SL> But say about a program once activated (hot-key) is waiting for some 
ther
SL> keys in a menu. The background program in this task should die (pause) 
until
SL> the activated program gives back the control to the keyboard interrupt.
SL> It is the way that most of programs work?
Ok, yes, since the activated TSR program would now act like the primary
function. It would be as if you ran the program in the first place. If it
relies on key presses, then it would wait and sit for you to press a key.
SL> Or the background program should not die because the activated program
SL> gives back the control to the keyboard interrupt and waiting for some 
ore
SL> input. Leaving the background program running correctly.
You could do that do, depending on the need and complexity of the program. A
simple: check key do this and return program could work like so.
For example I wrote a program which uses the Win'95 keys in DOS to toggle
between a color or gray palette. (gray is nice for night time) The program's
a simple TSR that hooks into the keyboard interrupt.
When a key is pressed, the keyboard interrupt is envoked. Somwhere down the
line, by program would check for it's hot keys. If the key is detected to
turn the palette gray, then this code is executed. Upon completion of 
hanging
the palette, the program exits frm the handler as normal. I this case the
foreground program would be interrupted for a brief moment.
SL> In that case, the screen would have been overwritten by the background 
task?
Ahh, true, this would make sense. Since if the TSR wasn't in control 100%
you might see the download bar or something.
SL> I could said wrong. I am just thinking.
I suppose it depends on what sort of TSR your developing that would determine
it's interaction with the system. A simple one like my palette changer for
example allows things to continue on. However a more complicated one like a
popup TSR program would probably stop things.
Cheers,
  Denis Boyles
 * OLX 2.1 TD * Richards Simmons Borg: Assimulating to the oldies
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