code: func Path(p ...string) (string, error) {
  	path := filepath.Join(append([]string{Dir()}, p...)...)
  	if !strings.HasPrefix(path, Dir()+string(filepath.Separator)) {
  		return "", errors.Errorf("path %q is outside of root config directory %q", path, Dir())
  	}
  	return path, nil
  }
docs: // Path returns the path to a file relative to the config dir