1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22/*
23 * Copyright (c) 1996, by Sun Microsystems, Inc.
24 * All rights reserved.
25 */
26
27#pragma ident	"%Z%%M%	%I%	%E% SMI"
28
29/*
30 * MKS interface extension.
31 * A version of getenv() that doesn't overwrite it's return value
32 * on each call.
33 *
34 * Copyright 1995 by Mortice Kern Systems Inc.  All rights reserved.
35 *
36 */
37
38#ifdef M_RCSID
39#ifndef lint
40static char const rcsID[] = "$Header: /rd/src/libc/mks/rcs/m_getenv.c 1.2 1995/07/11 16:53:01 ross Exp $";
41#endif /*lint*/
42#endif /*M_RCSID*/
43
44#include <mks.h>
45#include <stdlib.h>
46#include <string.h>
47
48#ifdef M_NON_STATIC_GETENV
49
50#undef __m_getenv
51
52/*f
53 *  Assume getenv() works the way we expect it to on PC systems.
54 */
55char *
56__m_getenv(char const *name) {
57	return getenv(name);
58}
59
60#else /* M_NON_STATIC_GETENV */
61
62extern char **environ;
63
64/*f
65 *  A version of getenv safe to use in library functions.  According to
66 *  ANSI C and XPG 4 no library function shall behave as if it called
67 *  getenv.  This is a problem on systems that have getenv functions
68 *  that overwrite their return value on each call.
69 */
70
71char *
72__m_getenv(char const *name) {
73	if (m_setenv() != NULL) {
74		int len = strlen(name);
75		char **envp = environ;
76		char *s = *envp++;
77
78		while(s != NULL) {
79			if (strncmp(name, s, len) == 0 && s[len] == '=') {
80				return s + len + 1;
81			}
82			s = *envp++;
83		}
84	}
85	return NULL;
86}
87
88#endif /* M_NON_STATIC_GETENV */
89