title: How can i login without permission dialog on facebook with ios sdk?
body: <p>in my application on iphone when i call </p>
  
  <pre><code>[facebook authorize:permissions delegate:self];
  </code></pre>
  
  <p>the framework show login dialog automatically if i'm not loggedin, and then show permission dialog (This is great for the frist time that a user use the application).
  But if i've aleady get permission i always show the dialog with message "You have aleady authorized this application". <br/><br/>
  So, how can i login without show permission dialog? Or can i check if i've aleady get permission to the application?<br/>
  In the framework sample code the only way to login is by authorize method...</p>
  
  <p>Thanks in advance.</p>