NetBSD/bin/hostname/hostname.c

102 lines
2.9 KiB
C

/* $NetBSD: hostname.c,v 1.21 2014/02/13 12:00:29 elric Exp $ */
/*
* Copyright (c) 1988, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1988, 1993\
The Regents of the University of California. All rights reserved.");
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)hostname.c 8.2 (Berkeley) 4/28/95";
#else
__RCSID("$NetBSD: hostname.c,v 1.21 2014/02/13 12:00:29 elric Exp $");
#endif
#endif /* not lint */
#include <sys/param.h>
#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
__dead static void usage(void);
int
main(int argc, char *argv[])
{
int ch, sflag;
char *p, hostname[MAXHOSTNAMELEN + 1];
setprogname(argv[0]);
sflag = 0;
while ((ch = getopt(argc, argv, "s")) != -1)
switch (ch) {
case 's':
sflag = 1;
break;
case '?':
default:
usage();
}
argc -= optind;
argv += optind;
if (argc > 1)
usage();
if (*argv) {
if (sethostname(*argv, strlen(*argv)))
err(1, "sethostname");
} else {
if (gethostname(hostname, sizeof(hostname)))
err(1, "gethostname");
hostname[sizeof(hostname) - 1] = '\0';
if (sflag && (p = strchr(hostname, '.')))
*p = '\0';
(void)printf("%s\n", hostname);
}
exit(0);
/* NOTREACHED */
}
static void
usage(void)
{
(void)fprintf(stderr, "usage: %s [-s] [name-of-host]\n",
getprogname());
exit(1);
/* NOTREACHED */
}