2 * Copyright (c) 1987, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 static const char copyright[] =
37 "@(#) Copyright (c) 1987, 1993\n\
38 The Regents of the University of California. All rights reserved.\n";
43 static char sccsid[] = "@(#)mesg.c 8.2 (Berkeley) 1/21/94";
46 #include <sys/cdefs.h>
47 __FBSDID("$FreeBSD$");
49 #include <sys/types.h>
58 static void usage(void);
61 main(int argc, char *argv[])
67 while ((ch = getopt(argc, argv, "")) != -1)
76 if ((tty = ttyname(STDIN_FILENO)) == NULL &&
77 (tty = ttyname(STDOUT_FILENO)) == NULL &&
78 (tty = ttyname(STDERR_FILENO)) == NULL)
80 if (stat(tty, &sb) < 0)
84 if (sb.st_mode & S_IWGRP) {
94 if (chmod(tty, sb.st_mode | S_IWGRP) < 0)
98 if (chmod(tty, sb.st_mode & ~S_IWGRP) < 0)
110 (void)fprintf(stderr, "usage: mesg [n | y]\n");