handle_signal
handle_signal(&act, sig, info, ucp);
handle_signal(&act, info.si_signo, &info, uc);
static void handle_signal(struct sigaction *, int, siginfo_t *, ucontext_t *);
sighandler_t original = signal(SIGUSR1, handle_signal);
sighandler_t original = signal(SIGCHLD, handle_signal);
sighandler_t original = signal(SIGCHLD, handle_signal);
signal(SIGUSR1, handle_signal);
sighandler_t original = signal(SIGCHLD, handle_signal);
sighandler_t original = signal(SIGCHLD, handle_signal);
signal(SIGINT, handle_signal);
signal(SIGCHLD, handle_signal);
void handle_signal(int);
signal(SIGINT, handle_signal);