Stop subscribing to a specific MQTT topic or topics
|topics||String, blob or array of strings/blobs||
Topic(s) to be unsubscribed. Each must be valid UTF-8
Called when the broker responds to the unsubscribe request
This method allows you to end a subscription to one or more topics.
The callback function is executed when the agent receives an unsubscribe acknowledgement from the MQTT broker. It has one parameter, resultCode, into which an integer response code will be passed:
|-1||The unsubscription attempt failed|
An exception will be thrown if you call unsubscribe() on an mqttclient instance that is currently disconnected.