S_HANGUP
if (arg & ~(S_INPUT|S_HIPRI|S_OUTPUT|S_MSG|S_ERROR|S_HANGUP))
if (arg & S_HANGUP)
if (ioctl(PCpipe[1], I_SETSIG, S_HANGUP) == -1) {
#define ALLSIG (S_INPUT|S_HIPRI|S_OUTPUT|S_MSG|S_ERROR|S_HANGUP|S_RDNORM|\
if (arg & ~(S_INPUT|S_HIPRI|S_MSG|S_HANGUP|S_ERROR|
~(S_INPUT|S_HIPRI|S_MSG|S_HANGUP|S_ERROR|
if (stp->sd_sigflags & S_HANGUP)
strsendsig(stp->sd_siglist, S_HANGUP, 0, 0);
if (sevent & S_HANGUP) {
sevent &= ~S_HANGUP;