Re: Installing a C function into the IDT

The Prisoner wrote:
> Hey-
> 
> I was reading about interrupts, and I got to thinking it would be a real

> neat thing to use interrupts for program-wide exception handling. What I

> haven't been able to find is a clear guide or example program for how to

> install a C function into the IDT. And what happens about passing 
> arguments?
> 
> I'd like to have something like this:
> 
> void malloc_failure();
> 
> Say I install this as interrupt slot 42, then I can do:
> 
> if(!(p=(int*)malloc(1000*4))) // array of 1000 ints
>   __asm__ ("int $0x42");
> 
> Is there any reason for this not to work? How do I set up the 
> interrupts? Would I need root privelidges to do that?
> 
> Thanks!!

This would be interrupt based exception handling... a risky business.

It would be difficult to write it in C. Normally interrupt servicing
routines should return with a return from interrupt instruction, and not
just a return like a normal function does. You compiler would need
to sup****t that...

Besides, interrupt routines should not destroy any registers, and the
registers it uses should have been saved...

Etc. There many problems with this approach.



-- 
jacob navia
jacob at jacob point remcomp point fr
logiciels/informatique
http://www.cs.virginia.edu/~lcc-win32