varariable argument functions question (is there a data type for ... ? )

[Charles Lambert <charles.w.lambert@xxxxxxxxx>]

Is there a datatype that represents variable arguments in variable  
argument functions [e.g. int foo(int a, ...); ] ?
If so what is it, and what source file could i find it in?
I'm trying to make bindings to the objective-c runtime for ada on my  
mac os x 10.4 and there is a line in it as such:
typedef id 			(*IMP)(id, SEL, ...);

IMP is used in several structs. Any help with this would be greatly  
appreciated.

Thank you,
Charles Lambert