DOS ain't dead

DPMI - how to chain user and original RM handler? (Developers)

posted by bretjohn  , Rio Rancho, NM, 04.05.2023, 04:03

> I am trying to implement the INT 15h/AH=4Fh keyboard interrupt.
> If I detect the 4Fh in the AH I can do what I want.
> But if there is not the 4Fh (if there is f.e. AX=E820h) I have to put my
> hands off and just to call the original routine.

INT 15.4F isn't really the keyboard interrupt -- it is used to modify scancodes.
I'm trying to imagine a scenario where implementing an INT 15.4F routine in DPMI would be useful and I can't think of one. What exactly are you trying to accomplish?

Also, you will need to let the original routine process even if it's INT 15.4F but the scancode isn't the one you're trying to "trap". You may also need/want to call the original routine _before_ you do any of your own processing in case there is another handler that modifies some of the same scancodes you're trying to process (like a foreign keyboard layout driver that uses INT 15.4F instead of INT 09).

Complete thread:

• DPMI - how to chain user and original RM handler? - Laaca, 29.04.2023, 00:41
  • DPMI - how to chain user and original RM handler? - ecm, 29.04.2023, 08:43
    • DPMI - how to chain user and original RM handler? - ecm, 29.04.2023, 08:45
      • DPMI - how to chain user and original RM handler? - Laaca, 29.04.2023, 14:04
        • DPMI - how to chain user and original RM handler? - ecm, 29.04.2023, 15:17
  • DPMI - how to chain user and original RM handler? - bretjohn, 04.05.2023, 04:03
  • DPMI - how to chain user and original RM handler? - CandyMan, 05.05.2023, 12:36
    • DPMI - how to chain user and original RM handler? - Laaca, 05.05.2023, 21:53
    • DPMI - how to chain user and original RM handler? - Laaca, 12.06.2023, 23:39