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/*
FUNCTION
<<getenv>>---look up environment variable
INDEX
getenv
INDEX
environ
SYNOPSIS
#include <stdlib.h>
char *getenv(const char *<[name]>);
DESCRIPTION
<<getenv>> searches the list of environment variable names and values
(using the global pointer ``<<char **environ>>'') for a variable whose
name matches the string at <[name]>. If a variable name matches,
<<getenv>> returns a pointer to the associated value.
RETURNS
A pointer to the (string) value of the environment variable, or
<<NULL>> if there is no such environment variable.
PORTABILITY
<<getenv>> is ANSI, but the rules for properly forming names of environment
variables vary from one system to another.
<<getenv>> requires a global pointer <<environ>>.
*/
/*
* Copyright (c) 1987, 2000 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that: (1) source distributions retain this entire copyright
* notice and comment, and (2) distributions including binaries display
* the following acknowledgement: ``This product includes software
* developed by the University of California, Berkeley and its contributors''
* in the documentation or other materials provided with the distribution.
* Neither the name of the University nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#define _GNU_SOURCE
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
/*
* getenv --
* Returns ptr to value associated with name, if any, else NULL.
*/
char *
getenv(const char *name)
{
int offset;
return _findenv(name, &offset);
}
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