Installing a C function into the IDT

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!!