en:docs:dos:api:int21:23

Note: This API call is for DOS and Win16 personality only. Use Family API for portability.

2018/09/07 05:04 · prokushev · 0 Comments

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

2018/09/04 17:23 · prokushev · 0 Comments