#include "apue.h"#include <errno.h>#include <fcntl.h>#include <stropts.h>intptym_open(char *pts_name, int pts_namesz){	char	*ptr;	int		fdm;	/*	 * Return the name of the master device so that on failure	 * the caller can print an error message.  Null terminate	 * to handle case where strlen("/dev/ptmx") > pts_namesz.	 */	strncpy(pts_name, "/dev/ptmx", pts_namesz);	pts_name[pts_namesz - 1] = '\0';	if ((fdm = open(pts_name, O_RDWR)) < 0)		return(-1);	if (grantpt(fdm) < 0) {		/* grant access to slave */		close(fdm);		return(-2);	}	if (unlockpt(fdm) < 0) {	/* clear slave's lock flag */		close(fdm);		return(-3);	}	if ((ptr = ptsname(fdm)) == NULL) {	/* get slave's name */		close(fdm);		return(-4);	}	/*	 * Return name of slave.  Null terminate to handle	 * case where strlen(ptr) > pts_namesz.	 */	strncpy(pts_name, ptr, pts_namesz);	pts_name[pts_namesz - 1] = '\0';	return(fdm);			/* return fd of master */}intptys_open(char *pts_name){	int		fds, setup;	/*	 * The following open should allocate a controlling terminal.	 */	if ((fds = open(pts_name, O_RDWR)) < 0)		return(-5);	/*	 * Check if stream is already set up by autopush facility.	 */	if ((setup = ioctl(fds, I_FIND, "ldterm")) < 0) {		close(fds);		return(-6);	}	if (setup == 0) {		if (ioctl(fds, I_PUSH, "ptem") < 0) {			close(fds);			return(-7);		}		if (ioctl(fds, I_PUSH, "ldterm") < 0) {			close(fds);			return(-8);		}		if (ioctl(fds, I_PUSH, "ttcompat") < 0) {			close(fds);			return(-9);		}	}	return(fds);}