1 /* $OpenBSD: logname.c,v 1.7 2009/10/27 23:59:40 deraadt Exp $ */ 2 /* $NetBSD: logname.c,v 1.6 1994/12/22 06:39:32 jtc Exp $ */ 3 4 /*- 5 * Copyright (c) 1991, 1993, 1994 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 <stdio.h> 34 #include <stdlib.h> 35 #include <locale.h> 36 #include <unistd.h> 37 #include <err.h> 38 39 void usage(void); 40 41 int 42 main(int argc, char *argv[]) 43 { 44 int ch; 45 char *p; 46 47 setlocale(LC_ALL, ""); 48 49 while ((ch = getopt(argc, argv, "")) != -1) 50 switch (ch) { 51 case '?': 52 default: 53 usage(); 54 /* NOTREACHED */ 55 } 56 57 if (argc != optind) { 58 usage(); 59 /* NOTREACHED */ 60 } 61 62 if ((p = getlogin()) == NULL) 63 err(1, NULL); 64 (void)printf("%s\n", p); 65 exit(0); 66 } 67 68 void 69 usage(void) 70 { 71 (void)fprintf(stderr, "usage: logname\n"); 72 exit(1); 73 } 74