hostname.c revision 165004
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 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30#if 0 31#ifndef lint 32static char const copyright[] = 33"@(#) Copyright (c) 1988, 1993\n\ 34 The Regents of the University of California. All rights reserved.\n"; 35#endif /* not lint */ 36 37#ifndef lint 38static char sccsid[] = "@(#)hostname.c 8.1 (Berkeley) 5/31/93"; 39#endif /* not lint */ 40#endif 41#include <sys/cdefs.h> 42__FBSDID("$FreeBSD: head/bin/hostname/hostname.c 165004 2006-12-08 07:19:51Z kientzle $"); 43 44#include <sys/param.h> 45 46#include <err.h> 47#include <stdio.h> 48#include <stdlib.h> 49#include <string.h> 50#include <unistd.h> 51 52void usage(void); 53 54int 55main(int argc, char *argv[]) 56{ 57 int ch, sflag; 58 char *p, hostname[MAXHOSTNAMELEN]; 59 60 sflag = 0; 61 while ((ch = getopt(argc, argv, "sf")) != -1) 62 switch (ch) { 63 case 'f': 64 /* On Linux, "hostname -f" prints FQDN. */ 65 /* BSD "hostname" always print FQDN by 66 * default, so we accept but ignore -f. */ 67 break; 68 case 's': 69 sflag = 1; 70 break; 71 case '?': 72 default: 73 usage(); 74 } 75 argc -= optind; 76 argv += optind; 77 78 if (argc > 1) 79 usage(); 80 81 if (*argv) { 82 if (sethostname(*argv, (int)strlen(*argv))) 83 err(1, "sethostname"); 84 } else { 85 if (gethostname(hostname, (int)sizeof(hostname))) 86 err(1, "gethostname"); 87 if (sflag) { 88 p = strchr(hostname, '.'); 89 if (p != NULL) 90 *p = '\0'; 91 } 92 (void)printf("%s\n", hostname); 93 } 94 exit(0); 95} 96 97void 98usage(void) 99{ 100 101 (void)fprintf(stderr, "usage: hostname [-s] [name-of-host]\n"); 102 exit(1); 103} 104