file download attachment

gistfile1.php

<?php
function download_file($adress){
  $adress = str_replace('+',' ',$adress);
  $file = d()->File->where('title = ?',$adress);

  header('Content-Description: File Transfer');
  header('Content-Type: application/octet-stream');
  header("Content-Disposition: attachment; filename*=UTF-8''".rawurlencode( $file->title).'.'.$file->ext."");
  header('Content-Transfer-Encoding: binary');
  header('Expires: 0');
  header('Cache-Control: must-revalidate');
  //header('Pragma: public');
  //header('Content-Length: ' . filesize($file));
  ob_clean();
  flush();
  readfile($_SERVER['DOCUMENT_ROOT'] . $file->file);
  exit();
  print $file->ext;
  print $file->file;
}