xref: /openbsd-src/bin/hostname/hostname.c (revision 080f3bb5642a00c76baf76428cdad45a0059d24f)
1*080f3bb5Sgsoares /*	$OpenBSD: hostname.c,v 1.10 2016/02/01 22:27:25 gsoares Exp $	*/
2df930be7Sderaadt /*	$NetBSD: hostname.c,v 1.10 1995/09/07 06:28:40 jtc Exp $	*/
3df930be7Sderaadt 
4df930be7Sderaadt /*
5df930be7Sderaadt  * Copyright (c) 1988, 1993
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.
1629295d1cSmillert  * 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 
33df930be7Sderaadt #include <err.h>
34df930be7Sderaadt #include <stdio.h>
35df930be7Sderaadt #include <stdlib.h>
36df930be7Sderaadt #include <string.h>
37df930be7Sderaadt #include <unistd.h>
38b9fc9a72Sderaadt #include <limits.h>
39df930be7Sderaadt 
409517852aSmpech extern	char *__progname;
419517852aSmpech 
42*080f3bb5Sgsoares static void __dead usage(void);
43df930be7Sderaadt 
44df930be7Sderaadt int
main(int argc,char * argv[])45ab83b6d6Sderaadt main(int argc, char *argv[])
46df930be7Sderaadt {
47df930be7Sderaadt 	int ch, sflag;
48b9fc9a72Sderaadt 	char *p, hostname[HOST_NAME_MAX+1];
49df930be7Sderaadt 
50df930be7Sderaadt 	sflag = 0;
51df930be7Sderaadt 	while ((ch = getopt(argc, argv, "s")) != -1)
52df930be7Sderaadt 		switch (ch) {
53df930be7Sderaadt 		case 's':
54df930be7Sderaadt 			sflag = 1;
55df930be7Sderaadt 			break;
56df930be7Sderaadt 		default:
57df930be7Sderaadt 			usage();
58df930be7Sderaadt 		}
59df930be7Sderaadt 	argc -= optind;
60df930be7Sderaadt 	argv += optind;
61df930be7Sderaadt 
62df930be7Sderaadt 	if (argc > 1)
63df930be7Sderaadt 		usage();
64df930be7Sderaadt 
65df930be7Sderaadt 	if (*argv) {
66df930be7Sderaadt 		if (sethostname(*argv, strlen(*argv)))
67df930be7Sderaadt 			err(1, "sethostname");
68df930be7Sderaadt 	} else {
69df930be7Sderaadt 		if (gethostname(hostname, sizeof(hostname)))
70df930be7Sderaadt 			err(1, "gethostname");
71df930be7Sderaadt 		if (sflag && (p = strchr(hostname, '.')))
72df930be7Sderaadt 			*p = '\0';
73df930be7Sderaadt 		(void)printf("%s\n", hostname);
74df930be7Sderaadt 	}
75*080f3bb5Sgsoares 	return(0);
76df930be7Sderaadt }
77df930be7Sderaadt 
78*080f3bb5Sgsoares static void __dead
usage(void)79ab83b6d6Sderaadt usage(void)
80df930be7Sderaadt {
819517852aSmpech 	(void)fprintf(stderr, "usage: %s [-s] [name-of-host]\n", __progname);
82df930be7Sderaadt 	exit(1);
83df930be7Sderaadt }
84