> it's IMPORTANT that the registers aren't changed before/after
 > the call.
Even flags registers?
 > It's not so much of an override, but rather a way around a
 > particular
 > problem. Since DOS isn't re-entrant, you can't call DOS when
 Yeah. there the problem.
 > INT 21h:      <-            <----
 >   mov  AH,09h                   |
 >   mov  DX,offset message        |   goes into infinate loop?
 >   int  21h                   ---|
I'm not calling int 21h inside another int 21h. i know it could has a side
effect like this. :-)
But say calling int 21h from int 2dh
 > Firstly reserve
 > some space for the stack in your program.
 When i use int 21h/31 must i include the stack area too? or round up to
 executable code only.
 > Upon exiting your TSR program, just reverse the process to
 > switch the
 > stacks back.
Easy to demonstrate how things works but actually get it done its another
pair of hands.
Thanks!
Sylvain
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