SIG_DFL, SIG_IGN - cppreference.com

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SIG_DFLSIG_IGN
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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
`SIG_IGN`	signal is ignored

See also