How do I get the list of mutual friends on Facebook using their API?

Question

I am trying to get a list of mutual friends of myself and another user but none of the API I found in the documentation works. Either I get some weird permission errors that I can only get my friends list and no other user or I get the following error:

Fatal error: Call to a member function friends_getMutualFriends() on a non-object in /home/app.php on line 27 

Is there a standard way that is used to get the total number of mutual friends or at least the list of friend ids of my friend?

Answer 1

Well it's actually friends.getMutualFriends().

Have a play here.

Answer 2

Ok... This one gave me a real hard time. I managed to do this using the Facebook JS SDK. Here's the snippet just in case anyone else wants to do this:

    FB.api(
          {
            method: 'fql.query',
            query: 'SELECT id FROM profile WHERE id IN (SELECT uid2 FROM friend WHERE uid1=me())'
          },
          function(response) {
            $.each(response, function(json) {
                console.info(response[json].id);
                        FB.api(
                          {
                            method: 'friends.getMutualFriends',
                            target_uid: 'INSERT ANOTHER FRIEND ID HERE'
                          },
                          function(response) {
                            console.info(response);
                          }
                          );
                return false;
            });

          }
        );