SIG_ERR

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Program support utilities
Program termination
(C++11)
(C++11)
Communicating with the environment
Signals
SIG_ERR
Signal types
Non-local jumps
Types
Defined in header <csignal>
#define SIG_ERR /* implementation defined */

A value of type void (*)(int). When returned by std::signal, indicates that an error has occurred.

See also

sets a signal handler for particular signal
(function)