SIG_DFL, SIG_IGN

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C++ Standard Library
Language Utilities library Strings library Containers library Algorithms library Iterators library Numerics library Input/output library Localizations library Regular expressions library (C++11) Atomic operations library (C++11) Thread support library (C++11)
Utilities library
Program support utilities
Program termination abort exit quick_exit (C++11) _Exit (C++11) atexit at_quick_exit (C++11) EXIT_SUCCESS EXIT_FAILURE Communicating with the environment system getenv Signals signal raise SIG_DFL SIG_IGN SIG_ERR Signal types SIGABRT SIGFPE SIGILL SIGINT SIGSEGV SIGTERM Non-local jumps setjmp longjmp Types jmp_buf

Defined in header <csignal>
#define SIG_DFL /*implementation defined*/
#define SIG_IGN /*implementation defined*/

The SIG_DFL and SIG_IGN macros expand into integral expressions that are not equal to an address of any function. The macros define signal handling strategies for std::signal() function.

Constant	Explanation
SIG_DFL	default signal handling
SIF_IGN	signal is ignored