1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
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. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #ifndef lint
33 static const char copyright[] =
34 "@(#) Copyright (c) 1988, 1993\n\
35 The Regents of the University of California. All rights reserved.\n";
36 #endif /* not lint */
37
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)tty.c 8.1 (Berkeley) 6/6/93";
41 #endif
42 #endif /* not lint */
43
44 #include <sys/cdefs.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <unistd.h>
48
49 static void usage(void) __dead2;
50
51 int
main(int argc,char * argv[])52 main(int argc, char *argv[])
53 {
54 int ch, sflag;
55 char *t;
56
57 sflag = 0;
58 while ((ch = getopt(argc, argv, "s")) != -1)
59 switch (ch) {
60 case 's':
61 sflag = 1;
62 break;
63 case '?':
64 default:
65 usage();
66 /* NOTREACHED */
67 }
68
69 t = ttyname(STDIN_FILENO);
70 if (!sflag)
71 puts(t ? t : "not a tty");
72 exit(t ? EXIT_SUCCESS : EXIT_FAILURE);
73 }
74
75 static void
usage(void)76 usage(void)
77 {
78 fprintf(stderr, "usage: %s [-s]\n", getprogname());
79 exit(2);
80 }
81