title: PHP is ignoring my HTTP_REFERER
body: <p>i created a login and signup system with files like : 
  <code>register.php</code> action for the form is <code>do_register.php</code>
  <code>login.php</code> action for the form is <code>do_login.php</code>
  and i don't want the user to access the <code>do_register.php</code> or the <code>do_login.php</code> only if they are redirected by <code>register.php</code> or <code>login.php</code>.
  so i though about bloking access via HTTP_REFERER here is the lines:</p>
  
  <pre><code>$refer=$_SERVER ['HTTP_REFERER'];
  if($refer!= "http://www.example.com/register.php")
  {
  header("location:index.php");
  }
  </code></pre>
  
  <p>but the problem that it is not blocking the access .</p>