qa.hlp (Table of Contents; Topic list)
Important Notice
The pages on this site contain documentation for very old MS-DOS software, purely for historical purposes. If you're looking for up-to-date documentation, particularly for programming, you should not rely on the information found here, as it will be woefully out of date.
Rewind
   Example  Back  Contents  Index
──────────────────────────────────────────────────────────────────────────────
 
;* Rewind - Rewinds an open file, specified by handle. See the GetFileSize
;* procedure for an example of using Function 42h to determine file size.
;*
;* Shows:   DOS Function - 42h (Set File Pointer)
;*
;* Params:  handle - File handle
;*
;* Return:  None
 
Rewind  PROC \
        handle:WORD
 
        mov     bx, handle              ; BX = file handle
        mov     ax, 4200h               ; AH = function #,
                                        ; AL = move to beginning of
        sub     cx, cx                  ;      file plus offset
        sub     dx, dx                  ; CX:DX = offset (zero)
        int     21h                     ; Move File Read/Write Pointer
        ret
 
Rewind  ENDP
                                    -♦-