$Get variable losing content

[nikko500]

I am trying to retain information from the $get variable after checking if a user, (Joomla code), is logged in but it is not working. (url: http://domain.com/script.php?file=data)

 

define( '_JEXEC', 1 );
define( 'DS', DIRECTORY_SEPARATOR );
define('JPATH_BASE', '/path/to/joomla/dir/');
require_once ( JPATH_BASE .DS.'includes'.DS.'defines.php' );
require_once ( JPATH_BASE .DS.'includes'.DS.'framework.php' );
$mainframe =& JFactory::getApplication('site');
$mainframe->initialise();
$session =& JFactory::getSession();
$user =& JFactory::getUser();
// get username and name of user
$username = $user->get('username');
$name = $user->get('name');
if (empty($username)) {
    die('Not logged in');
}
   $file = $_GET['file'];
   echo &file;
   exit;

Any help appreciated.