Function esp_idf_sys::esp_transport_poll_read

pub unsafe extern "C" fn esp_transport_poll_read(
    t: esp_transport_handle_t,
    timeout_ms: c_int
) -> c_int

@brief Poll the transport until readable or timeout

@param[in] t The transport handle @param[in] timeout_ms The timeout milliseconds (-1 indicates wait forever)

@return - 0 Timeout - (-1) If there are any errors, should check errno - other The transport can read