pub unsafe extern "C" fn esp_mqtt_client_unsubscribe(
    client: esp_mqtt_client_handle_t,
    topic: *const c_char
) -> c_int
Expand description

@brief Unsubscribe the client from defined topic

Notes:

  • Client must be connected to send unsubscribe message
  • It is thread safe, please refer to esp_mqtt_client_subscribe_single for details

@param client MQTT client handle @param topic

@return message_id of the subscribe message on success -1 on failure