Q:

Using facebook js sdk how to get user permission popup

I tried this but i'm not getting the pop up.
FB.login(function(response)
{
    if (response.session)
    {
        if (response.perms)
        {
            alert('user is logged in and granted some permissions: ' + response.perms);
        }
        else
        {
            alert('logged in but didnt grant permissions');
        }
    }
    else
    {
        alert('not logged in');
    }
},
{perms:'publish_stream'});

A:

Are you sure that this 
{perms:'publish_stream'}

is right?
I would rather put 
{scope:'publish_stream'}

