gtty
gtty(0, &tty);
if (gtty(fileno(stdin), &ttybuf) < 0) {
#define GTTY(fd, mode) gtty(fd, mode)
if (gtty(0, &ttys[0]) >= 0)
if (gtty(1, &ttys[1]) >= 0)
#define savetty() ((void) gtty(_tty_ch, &_tty), _res_flg = _tty.sg_flags)
extern int gtty(int, struct sgttyb *);
if (gtty(_tty_ch, &_tty) < 0)
/* 32 */ SYSENT_CI("gtty", gtty, 2),
/* 32 */ SYSENT_CI("gtty", gtty, 2),
int gtty(int, intptr_t);