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However, this issue was discussed at the April 2008 meeting of ISO/IEC WG14 and it was agreed that there are no known implementations in which it would be an error to read a value to from a volatile static variable and that this was the original intent of the committee and was not properly recordedwas that both reading and writing variables of volatile sig_atomic_t would be strictly conforming.
The signal handler may also call the abort() function, the _Exit(), function, or the signal() function with the first argument equal to the signal number corresponding to the signal that caused the invocation of the handler. This may be necessary to ensure that the handler persists (see SIG01-A. Understand implementation-specific details regarding signal handler persistence).
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