How would you set a variable to the largest number possible in C?

Question

How would you set a variable to equal infinity (or any guaranteed largest number value) in C?

Answer 1

Normally this is done by 1.0/0.0, but you may get a compile warning on that. I am not aware of other portable ways of doing it in C89, but C99 has macro FP_INFINITE in math.h.

EDIT: Apparently Sam didn't actually want infinity, but integer limits, which can be found in limits.h like others have stated.