// The modbus_get_response_timeout() function shall return the timeout interval used to wait for a response in the to_sec and to_usec arguments.
func (this *RtuConnection) Get_response_timeout() (time.Duration, error) {
	var to_sec, to_usec C.uint32_t

	res, errno := C.modbus_get_response_timeout(this.ctx, &to_sec, &to_usec)
	if int(res) == 0 {
		return time.Duration(to_sec)*time.Second +
			time.Duration(to_usec)*time.Microsecond, nil
	} else {
		return 0, errors.New(modbus_strerror(errno))
	}
}
func (this ModbusRTUConnection) Timeout() time.Duration {
	var sec, usec C.uint32_t
	C.modbus_get_response_timeout(this.ctx, &sec, &usec)
	return time.Duration(sec)*time.Second + time.Duration(usec)*time.Microsecond
}