hostname.c revision 1.6 1 /*
2 * Copyright (c) 1988, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #ifndef lint
35 static char copyright[] =
36 "@(#) Copyright (c) 1988, 1993\n\
37 The Regents of the University of California. All rights reserved.\n";
38 #endif /* not lint */
39
40 #ifndef lint
41 /*static char sccsid[] = "from: @(#)hostname.c 8.1 (Berkeley) 5/31/93";*/
42 static char *rcsid = "$Id: hostname.c,v 1.6 1994/09/22 09:25:22 mycroft Exp $";
43 #endif /* not lint */
44
45 #include <sys/param.h>
46
47 #include <err.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <unistd.h>
52
53 void usage __P((void));
54
55 int
56 main(argc,argv)
57 int argc;
58 char *argv[];
59 {
60 int ch, sflag;
61 char *p, hostname[MAXHOSTNAMELEN];
62
63 sflag = 0;
64 while ((ch = getopt(argc, argv, "s")) != -1)
65 switch (ch) {
66 case 's':
67 sflag = 1;
68 break;
69 case '?':
70 default:
71 usage();
72 }
73 argc -= optind;
74 argv += optind;
75
76 if (*argv) {
77 if (sethostname(*argv, strlen(*argv)))
78 err(1, "sethostname");
79 } else {
80 if (gethostname(hostname, sizeof(hostname)))
81 err(1, "gethostname");
82 if (sflag && (p = strchr(hostname, '.')))
83 *p = '\0';
84 (void)printf("%s\n", hostname);
85 }
86 exit(0);
87 }
88
89 void
90 usage()
91 {
92
93 (void)fprintf(stderr, "usage: hostname [-s] [hostname]\n");
94 exit(1);
95 }
96