This will get the user object which can be used to retreive user’s access level code. This code is in the gid field in jos_users table.
$user = &JFactory::getUser();
$access = $user->get('gid',0);
Group access level codes:
Backend Admin Access
25 – Super Administrator
24 – Administrator
23 – Manager
Front End Access
21 – Publisher
20 – Editor
19 – Author
18 – Registered
21 – Publisher
UPDATE: As of Joomla 1.6 the gid field in jos_users table is no longer available.
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