Php putenv() question

I am new to php. Can anyone give a good defi开发者_高级运维nition or example when to use putenv() in php? Thanks.

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The putenv function inside of PHP is used to set an environment variable inside the $_ENV[] global array. check out the php manual for more info: http://php.net/manual/en/function.putenv.php

Hope that helps, RayQuang