1#include <stdlib.h>
2#include <fcntl.h>
3#include <unistd.h>
4#include <pty.h>
5#include <stdio.h>
6#include <pthread.h>
7
8/* Nonstandard, but vastly superior to the standard functions */
9
10int openpty(int *pm, int *ps, char *name, const struct termios *tio, const struct winsize *ws)
11{
12	int m, s, n=0, cs;
13	char buf[20];
14
15	m = open("/dev/ptmx", O_RDWR|O_NOCTTY);
16	if (m < 0) return -1;
17
18	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
19
20	if (ioctl(m, TIOCSPTLCK, &n) || ioctl (m, TIOCGPTN, &n))
21		goto fail;
22
23	if (!name) name = buf;
24	snprintf(name, sizeof buf, "/dev/pts/%d", n);
25	if ((s = open(name, O_RDWR|O_NOCTTY)) < 0)
26		goto fail;
27
28	if (tio) tcsetattr(s, TCSANOW, tio);
29	if (ws) ioctl(s, TIOCSWINSZ, ws);
30
31	*pm = m;
32	*ps = s;
33
34	pthread_setcancelstate(cs, 0);
35	return 0;
36fail:
37	close(m);
38	pthread_setcancelstate(cs, 0);
39	return -1;
40}
41