Externals?

[chemicalNova]

Howdy all,

I was wondering if it is possible to declare an external type, and an external function? What I'm wanting to do is hook Counter-Strike: Source and write my own MOD for it (I'm just learning at the moment, but I think I could make some sort of FunMOD for it). I've had experience in C++ doing this before, just not in MASM. How would I go about declaring an external type to use in my procedures? (Something like, "extern Type ?")

Ta in advance,

chem