1/*	$OpenBSD: printenv.c,v 1.8 2015/10/09 01:37:08 deraadt Exp $	*/
2
3/*
4 * Copyright (c) 1987 Regents of the University of California.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <stdio.h>
33#include <string.h>
34#include <stdlib.h>
35#include <unistd.h>
36#include <err.h>
37
38/*
39 * printenv
40 *
41 * Bill Joy, UCB
42 * February, 1979
43 */
44int
45main(int argc, char *argv[])
46{
47	extern char **environ;
48	char *cp, **ep;
49	int len;
50
51	if (pledge("stdio", NULL) == -1)
52		err(1, "pledge");
53
54	if (argc < 2) {
55		for (ep = environ; *ep; ep++)
56			puts(*ep);
57		exit(0);
58	}
59	len = strlen(*++argv);
60	for (ep = environ; *ep; ep++)
61		if (!strncmp(*ep, *argv, len)) {
62			cp = *ep + len;
63			if (!*cp || *cp == '=') {
64				puts(*cp ? cp + 1 : cp);
65				exit(0);
66			}
67		}
68	exit(1);
69}
70