xref: /netbsd-src/usr.bin/env/env.c (revision cda4f8f6ee55684e8d311b86c99ea59191e6b74f)
1 /*
2  * Copyright (c) 1988 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) 1988 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[] = "@(#)env.c	5.3 (Berkeley) 6/1/90";
42 #endif /* not lint */
43 
44 #include <stdio.h>
45 #include <string.h>
46 #include <errno.h>
47 
48 static void usage();
49 
50 main(argc, argv)
51 	int argc;
52 	char **argv;
53 {
54 	extern char **environ;
55 	extern int errno, optind;
56 	register char **ep, *p;
57 	char *cleanenv[1];
58 	int ch;
59 
60 	while ((ch = getopt(argc, argv, "-i")) != EOF)
61 		switch((char)ch) {
62 		case '-':			/* obsolete */
63 		case 'i':
64 			environ = cleanenv;
65 			cleanenv[0] = NULL;
66 			break;
67 		case '?':
68 		default:
69 			usage();
70 		}
71 
72 	for (argv += optind; *argv && (p = index(*argv, '=')); ++argv)
73 		(void)setenv(*argv, ++p, 1);
74 
75 	if (*argv) {
76 		/* return 127 if the command to be run could not be found; 126
77 		   if the command was was found but could not be invoked */
78 		int status;
79 
80 		execvp(*argv, argv);
81 		status = (errno == ENOENT) ? 127 : 126;
82 		(void)fprintf(stderr, "env: %s: %s\n", *argv, strerror(errno));
83 		exit(status);
84 	}
85 
86 	for (ep = environ; *ep; ep++)
87 		(void)printf("%s\n", *ep);
88 
89 	exit(0);
90 }
91 
92 static void
93 usage ()
94 {
95 	(void) fprintf(stderr, "usage: env [-i] [name=value ...] [command]\n");
96 	exit (1);
97 }
98