getenv
(PHP 4, PHP 5)
getenv — Gets the value of an environment variable
说明
string getenv ( string $varname )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".
参数
- varname
-
The variable name.
返回值
Returns the value of the environment variable varname, or FALSE if the environment variable varname does not exist.
范例
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'];
?>
参见
- putenv() - Sets the value of an environment variable
- apache_getenv() - Get an Apache subprocess_env variable
- Superglobals
