def METHOD_NAME(self) -> None:
    """Start monitoring the udev stream.
    If the monitoring hasn't been started yet, this function will also
    check the file `state` in the UDC system folder to determine if the
    device is initially connected to a host or not; this is necessary due
    to the fact that udev messages regarding connection are only sent when
    the state changes.
    """
    if not self._monitor.started:
        # Check the `state` file to get an initial state setting
        LOG.debug(f"Monitoring platform/{self._phy_udev_name}")
        self._monitor.start()
        self._host_connected = self._read_state()