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Assembly Source File  |  1999-08-11  |  810 b   |  46 lines
  1.  
  2. ; *******************************************************
  3. ; *                            *
  4. ; *     Delphi Runtime Library                          *
  5. ; *                            *
  6. ; *    Copyright (c) 1996,98 Inprise Corporation    *
  7. ; *                            *
  8. ; *******************************************************
  9.  
  10.     INCLUDE    SE.ASM
  11.     INCLUDE    FILEIO.ASM
  12.  
  13.     .386
  14.     .MODEL    FLAT
  15.  
  16.     EXTRN    SetEndOfFile:NEAR, GetLastError:NEAR, InOutError:NEAR, SetInOutRes:NEAR
  17.  
  18.     PUBLIC    _Truncate
  19.  
  20.     .CODE
  21.  
  22. ;    PROCEDURE _Truncate( f: Text or File );
  23.  
  24. _Truncate PROC
  25.  
  26. ; ->    EAX    Pointer to file variable
  27.  
  28.     MOV    EDX,[EAX].Mode        ; check whether file is open
  29.     SUB    EDX,fmInput
  30.     CMP    EDX,fmInOut-fmInput
  31.     JA    @@fileNotOpen
  32.  
  33.     PUSH    [EAX].Handle
  34.     CALL    SetEndOfFile
  35.     DEC    EAX
  36.     JNZ    InOutError
  37.     RET
  38.  
  39. @@fileNotOpen:
  40.     MOV    EAX,103
  41.     JMP    SetInOutRes
  42.  
  43. _Truncate ENDP
  44.  
  45.     END
  46.