🚀 go-pugleaf

Greetings!

I'm about to redirect some interrupts into some code I'm hooking
onto Int 8 or 1C.  When I comes down to calling the 'savedintvector'
I'd like to call it safely.  Can I just call it or should I call it
through the _chain_int function?

I'm also using _dos_setvect and _dos_getvect which use the Int 21 interface
but I'm still don't understand where a new stack is created for the
interrupt routine.  Since DOS is not reentrant, I know its stack has to be
left alone while the interrupt uses its own stack.  Does _dos_setvect
and _dos_getvect take care of creating and deleting a new stack for me?

The reason I'm wondering whether to use _chain_int or not is because I'm
not sure exactly what it does.  I just don't want to risk clobbering the
DOS stack (which probably isn't very big) if my interrupt routine starts
using the stack heavily.  I don't intend to call any DOS routines in my
interrupt.

BTW. What the heck does the keyword 'interrupt' mean in MSC 5.1?  I can't
     find it described anywhere.  Does this somehow take care of keeping
     the DOS stack in order for me?

Any info or pointers to good literature/PD code would be appreciated.

Regards,
Cliff Yamamoto
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Email:  cyamamot@kilroy.jpl.nasa.gov    |     cyamamot@grissom.jpl.nasa.gov
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        cky@hydra.jpl.nasa.gov          |     
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