tty.c revision 1.4 
1/*	$NetBSD: tty.c,v 1.4 1994/12/07 00:46:57 jtc Exp $	*/
2
3/*
4 * Copyright (c) 1988, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by the University of
18 *	California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#ifndef lint
37static char copyright[] =
38"@(#) Copyright (c) 1988, 1993\n\
39	The Regents of the University of California.  All rights reserved.\n";
40#endif /* not lint */
41
42#ifndef lint
43#if 0
44static char sccsid[] = "@(#)tty.c	8.1 (Berkeley) 6/6/93";
45#endif
46static char rcsid[] = "$NetBSD: tty.c,v 1.4 1994/12/07 00:46:57 jtc Exp $";
47#endif /* not lint */
48
49#include <stdio.h>
50#include <stdlib.h>
51#include <unistd.h>
52
53static void usage	__P((void));
54
55int
56main(argc, argv)
57	int argc;
58	char **argv;
59{
60	int ch, sflag;
61	char *t;
62
63	sflag = 0;
64	while ((ch = getopt(argc, argv, "s")) != -1) {
65		switch((char)ch) {
66		case 's':
67			sflag = 1;
68			break;
69		case '?':
70		default:
71			usage();
72			/* NOTREACHED */
73		}
74	}
75
76	t = ttyname(STDIN_FILENO);
77	if (!sflag)
78		puts(t ? t : "not a tty");
79	exit(t ? 0 : 1);
80}
81
82
83static void
84usage ()
85{
86	fprintf(stderr, "usage: tty [-s]\n");
87	exit(2);
88}
89