1 /*-
2 * Copyright (c) 1991 The Regents of the University of California.
3 * 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
34 #ifndef lint
35 char copyright[] =
36 "@(#) Copyright (c) 1991 The Regents of the University of California.\n\
37 All rights reserved.\n";
38 #endif /* not lint */
39
40 #ifndef lint
41 static char sccsid[] = "@(#)logname.c 5.1 (Berkeley) 6/28/91";
42 #endif /* not lint */
43
44 #include <errno.h>
45 #include <unistd.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49
main(argc,argv)50 main(argc, argv)
51 int argc;
52 char *argv[];
53 {
54 int ch;
55 char *p;
56
57 while ((ch = getopt(argc, argv, "")) != EOF)
58 switch(ch) {
59 case '?':
60 default:
61 usage();
62 }
63 argc -= optind;
64 argv += optind;
65
66 if ((p = getlogin()) == NULL) {
67 (void)fprintf(stderr, "logname: %s\n", strerror(errno));
68 exit(1);
69 }
70 (void)printf("%s\n", p);
71 exit(0);
72 }
73
usage()74 usage()
75 {
76 (void)fprintf(stderr, "usage: logname\n");
77 exit(1);
78 }
79