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. 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 32 static 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 38 static char sccsid[] = "@(#)hostname.c 8.1 (Berkeley) 5/31/93"; 39 #endif /* not lint */ 40 #endif 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 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 52 static void usage(void) __dead2; 53 54 int 55 main(int argc, char *argv[]) 56 { 57 int ch, sflag, dflag; 58 char *p, hostname[MAXHOSTNAMELEN]; 59 60 sflag = 0; 61 dflag = 0; 62 while ((ch = getopt(argc, argv, "fsd")) != -1) 63 switch (ch) { 64 case 'f': 65 /* 66 * On Linux, "hostname -f" prints FQDN. 67 * BSD "hostname" always prints FQDN by 68 * default, so we accept but ignore -f. 69 */ 70 break; 71 case 's': 72 sflag = 1; 73 break; 74 case 'd': 75 dflag = 1; 76 break; 77 case '?': 78 default: 79 usage(); 80 } 81 argc -= optind; 82 argv += optind; 83 84 if (argc > 1 || (sflag && dflag)) 85 usage(); 86 87 if (*argv) { 88 if (sethostname(*argv, (int)strlen(*argv))) 89 err(1, "sethostname"); 90 } else { 91 if (gethostname(hostname, (int)sizeof(hostname))) 92 err(1, "gethostname"); 93 if (sflag) { 94 p = strchr(hostname, '.'); 95 if (p != NULL) 96 *p = '\0'; 97 } else if (dflag) { 98 p = strchr(hostname, '.'); 99 if (p != NULL) 100 strcpy(hostname, ++p); 101 } 102 (void)printf("%s\n", hostname); 103 } 104 exit(0); 105 } 106 107 static void 108 usage(void) 109 { 110 111 (void)fprintf(stderr, "usage: hostname [-f] [-s | -d] [name-of-host]\n"); 112 exit(1); 113 } 114