logname.c revision 1.5 
1/*	$NetBSD: logname.c,v 1.5 1994/12/22 06:33:42 jtc Exp $	*/
2
3/*-
4 * Copyright (c) 1991, 1993, 1994
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) 1991, 1993, 1994\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[] = "@(#)logname.c	8.2 (Berkeley) 4/3/94";
45#endif
46static char rcsid[] = "$NetBSD: logname.c,v 1.5 1994/12/22 06:33:42 jtc Exp $";
47#endif /* not lint */
48
49#include <stdio.h>
50#include <stdlib.h>
51#include <unistd.h>
52#include <err.h>
53
54void usage __P((void));
55
56int
57main(argc, argv)
58	int argc;
59	char *argv[];
60{
61	int ch;
62	char *p;
63
64	while ((ch = getopt(argc, argv, "")) != EOF)
65		switch (ch) {
66		case '?':
67		default:
68			usage();
69		}
70	argc -= optind;
71	argv += optind;
72
73	if ((p = getlogin()) == NULL)
74		err(1, NULL);
75	(void)printf("%s\n", p);
76	exit(0);
77}
78
79void
80usage()
81{
82	(void)fprintf(stderr, "usage: logname\n");
83	exit(1);
84}
85