$_ENV -- $HTTP_ENV_VARS [deprecated] — Environment variables
These variables are imported into PHP's global namespace from the environment under which the PHP parser is running. Many are provided by the shell under which PHP is running and different systems are likely running different kinds of shells, a definitive list is impossible. Please see your shell's documentation for a list of defined environment variables.
|4.1.0||Introduced $_ENV that deprecated $HTTP_ENV_VARS.|
Example #1 $_ENV example
<?php echo 'My username is ' .$_ENV["USER"] . '!'; ?>
Assuming "bjori" executes this script
The above example will output something similar to:
My username is bjori!
This is a 'superglobal', or automatic global, variable. This simply means that it is available in all scopes throughout a script. There is no need to do global $variable; to access it within functions or methods.