en:docs:dos:api:int21:23

Note: This API call is for DOS personality only. Use Family API for portability.

2018/09/07 07:04 · prokushev

Int 21H, AH=23H

Version

1 and higher

Brief

GET FILE SIZE FOR FCB

Family API

Input

      AH = 23h
      DS:DX -> unopened FCB (see #01345), wildcards not allowed

Return

AL = status

          00h successful (matching file found)
              FCB random record field filled with size in records, rounded up
              to next full record
          FFh failed (no matching file found)

Notes

not supported by MS Windows 3.0 DOSX.EXE DOS extender
      MS-DOS returns nonsense if the FCB record number field is set to a very
        large positive number, and status FFh if negative; DR DOS returns the
        correct file size in both cases

BUG: APPEND for DOS 3.3+ corrupts DX if the file is not found

See also

AH=42h

Note

DOS API
Process manager INT 20H, INT 21H: 00H, 25H, 26H, 31H, 34H, 35H, 4CH, INT 22H, INT 27H, INT 28H
File manager INT 25H, INT 26H, INT 21H: 0DH, 0EH, 0FH, 10H, 11H, 12H, 13H, 14H, 15H, 16H, 17H, 19H, 1AH, 1BH, 1CH, 21H, 22H, 23H, 24H, 27H, 28H, 29H, 2EH, 2FH, 32H, 3305H, 36H, 39H, 3AH, 3BH
Character Device I/O INT 29H, INT 21H: 01H, 02H, 03H, 04H, 05H, 06H, 07H, 08H, 09H, 0AH, 0BH, 0AH, 0CH
Signals INT 23H, INT 24H, INT 21H: 3300H, 3301H, 3302H
Memory manager
Date and Time INT 21H: 2AH, 2BH, 2CH, 2DH
Misc INT 21H: 30H, 3306H, 3700H, 3701H, 3702H, 3703H
NLS INT 21H: 3303H, 3304H, 3800H, 3801H
2018/09/04 19:23 · prokushev

en/docs/dos/api/int21/23.txt · Last modified: 2020/12/09 02:46 by prokushev