err := jd.Open()
	if err != nil {
		return err
	}

	b, err := je.MarshalMsg(nil)
	if err != nil {
		return err
	}

	jd.Lock()
	defer jd.Unlock()
	_, err = jd.file.Write(b)
	if err != nil {
		// Do not leak fd here, close the file properly.
		Fdatasync(jd.file)
		_ = jd.file.Close()

		jd.file = nil // reset to allow subsequent reopen when file/disk is available.
	}
	return err