usr/src/bin/hostname/hostname.c

/*
 * Copyright (c) 1988, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * %sccs.include.redist.c%
 */

#ifndef lint
static char copyright[] =
"@(#) Copyright (c) 1988, 1993\n\
        The Regents of the University of California.  All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)hostname.c  8.1 (Berkeley) %G%";
#endif /* not lint */

#include <sys/param.h>

#include <err.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

int
main(argc,argv)
        int argc;
        char *argv[];
{
        extern int optind;
        int ch, sflag;
        char *p, hostname[MAXHOSTNAMELEN];

        sflag = 0;
        while ((ch = getopt(argc, argv, "s")) != EOF)
                switch (ch) {
                case 's':
                        sflag = 1;
                        break;
                case '?':
                default:
                        (void)fprintf(stderr,
                            "usage: hostname [-s] [hostname]\n");
                        exit(1);
                }
        argc -= optind;
        argv += optind;

        if (*argv) {
                if (sethostname(*argv, strlen(*argv)))
                        err(1, "sethostname");
        } else {
                if (gethostname(hostname, sizeof(hostname)))
                        err(1, "gethostname");
                if (sflag && (p = strchr(hostname, '.')))
                        *p = '\0';
                (void)printf("%s\n", hostname);
        }
        exit(0);
}