SHUT_RD
shutdown(3, SHUT_RD);
#ifndef SHUT_RD
what = SHUT_RD;
case SHUT_RD:
if ((how < SHUT_RD) || (how > SHUT_RDWR))
case SHUT_RD:
if (mode < SHUT_RD || mode > SHUT_RDWR)
if (shutdown(fd, SHUT_RD)) {