Description:
------------
I noticed that realpath() function does not return the same result when called during the regular script execution and in the shutdown process.

This behavior only appears when PHP is running as Apache module, but not in CGI/FastCGI mode.

Tested with PHP 5.2.6, 5.3.0, 4.4.8.

Reproduce code:
---------------
<?php

function MyShutdownFunc() {
    echo realpath("./") . "<br />";
}

MyShutdownFunc();

register_shutdown_function("MyShutdownFunc");

?>


Expected result:
----------------
/www/mysite.com/staging/root
/www/mysite.com/staging/root


Actual result:
--------------
/www/mysite.com/staging/root
/