vmd_sighdlr
void vmd_sighdlr(int sig, short event, void *arg);
signal_set(&ps->ps_evsigint, SIGINT, vmd_sighdlr, ps);
signal_set(&ps->ps_evsigterm, SIGTERM, vmd_sighdlr, ps);
signal_set(&ps->ps_evsighup, SIGHUP, vmd_sighdlr, ps);
signal_set(&ps->ps_evsigpipe, SIGPIPE, vmd_sighdlr, ps);
signal_set(&ps->ps_evsigusr1, SIGUSR1, vmd_sighdlr, ps);