Class sigaction

zic.c:1115–1115

    struct sigaction act0, act;
    act.sa_handler = signal_handler;
    sigemptyset(&act.sa_mask);
    act.sa_flags = 0;
    if (sigaction(signals[i], &act, &act0) == 0
	&& ! (act0.sa_flags & SA_SIGINFO) && act0.sa_handler == SIG_IGN) {