# getenv

(PHP 4, PHP 5)

getenv — Gets the value of an environment variable

### Description

string getenv ( string `$varname` )

Gets the value of an environment variable.

You can see a list of all the environmental variables by using phpinfo(). You can find out what many of them mean by taking a look at the » CGI specification, specifically the » page on environmental variables.

### Parameters

`varname`

  The variable name.

### Return Values

Returns the value of the environment variable `varname` , or `FALSE` on an error.

### Examples

Example#1 getenv() Example

`<?php
// Example use of getenv()
$ip = getenv('REMOTE_ADDR');
// Or simply use a Superglobal ($_SERVER or $_ENV)
$ip = $_SERVER['REMOTE_ADDR'];
?>`

### See Also

- putenv()
- apache_getenv()
- Superglobals