XCLUDE
cntrl.c_cflag &= ~XCLUDE;
buf.c_cflag &= ~XCLUDE;
t.c_cflag |= XCLUDE|HUPCL;
if ((tp->t_new_lflags & XCLUDE) &&
tp->t_new_lflags |= XCLUDE;
tp->t_new_lflags &= ~XCLUDE;