usr.bin/logname/logname.c

   1 /*-
   2  * Copyright (c) 1991, 1993, 1994
   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. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * @(#) Copyright (c) 1991, 1993, 1994 The Regents of the University of California.  All rights reserved.
  34  * @(#)logname.c        8.2 (Berkeley) 4/3/94
  35  *
  36  * $DragonFly: src/usr.bin/logname/logname.c,v 1.5 2004/12/13 14:08:44 liamfoy Exp $
  37  */
  38
  39 #include <err.h>
  40 #include <locale.h>
  41 #include <unistd.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44
  45 static void     usage(void);
  46
  47 int
  48 main(int argc, char **argv)
  49 {
  50         int ch;
  51         char *p;
  52
  53         setlocale(LC_ALL, "");
  54
  55         while ((ch = getopt(argc, argv, "")) != -1)
  56                 switch (ch) {
  57                 case '?':
  58                 default:
  59                         usage();
  60                 }
  61         argc -= optind;
  62         argv += optind;
  63
  64         if ((p = getlogin()) == NULL)
  65                 err(1, "getlogin failed");
  66         printf("%s\n", p);
  67         exit(0);
  68 }
  69
  70 static void
  71 usage(void)
  72 {
  73         fprintf(stderr, "usage: logname\n");
  74         exit(1);
  75 }