xref: /dragonfly/usr.bin/env/env.c (revision f9a239ec)
1 /*
2  * Copyright (c) 1988, 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) 1988, 1993, 1994 The Regents of the University of California.  All rights reserved.
34  * @(#)env.c	8.3 (Berkeley) 4/2/94
35  * $FreeBSD: src/usr.bin/env/env.c,v 1.5.2.3 2002/06/26 08:23:36 tjr Exp $
36  * $DragonFly: src/usr.bin/env/env.c,v 1.4 2004/12/08 20:17:12 liamfoy Exp $
37  */
38 
39 #include <err.h>
40 #include <errno.h>
41 #include <stdio.h>
42 #include <string.h>
43 #include <stdlib.h>
44 #include <unistd.h>
45 
46 extern char **environ;
47 
48 static void usage(void);
49 
50 int
51 main(int argc, char **argv)
52 {
53 	char **ep, *p;
54 	char *cleanenv[1];
55 	int ch;
56 
57 	while ((ch = getopt(argc, argv, "-i")) != -1)
58 		switch(ch) {
59 		case '-':
60 		case 'i':
61 			environ = cleanenv;
62 			cleanenv[0] = NULL;
63 			break;
64 		default:
65 			usage();
66 		}
67 	for (argv += optind; *argv && (p = strchr(*argv, '=')); ++argv) {
68 		if (setenv(*argv, ++p, 1) == -1)
69 			err(1, "%s", *argv);
70 	}
71 
72 	if (*argv) {
73 		execvp(*argv, argv);
74 		err(errno == ENOENT ? 127 : 126, "%s", *argv);
75 	}
76 	for (ep = environ; *ep; ep++)
77 		printf("%s\n", *ep);
78 	exit(0);
79 }
80 
81 static void
82 usage(void)
83 {
84 	fprintf(stderr,
85 	    "usage: env [-i] [name=value ...] [utility [argument ...]]\n");
86 	exit(1);
87 }
88