/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*	Copyright (c) 1988 AT&T	*/
/*	  All Rights Reserved  	*/

#pragma ident	"%Z%%M%	%I%	%E% SMI"

#pragma weak _tcgetsid = tcgetsid

#include "lint.h"
#include <sys/termios.h>
#include <sys/types.h>
#include <errno.h>
#include <unistd.h>

pid_t
tcgetsid(int fd)
{
	pid_t ttysid, mysid;

	if ((ioctl(fd, TIOCGSID, &ttysid)) < 0 ||
	    (mysid = getsid(0)) < 0)
		return (-1);
	if (mysid != ttysid) {
		errno = ENOTTY;
		return (-1);
	}
	return (mysid);
}