posix_getlogin() will return boolean false when there is no shell, e.g. when running under an apache process
(PHP 4, PHP 5, PHP 7, PHP 8)
posix_getlogin — Return login name
Returns the login name of the user owning the current process.
This function has no parameters.
Example #1 Example use of posix_getlogin()
<?php
echo posix_getlogin(); //apache
?>