biff.c revision 24360 
1/*
2 * Copyright (c) 1980, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static char copyright[] =
36"@(#) Copyright (c) 1980, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41static char sccsid[] = "@(#)biff.c	8.1 (Berkeley) 6/6/93";
42#endif /* not lint */
43
44#include <sys/types.h>
45#include <sys/stat.h>
46#include <errno.h>
47#include <unistd.h>
48#include <stdio.h>
49#include <stdlib.h>
50#include <string.h>
51
52static void usage __P((void));
53static void err __P((char *));
54
55main(argc, argv)
56	int argc;
57	char *argv[];
58{
59	struct stat sb;
60	int ch;
61	char *name;
62
63
64	while ((ch = getopt(argc, argv, "")) != -1)
65		switch(ch) {
66		case '?':
67		default:
68			usage();
69		}
70	argc -= optind;
71	argv += optind;
72
73	if ((name = ttyname(STDERR_FILENO)) == NULL) {
74		(void)fprintf(stderr, "biff: unknown tty\n");
75		exit(2);
76	}
77
78	if (stat(name, &sb))
79		err(name);
80
81	if (*argv == NULL) {
82		(void)printf("is %s\n", sb.st_mode&0100 ? "y" : "n");
83		exit(sb.st_mode & 0100 ? 0 : 1);
84	}
85
86	switch(argv[0][0]) {
87	case 'n':
88		if (chmod(name, sb.st_mode & ~0100) < 0)
89			err(name);
90		break;
91	case 'y':
92		if (chmod(name, sb.st_mode | 0100) < 0)
93			err(name);
94		break;
95	default:
96		usage();
97	}
98	exit(sb.st_mode & 0100 ? 0 : 1);
99}
100
101static void
102err(name)
103	char *name;
104{
105	(void)fprintf(stderr, "biff: %s: %s\n", name, strerror(errno));
106	exit(2);
107}
108
109static void
110usage()
111{
112	(void)fprintf(stderr, "usage: biff [y | n]\n");
113	exit(2);
114}
115