code/libraries/joomlatools/library/user/session/abstract.php
public function isActive()
    {
        $sid = defined('SID') ? constant('SID') : false;
        if ($sid !== false && session_id()) {
            return true;
        }

        if (headers_sent()) {
            return true;
        }

        return false;
    }
public function isActive()
    {
        $sid = defined('SID') ? constant('SID') : false;
        if ($sid !== false && session_id()) {
            return true;
        }

        if (headers_sent()) {
            return true;
        }

        return false;
    }
public function isActive ( ) { $ sid = defined ( 'SID' ) ? constant ( 'SID' ) : false ; if ( $ sid !== false && session_id ( ) ) { return true ; } if ( headers_sent ( ) ) { return true ; } return false ; }
Is this session active

@return boolean  True on success, false otherwise
Is this session active