ZDMClient uses mqtt (from what I’ve seen) and, as default, mqtt publish does not directly send data to the end point, it just stores them in a buffer and then sends them.
So you have to manually check if the data has been published or not.
As of now, there is no way to see this in the ZDMClient library. I’ve seen that I need to use sleep between publish and unlink to give time to the mqtt thread to send data correctly. Yes, I’ve checked and no data is stored if I don’t use the sleep function.
Also there’s the issue about exceptions being thrown by a thread (which is is thread that handles mqtt connection) that makes my firmware reset when I unlink my wifi.
For this too, there’s no way I could catch that exception, except if I disconnect my mqtt client before making the unlink call.
I hope I explained everything, I’m here to clarify