private static function cfgGetDefaultName()
    {
        $nameDefault = null;
        $sessionNamePref = array('SESSIONID', \session_name());
        foreach ($sessionNamePref as $nameTest) {
            $useCookies = isset(self::$cfgExplicitlySet['useCookies'])
                ? self::$cfgExplicitlySet['useCookies']
                : self::$cfgStatic['useCookies'];
            if ($useCookies && !empty($_COOKIE[$nameTest])) {
                $nameDefault = $nameTest;
                self::$status['requestId'] = $_COOKIE[$nameTest];
                break;
            }
            $useOnlyCookies = isset(self::$cfgExplicitlySet['useOnlyCookies'])
                ? self::$cfgExplicitlySet['useOnlyCookies']
                : self::$cfgStatic['useOnlyCookies'];
            if (!$useOnlyCookies && !empty($_GET[$nameTest])) {
                $nameDefault = $nameTest;
                self::$status['requestId'] = $_GET[$nameTest];
                break;
            }
        }
        if (!$nameDefault) {
            $nameDefault = $sessionNamePref[0];
        }
        return $nameDefault;
    }