What does ? in C mean?

Question

What does a question mark (?) in C mean?

Answer 1

? is the first symbol of the ?: ternary operator.

a = (b==0) ? 1 : 0;

a will have the value 1 if b is equal to 0, and 0 otherwise.

Answer 2

Its the ternary operator, see http://en.wikipedia.org/wiki/Ternary_operation#C.2C_C.2B.2B.2C_C.23.2C_Objective-C.2C_Java.2C_JavaScript.2C_ActionScript