Hi Lee,

You wrote to David Noon:

LA>LA>    I don't see it that way....what I want to do is relinquish the
LA>LA>    remainder of a slice, when I don't need *all* of it.....that's
LA>LA>    different from saying you have *no* usefull work to do...DV could
LA>LA>    do this, why not OS/2 ?

As I understand it OS/2 does it the same way as DV...



LA>   Dave, I appreciate the advice, but this was concerning a DOS app.
LA>   What I'm looking for is an Int call that OS/2 will interprete as
LA>   a priority downgrade, without totally shutting the application
LA>   off.

I don't know of a way of altering the DOS programs priority from within
the program. I've just looked through Ralf Brown's Interrupt list (I
trust you do have a copy? It's invaluable for this sort of thing!).



LA>   It's a DOS app, not an event-driven specialty OS app...it *has*
LA>   to poll for input at some point.

LA>   My app uses internal multi-tasking to compensate for being
LA>   portable. It knows when it's busy, and when it's wasting
LA>   processor time waiting for a keystroke.

LA>   This is a DOS app, because it's the closest thing there is right
LA>   now to a portable exe format....it'll run under any OS, while
LA>   still taking advantage of specific OS features. Now if I could
LA>   just get the *best* multitasker to treat it as an *intelligent*
LA>   exe, I'll be happy.

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 not secret at all...
Use the standard INT 2F function 1680, from Ralf Brown's interrupt list:

___-----W-2F1680-----------------------------
INT 2F - MS Windows, DPMI, various - RELEASE CURRENT VIRTUAL MACHINE TIME-SLICE
        AX = 1680h
Return: AL = status
            00h if the call is supported
            80h (unchanged) if the call is not supported
Notes:  programs can use this function in idle loops to enhance performance
          under multitaskers; this call is supported by MS Windows 3.0, DOS 5+,
          DPMI 1.0+, and in OS/2 2.0+ for multitasking DOS applications
        does not block the program; it just gives up the remainder of the time
          slice
        should not be used by Windows-specific programs
        when called very often without intermediate screen output under WIN 3+,
          the VM will go into an idle-state and will not receive the next slice
          before 8 seconds. This time can be changed in SYSTEM.INI through
          "IdleVMWakeUpTime=". Setting to zero
results in a long wait.
SeeAlso: INT 15/AX=1000h,INT 15/AX=5305h,INT 21/AH=89h,INT 7A/BX=000Ah

He also documents the OS/2 specific interrupts available in the DOS
box to set the session title and a host of other useful things.

George

 * SLMR 2.1a * Desk: A very large wastebasket with drawers.

--- Maximus/2 3.01