/*
- * Copyright (c) 1987 Regents of the University of California.
- * All rights reserved.
+ * 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 are permitted
- * provided that this notice is preserved and that due credit is given
- * to the University of California at Berkeley. The name of the University
- * may not be used to endorse or promote products derived from this
- * software without specific written prior permission. This software
- * is provided ``as is'' without express or implied warranty.
+ * 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.
*/
#ifndef lint
-char copyright[] =
-"@(#) Copyright (c) 1987 Regents of the University of California.\n\
- All rights reserved.\n";
+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 4.4 (Berkeley) %G%";
+static char sccsid[] = "@(#)mesg.c 8.2 (Berkeley) 1/21/94";
#endif /* not lint */
-/*
- * mesg -- set current tty to accept or
- * forbid write permission.
- *
- * mesg [y] [n]
- * y allow messages
- * n forbid messages
- */
-
#include <sys/types.h>
#include <sys/stat.h>
-#include <stdio.h>
-static char *tty;
+#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;
+ char *argv[];
{
- struct stat sbuf;
- char *ttyname();
+ struct stat sb;
+ char *tty;
+ int ch;
- if (!(tty = ttyname(2))) {
- fputs("mesg: not a device in /dev.\n", stderr);
- exit(-1);
- }
- if (stat(tty, &sbuf) < 0) {
- perror("mesg");
- exit(-1);
- }
- if (argc < 2) {
- if (sbuf.st_mode & 020) {
- fputs("is y\n", stderr);
+ 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) {
+ (void)fprintf(stderr, "is y\n");
exit(0);
}
- fputs("is n\n", stderr);
+ (void)fprintf(stderr, "is n\n");
exit(1);
}
-#define OTHER_WRITE 020
- switch(*argv[1]) {
+
+ switch (*argv[0]) {
case 'y':
- newmode(sbuf.st_mode | OTHER_WRITE);
+ if (chmod(tty, sb.st_mode | S_IWGRP) < 0)
+ err(1, "%s", tty);
exit(0);
case 'n':
- newmode(sbuf.st_mode &~ OTHER_WRITE);
+ if (chmod(tty, sb.st_mode & ~S_IWGRP) < 0)
+ err(1, "%s", tty);
exit(1);
- default:
- fputs("usage: mesg [y] [n]\n", stderr);
- exit(-1);
}
- /*NOTREACHED*/
-}
-static
-newmode(m)
- u_short m;
-{
- if (chmod(tty, m) < 0) {
- perror("mesg");
- exit(-1);
- }
+usage: (void)fprintf(stderr, "usage: mesg [y | n]\n");
+ exit(2);
}