title: How to ask for extra permission from my current facebook app users?
body: <p>i am using this code to ask users for permission for my app</p>
  
  <pre><code> $app_id = "1231654321654121";
   $canvas_page = "http://apps.facebook.com/manydldotnet/";
   $auth_url = "https://www.facebook.com/dialog/oauth?client_id=" . $app_id . "&amp;redirect_uri=" . urlencode($canvas_page) . "&amp;scope=email,read_stream";
  
   $signed_request = $_REQUEST["signed_request"];
  
   list($encoded_sig, $payload) = explode('.', $signed_request, 2); 
  
   $data = json_decode(base64_decode(strtr($payload, '-_', '+/')), true);
  
   if (empty($data["user_id"])) {
          echo("&lt;script&gt; top.location.href='" . $auth_url . "'&lt;/script&gt;");
   }
  </code></pre>
  
  <p>but now i need to ask the CURRENT users for "publish_stream" permission,
  I added the "publish_stream" permission to the scope parameter but it is not working for the users already gave the app a permission before.</p>
  
  <p>so how can i fix this?</p>
  
  <p>thanks...</p>