MR> Summary: I want to write a resident program, which will run under DOS
 MR> task in OS/2, and when I press Ctrl-Alt-Del, it will call my own
 MR> procedure. That's all...

That's not possible for two reasons:
1) All interrupts & IRQs occurring in v86 mode (DOS box) will be
vectored to the system.
2) The system keyboard driver intercepts C-A-D and will not reflect it back
to the v86 task.

It is possible to write an OS/2 device driver that will intercept C-A-D
globally, but that's probably not what you're after.

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