| /* |
| * Copyright (c) 1987, 1993 |
| * The Regents of the University of California. All rights reserved. |
| * (c) UNIX System Laboratories, Inc. |
| * All or some portions of this file are derived from material licensed |
| * to the University of California by American Telephone and Telegraph |
| * Co. or Unix System Laboratories, Inc. and are reproduced herein with |
| * the permission of UNIX System Laboratories, Inc. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * 3. All advertising materials mentioning features or use of this software |
| * must display the following acknowledgement: |
| * This product includes software developed by the University of |
| * California, Berkeley and its contributors. |
| * 4. Neither the name of the University nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * |
| * Modified Fri Mar 10 20:27:19 1995, faith@cs.unc.edu, for Linux |
| * Modified Mon Jul 1 18:14:10 1996, janl@ifi.uio.no, writing to stdout |
| * as suggested by Michael Meskes <meskes@Informatik.RWTH-Aachen.DE> |
| * |
| */ |
| |
| #ifndef lint |
| static char copyright[] = |
| "@(#) Copyright (c) 1987, 1993\n\ |
| The Regents of the University of California. All rights reserved.\n"; |
| #endif /* not lint */ |
| |
| #ifndef lint |
| static char sccsid[] = "@(#)mesg.c 8.2 (Berkeley) 1/21/94"; |
| #endif /* not lint */ |
| |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| |
| #include <err.h> |
| #include <errno.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <unistd.h> |
| |
| int |
| main(argc, argv) |
| int argc; |
| char *argv[]; |
| { |
| struct stat sb; |
| char *tty; |
| int ch; |
| |
| while ((ch = getopt(argc, argv, "")) != EOF) |
| switch (ch) { |
| case '?': |
| default: |
| goto usage; |
| } |
| argc -= optind; |
| argv += optind; |
| |
| if ((tty = ttyname(STDERR_FILENO)) == NULL) |
| err(1, "ttyname"); |
| if (stat(tty, &sb) < 0) |
| err(1, "%s", tty); |
| |
| if (*argv == NULL) { |
| if (sb.st_mode & (S_IWGRP | S_IWOTH)) { |
| (void)fprintf(stdout, "is y\n"); |
| exit(0); |
| } |
| (void)fprintf(stdout, "is n\n"); |
| exit(1); |
| } |
| |
| switch (*argv[0]) { |
| case 'y': |
| #ifdef USE_TTY_GROUP |
| if (chmod(tty, sb.st_mode | S_IWGRP) < 0) |
| err(1, "%s", tty); |
| #else |
| if (chmod(tty, sb.st_mode | S_IWGRP | S_IWOTH) < 0) |
| err(1, "%s", tty); |
| #endif |
| exit(0); |
| case 'n': |
| if (chmod(tty, sb.st_mode & ~(S_IWGRP|S_IWOTH)) < 0) |
| err(1, "%s", tty); |
| exit(1); |
| } |
| |
| usage: (void)fprintf(stderr, "usage: mesg [y | n]\n"); |
| exit(2); |
| } |