Reading Facebook wall returns an empty array

I am t开发者_开发技巧rying to read a user's wall, not news feeds, with PHP, and I always get an empty array from this:

$api_call = array(
    'access_token'=>$facebook->getAccessToken()
);

try{
    $wall= $facebook->api("$uid/feed/","get",$api_call);
} catch (Exception $e){}

Any idea what is wrong here?

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You need to have the read_stream extended permission if you want to see posts other than those with visibility set to 'Public'