE BEGIN
          write('Erasing -'); erasefiles; writeln; END;
        IF stop THEN write('Aborted, ');
        putfat; END;
      continue; END;
    END; (* erase_msdos *)

  (* 1---------------1 *)

  (********************)
  (*                  *)
  (*   main program   *)
  (*                  *)
  (********************)

  BEGIN (* transfer *)
  IF checkdriver THEN BEGIN
    clrscr; defaultdisk := bdos(25);
    REPEAT
      gotoxy(1, 5);
      write('Which Drive is the MS-DOS Disk in? ');
      read(kbd, selection);
      write(upcase(selection), ':');
      ms_dos_drive := ord(upcase(selection)) - ord('A');
      writeln;
      write('Which drive is the  CP/M  Disk in? ');
      read(kbd, cpm_drivech);
      cpm_drivech := upcase(cpm_drivech);
      write(cpm_drivech, ':');
      cpm_drive := ord(upcase(cpm_drivech)) - ord('A');
      biosselect(cpm_drive);
    UNTIL NOT bioserror;

    writeln; biosselect(defaultdisk);
    done := false; delay(1000);

    REPEAT
      selection := mainselection; clrscr;
      CASE selection OF
 '1':   writems_dos;
 '2':   readms_dos;
 '3':   dirms_dos(false);
 '4':   mapms_dos;
 '5':   dircpm(true);
 '6':   erasems_dos;
 '7':   restorefat;
 '8':   done := true;
        END; (* case *)
    UNTIL done; END;
  END. (* transfer *)