xref: /freebsd/usr.bin/env/env.c (revision 2546665afcaf0d53dc2c7058fee96354b3680f5a)
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 
34 #ifndef lint
35 static const char copyright[] =
36 "@(#) Copyright (c) 1988, 1993, 1994\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #if 0
41 #ifndef lint
42 static char sccsid[] = "@(#)env.c	8.3 (Berkeley) 4/2/94";
43 #endif /* not lint */
44 #endif
45 
46 #include <sys/cdefs.h>
47 __FBSDID("$FreeBSD$");
48 
49 #include <err.h>
50 #include <errno.h>
51 #include <stdio.h>
52 #include <string.h>
53 #include <stdlib.h>
54 #include <unistd.h>
55 
56 extern char **environ;
57 
58 static void usage(void);
59 
60 int
61 main(int argc, char **argv)
62 {
63 	char **ep, *p;
64 	char *cleanenv[1];
65 	int ch;
66 
67 	while ((ch = getopt(argc, argv, "-i")) != -1)
68 		switch(ch) {
69 		case '-':
70 		case 'i':
71 			environ = cleanenv;
72 			cleanenv[0] = NULL;
73 			break;
74 		case '?':
75 		default:
76 			usage();
77 		}
78 	for (argv += optind; *argv && (p = strchr(*argv, '=')); ++argv)
79 		(void)setenv(*argv, ++p, 1);
80 	if (*argv) {
81 		execvp(*argv, argv);
82 		err(errno == ENOENT ? 127 : 126, "%s", *argv);
83 	}
84 	for (ep = environ; *ep; ep++)
85 		(void)printf("%s\n", *ep);
86 	exit(0);
87 }
88 
89 static void
90 usage(void)
91 {
92 	(void)fprintf(stderr,
93 	    "usage: env [-i] [name=value ...] [utility [argument ...]]\n");
94 	exit(1);
95 }
96