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Signal masks, floating-point status flags, and the state of open files are not saved by the setjmp() function. If signal masks need to be saved, the the sigsetjmp() POSIX function should be used.
This recommendation is related to SIG32-C. Do not call longjmp() from inside a signal handler and ENV32-C. All atexit exit handlers must return normally.
Noncompliant Code Example
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