xref: /openbsd-src/usr.bin/logname/logname.c (revision 540553b1a5d1f91568c68937f4d6f3fbe2314661)
1*540553b1Sschwarze /*	$OpenBSD: logname.c,v 1.10 2016/10/13 11:51:02 schwarze Exp $	*/
2df930be7Sderaadt /*	$NetBSD: logname.c,v 1.6 1994/12/22 06:39:32 jtc Exp $	*/
3df930be7Sderaadt 
4df930be7Sderaadt /*-
5df930be7Sderaadt  * Copyright (c) 1991, 1993, 1994
6df930be7Sderaadt  *	The Regents of the University of California.  All rights reserved.
7df930be7Sderaadt  *
8df930be7Sderaadt  * Redistribution and use in source and binary forms, with or without
9df930be7Sderaadt  * modification, are permitted provided that the following conditions
10df930be7Sderaadt  * are met:
11df930be7Sderaadt  * 1. Redistributions of source code must retain the above copyright
12df930be7Sderaadt  *    notice, this list of conditions and the following disclaimer.
13df930be7Sderaadt  * 2. Redistributions in binary form must reproduce the above copyright
14df930be7Sderaadt  *    notice, this list of conditions and the following disclaimer in the
15df930be7Sderaadt  *    documentation and/or other materials provided with the distribution.
16f75387cbSmillert  * 3. Neither the name of the University nor the names of its contributors
17df930be7Sderaadt  *    may be used to endorse or promote products derived from this software
18df930be7Sderaadt  *    without specific prior written permission.
19df930be7Sderaadt  *
20df930be7Sderaadt  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21df930be7Sderaadt  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22df930be7Sderaadt  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23df930be7Sderaadt  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24df930be7Sderaadt  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25df930be7Sderaadt  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26df930be7Sderaadt  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27df930be7Sderaadt  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28df930be7Sderaadt  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29df930be7Sderaadt  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30df930be7Sderaadt  * SUCH DAMAGE.
31df930be7Sderaadt  */
32df930be7Sderaadt 
33*540553b1Sschwarze #include <err.h>
34df930be7Sderaadt #include <stdio.h>
35df930be7Sderaadt #include <stdlib.h>
36df930be7Sderaadt #include <unistd.h>
37df930be7Sderaadt 
38*540553b1Sschwarze static void __dead
usage(void)39*540553b1Sschwarze usage(void)
40*540553b1Sschwarze {
41*540553b1Sschwarze 	(void)fprintf(stderr, "usage: logname\n");
42*540553b1Sschwarze 	exit(1);
43*540553b1Sschwarze }
44df930be7Sderaadt 
45df930be7Sderaadt int
main(int argc,char * argv[])461837a5caSderaadt main(int argc, char *argv[])
47df930be7Sderaadt {
48df930be7Sderaadt 	int ch;
49df930be7Sderaadt 	char *p;
50df930be7Sderaadt 
510bd1216cSderaadt 	if (pledge("stdio", NULL) == -1)
520bd1216cSderaadt 		err(1, "pledge");
53bf0edf09Sderaadt 
5472799b18Smillert 	while ((ch = getopt(argc, argv, "")) != -1)
55df930be7Sderaadt 		switch (ch) {
56df930be7Sderaadt 		default:
57df930be7Sderaadt 			usage();
58df930be7Sderaadt 		}
59df930be7Sderaadt 
60*540553b1Sschwarze 	if (argc != optind)
61df930be7Sderaadt 		usage();
62df930be7Sderaadt 
63df930be7Sderaadt 	if ((p = getlogin()) == NULL)
64df930be7Sderaadt 		err(1, NULL);
65df930be7Sderaadt 
66*540553b1Sschwarze 	(void)printf("%s\n", p);
67*540553b1Sschwarze 	return 0;
68df930be7Sderaadt }
69