github.com/afumu/libc@v0.0.6/musl/src/misc/openpty.c (about)

     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  
    10  int 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;
    36  fail:
    37  	close(m);
    38  	pthread_setcancelstate(cs, 0);
    39  	return -1;
    40  }