LA>    Got any ideas ?  What I want is that secret Int call that OS/2
 LA>    will treat as an instruction to take the rest of the slice
 LA>    away...but don't put me so far to sleep that I can't wake up
 LA>    again without keyboard intercession.

It's the DPMI release time slice function:

mov ax, 1680h
int 2fh
cmp al, 80h
jz {at}{at}error

This releases the rest of the time slice under OS/2, Windows and any other
DPMI compliant multitasking operating system.

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