getenv
(PHP 4, PHP 5, PHP 7)
getenv — Gets the value of an environment variable
Description
string getenv ( string $varname [, bool $local_only = false ] )
Gets the value of an environment variable.
You can see a list of all the environmental variables by using phpinfo(). Many of these variables are listed within ? RFC 3875, specifically section 4.1, "Request Meta-Variables".
Parameters
varname
The variable name.
local_only
Set to true to only return local environment variables (set by the operating system or putenv).
Return Values
Returns the value of the environment variable varname
, or FALSE
if the environment variable varname
does not exist.
Changelog
Version | Description |
---|---|
5.5.38, 5.6.24, 7.0.9 | The local_only parameter has been added. |
Notes
Warning
If PHP is running in a SAPI such as Fast CGI, this function will always return the value of an environment variable set by the SAPI, even if putenv() has been used to set a local environment variable of the same name. Use the local_only
parameter to return the value of locally-set environment variables.
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'];
//?Safely?get?the?value?of?an?environment?variable,?ignoring?whether?
//?or?not?it?was?set?by?a?SAPI?or?has?been?changed?with?putenv
$ip?=?getenv('REMOTE_ADDR',?true)??:?getenv('REMOTE_ADDR')
?>
See Also
- putenv() - Sets the value of an environment variable
- apache_getenv() - Get an Apache subprocess_env variable
- Superglobals
← get_resources
getlastmod →
? 1997–2017 The PHP Documentation Group
Licensed under the Creative Commons Attribution License v3.0 or later.
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