def chmod(mode = nil)
      return unless mode
      begin
        Integer mode
        mode = Integer mode.size == 3 ? "0#{mode}" : mode
      rescue ArgumentError
      end
      FileUtils.chmod mode, selected_items.map(&:path)
      ls
    end
def chmod(mode = nil)
      return unless mode
      begin
        Integer mode
        mode = Integer mode.size == 3 ? "0#{mode}" : mode
      rescue ArgumentError
      end
      FileUtils.chmod mode, selected_items.map(&:path)
      ls
    end
Change the file permission of the selected files and directories.

 ==== Parameters
 * +mode+ - Unix chmod string (e.g. +w, g-r, 755, 0644)