public function getDefaultOwner($usePosix = false)
    {
        $defaultPermissions = $this->getDefaultPermissions();

        $owner = $defaultPermissions['user'];
        if (empty($owner) && $usePosix) {
            $owner = function_exists('posix_getuid') ? posix_getuid() : null;
        }

        if (empty($owner)) {
            return false;
        }

        return $owner;
    }