How to integrate arrowchat

Hi i installa arrowchat with wordpress integration but when i go online i cant retreive user online, che u help tu get user id to show up who is online? please thanks in andvance for your help the code is simple

function get_user_id()
{
$userid = NULL;

if (!empty($_SESSION[‘userid’]))
{
$userid = $_SESSION[‘userid’];
}

return $userid;
}

or

function get_user_id()
{
$userid = NULL;

if (!empty($_COOKIE[‘userid’]))
{
$userid = $_COOKIE[‘userid’];
}

return $userid;
}