xref: /freebsd/bin/pwd/pwd.c (revision 6990ffd8a95caaba6858ad44ff1b3157d1efba8f)
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 
34 #ifndef lint
35 static char const copyright[] =
36 "@(#) Copyright (c) 1991, 1993, 1994\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 #if 0
42 static char sccsid[] = "@(#)pwd.c	8.3 (Berkeley) 4/1/94";
43 #endif
44 static const char rcsid[] =
45   "$FreeBSD$";
46 #endif /* not lint */
47 
48 #include <err.h>
49 #include <limits.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <unistd.h>
53 #include <sys/param.h>
54 
55 int main __P((int, char *[]));
56 void usage __P((void));
57 
58 int
59 main(argc, argv)
60 	int argc;
61 	char *argv[];
62 {
63 	int ch;
64 	char *p;
65 	char buf[PATH_MAX];
66 
67 	/*
68 	 * Flags for pwd are a bit strange.  The POSIX 1003.2B/D9 document
69 	 * has an optional -P flag for physical, which is what this program
70 	 * will produce by default.  The logical flag, -L, should fail, as
71 	 * there's no way to display a logical path after forking.
72 	 */
73 	while ((ch = getopt(argc, argv, "P")) != -1)
74 		switch (ch) {
75 		case 'P':
76 			break;
77 		case '?':
78 		default:
79 			usage();
80 		}
81 	argc -= optind;
82 	argv += optind;
83 
84 	if (argc == 1) {
85 		p = realpath(argv[0], buf);
86 		if (p == NULL)
87 			err(1, "%s", argv[0]);
88 		(void)printf("%s\n", p);
89 	} else  if (argc == 0) {
90 		p = getcwd(NULL, (size_t)0);
91 		if (p == NULL)
92 			err(1, ".");
93 		(void)printf("%s\n", p);
94 	} else {
95 		usage();
96 	}
97 
98 	exit(0);
99 }
100 
101 void
102 usage()
103 {
104 
105 	(void)fprintf(stderr, "usage: pwd\n");
106 	exit(1);
107 }
108