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(1) Functions return 0 if false, and non-zero if true [1].
(2) Function failures can typically be indicated by one of the following return values: -1, or: any non-zero number.
(3) Comparison functions return 0 if the arguments are equal and non-zero otherwise. (such as the standard library function strcmp() which has a trinary return value [12]) return 0 if the arguments are equal and non-zero otherwise.
Noncompliant Code Example
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