public function chown($files, $user, $recursive = false)
    {
        foreach ($this->toIterable($files) as $file) {
            if ($recursive && is_dir($file) && !is_link($file)) {
                $this->chown(new \FilesystemIterator($file), $user, true);
            }
            if (is_link($file) && \function_exists('lchown')) {
                if (true !== @lchown($file, $user)) {
                    throw new IOException(sprintf('Failed to chown file "%s".', $file), 0, null, $file);
                }
            } else {
                if (true !== @chown($file, $user)) {
                    throw new IOException(sprintf('Failed to chown file "%s".', $file), 0, null, $file);
                }
            }
        }
    }