Token class not returning the Error Message details of connectionFailure

[ShankarPendyala]

The native library is providing Reason code, return code and error message details. However, these details got suppressed in the token class.
Application callback are getting token objects and which has public method to get ReasonCode and ReturnCode but not the error message.
Few observations: For Connection Failures, most of the times paho returning ReasonCode:255 and Return Code: -1
This information is insufficient to find out the actual cause of connection failure, the failure may be due to network issue, certificate issue, TLS hand shake error , socket error etc

No proper reason code or error message available to extract this info.

Can someone please clarify our understanding and suggest how to get the relevant info on connection failures?

[fpagliughi]

This is a problem with the upstream Paho C library that I would really like to get fixed. That library often determines the problem, logs it, then doesn't pass that information back up to the caller... which in this case is the C++ library wrapper and your application. I have an old issue in that library requesting additional details...

eclipse-paho/paho.mqtt.c#937

The string message that sometimes bubbles up from the library might have a little more info, but is still pretty vague. I can look at adding that if it might help.