signal_handler
act.sa_handler = signal_handler;
static void signal_handler(int signum);
(void) signal(SIGINT, signal_handler);
(void) signal(SIGTERM, signal_handler);
static void signal_handler(int dummy);
(void) signal(SIGINT, signal_handler);
(void) signal(SIGTERM, signal_handler);
static void signal_handler(int);
(void) sigset(SIGHUP, signal_handler);
(void) sigset(SIGTERM, signal_handler);
(void) sigset(SIGINT, signal_handler);
(void) sigset(SIGQUIT, signal_handler);
signal(sig, signal_handler);
act.sa_handler = signal_handler;
if (signal(signals[i], signal_handler) == SIG_IGN) {