ptm_fd
if (ptm_fd != -1)
close(ptm_fd);
pid = fdforkpty(ptm_fd, &master, tty, NULL, &ws);
new_wp->pid = fdforkpty(ptm_fd, &new_wp->fd, new_wp->tty, NULL, &ws);
if ((ptm_fd = getptmfd()) == -1)
int ptm_fd = -1;