Disconnection not detected properly

[AmineG]

I tried to display the MQTT client status, by showing the value of "connected" Boolean.
What I notice when I close any network connection, the MQTTKit does not detect the connection interruption (I tried to close wifi, and I was observing "connected" bool changes).
I think some reachability checking code can be added to enhence the connection loss detection.

(If I play the same scenario with MQTTClient framework, it detect that MQTT connection is lost.)

[sxhebing]

I have same question!