ifuse_sig_handler
if (old_sa.sa_handler == ifuse_sig_handler)
if (old_sa.sa_handler == ifuse_sig_handler)
if (old_sa.sa_handler == ifuse_sig_handler)
signal(SIGHUP, ifuse_sig_handler);
signal(SIGINT, ifuse_sig_handler);
signal(SIGTERM, ifuse_sig_handler);