PHP Predefined Constants Posted byProsoxi.com Webmaster March 5, 2011March 5, 2011 Leave a comment on PHP Predefined Constants The constants below are defined by this extension, and will only be available when the extension has either been compiled into PHP or dynamically loaded at runtime. DIRECTORY_SEPARATOR (string) PATH_SEPARATOR (string) <?php require_once (‘public’ . DIRECTORY_SEPARATOR . ‘index.php’); ?>