std::sig_atomic_t

 

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Program termination
abort exit quick_exit (C++11) _Exit (C++11)	atexit at_quick_exit (C++11) EXIT_SUCCESSEXIT_FAILURE
Unreachable control flow
unreachable (C++23)
Communicating with the environment
system	getenv
Signals
signal raise sig_atomic_t	SIG_DFLSIG_IGN SIG_ERR
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SIGABRTSIGFPESIGILL	SIGINTSIGSEGVSIGTERM
Non-local jumps
setjmp	longjmp
Types
jmp_buf

 

Defined in header <csignal>
typedef /* unspecified */ sig_atomic_t;

An integer type which can be accessed as an atomic entity even in the presence of asynchronous interrupts made by signals.

Notes

Until C++11, which introduced std::atomic and std::atomic_signal_fence, about the only thing a strictly conforming program could do in a signal handler was to assign a value to a volatile static std::sig_atomic_t variable and promptly return.

See also

signal	sets a signal handler for particular signal (function)
atomic_signal_fence (C++11)	fence between a thread and a signal handler executed in the same thread (function)
C documentation for sig_atomic_t