#include <signal.h> int raise(int sig);
The raise() function sends the signal sig to the executing thread. If a signal handler is called, the raise function does not return until after the signal handler returns.
The effect of the raise function is equivalent to calling:
Upon successful completion, 0 is returned. Otherwise, −1 is returned and errno is set to indicate the error.
See attributes(5) for descriptions of the following attributes: