STRISTTY
{ SF(STRISTTY), "stream is a terminal" },
if (stp->sd_flag & STRISTTY) {
if (!(stp->sd_flag & STRISTTY) || (flag & FNOCTTY))
stp->sd_flag |= STRISTTY; /* just to be sure */
stp->sd_flag |= STRISTTY;
stp->sd_flag &= ~STRISTTY;
(cmd == I_PUSH) && (stp->sd_flag & STRISTTY)) {
(stp->sd_flag & (STRISTTY|STRXPG4TTY)) == (STRISTTY|STRXPG4TTY)) {