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EXP12-C-EX1: If the return value is inconsequential or if any errors can be safely ignored, such as for functions called because of their side effects, the function should be explicitly cast to void to signify programmer intent. For an example of this exception, see "Compliant Solution (Remove Existing Destination File)" under the section "Portable Behavior" in FIO10-C. Take care when using the rename() function, or Exception ERR33-C-EX1 in ERR33-C. Detect and handle standard library errors.
EXP12-C-EX2: If a function cannot fail or if the return value cannot signify an error condition, the return value may be ignored. Such functions should be added to a whitelist when automatic checkers are used.
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