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

2018/09/07 07:04 · prokushev

Int 21H, AH=33H, AL=01H


2 and higher


set state of extended Ctrl-C/Ctrl-Break checking

Family API


      AH = 33h
      AL = 01h
      DL = new state
                  00h off, check only on character I/O functions
                  01h on, check on all DOS functions


(Novell DOS 7) DL = old state of extended Break checks



 under DOS 3.1+ and DR DOS, this function does not use any of the
        DOS-internal stacks and may thus be called at any time

See also



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/int21/33/01.txt · Last modified: 2020/12/09 07:18 by prokushev