1 /* $OpenBSD: hostname.c,v 1.10 2016/02/01 22:27:25 gsoares Exp $ */ 2 /* $NetBSD: hostname.c,v 1.10 1995/09/07 06:28:40 jtc Exp $ */ 3 4 /* 5 * Copyright (c) 1988, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33 #include <err.h> 34 #include <stdio.h> 35 #include <stdlib.h> 36 #include <string.h> 37 #include <unistd.h> 38 #include <limits.h> 39 40 extern char *__progname; 41 42 static void __dead usage(void); 43 44 int 45 main(int argc, char *argv[]) 46 { 47 int ch, sflag; 48 char *p, hostname[HOST_NAME_MAX+1]; 49 50 sflag = 0; 51 while ((ch = getopt(argc, argv, "s")) != -1) 52 switch (ch) { 53 case 's': 54 sflag = 1; 55 break; 56 default: 57 usage(); 58 } 59 argc -= optind; 60 argv += optind; 61 62 if (argc > 1) 63 usage(); 64 65 if (*argv) { 66 if (sethostname(*argv, strlen(*argv))) 67 err(1, "sethostname"); 68 } else { 69 if (gethostname(hostname, sizeof(hostname))) 70 err(1, "gethostname"); 71 if (sflag && (p = strchr(hostname, '.'))) 72 *p = '\0'; 73 (void)printf("%s\n", hostname); 74 } 75 return(0); 76 } 77 78 static void __dead 79 usage(void) 80 { 81 (void)fprintf(stderr, "usage: %s [-s] [name-of-host]\n", __progname); 82 exit(1); 83 } 84