another quick n easy question

regarding DO..WHILE.. loops

Code:

---

int variable;

do {
    blah;
    blah;
    blah;
    } while ( variable );

---

the loop executes once at least, and then repeats if the condition specified between the parenthesis is TRUE. i am working with an example that doesn't use an expression, only a integer variable name as the condition. what determines when the variable will evaluate to TRUE and when to FALSE?

Whether or not its value is zero (FALSE) or nonzero (TRUE).

of course..thanks for that