title: PHP alternative to session_is_registered
body: <p>does anyone knows the alternative to the deprecated function session_is_registered in PHP5?</p>
  
  <p>here's my code:</p>
  
  <pre><code>ob_start();
  
  session_start();
  
  if(!session_is_registered(myusername))
  
  {
  
      header("location:main_login.php");
  
  }
  
  ob_flush();
  </code></pre>
  
  <p>Thanks,</p>
  
  <p>Mauro</p>