instance method writing

# File activesupport/lib/active_support/encrypted_file.rb, line 59
      def writing(contents)
        tmp_file = "#{Process.pid}.#{content_path.basename.to_s.chomp('.enc')}"
        tmp_path = Pathname.new File.join(Dir.tmpdir, tmp_file)
        tmp_path.binwrite contents

        yield tmp_path

        updated_contents = tmp_path.binread

        write(updated_contents) if updated_contents != contents
      ensure
        FileUtils.rm(tmp_path) if tmp_path.exist?
      end