Perchè secondo voi questo avviso.

Notice: Use of undefined constant _FILE_ - assumed '_FILE_' in C:\vhosts\tshirtshop\include\config.inc.php on line 3



<?php
// SITE_ROOT contains the full path to the tshirtshop folder
define ("SITE_ROOT", dirname(dirname(_FILE_)));
// Setting needed to configure the Smarty template engine
define("SMARTY_DIR", SITE_ROOT."/libs/smarty/");
define("TEMPLATE_DIR", SITE_ROOT."/templates");
define("COMPILE_DIR", SITE_ROOT."/templates_c");
define("CONFIG_DIR", SITE_ROOT."/configs");
?>

Vi ringrazio.