public function actionDefault($scheme, $dir)
 {
     if (preg_match('/^[a-z0-9]+$/i', $this->scheme)) {
         $this->scheme = $scheme;
         $this->fileSystem = Wrapper::getRegisteredWrapper($this->scheme);
     }
     $this->dir = rtrim($dir, '/') . '/';
     if (!$this->fileSystem instanceof FileSystem) {
         echo 'Unkown filesystem ' . $this->scheme . '://. Is it registered?';
         $this->terminate();
     }
 }