check rc incase it is not no_more_msg

[parrobe]

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What

• Modified return from getMessageWithHObj to return the mqreturn error for later processing.
• Modified ProcessPublications() to verify error returned from getMessage() was MQRC_NO_MSG_AVAILABLE and if not return the error to the caller.

How

Added so that the metrics publication code would be able to detect other errors such as MQRC_Q_MGR_QUIESCING and so disconnect and stop the program from preventing the queue manager stopping.

Testing

Mnaual

Issues

Fixes #48

[sdmarshall79]

lgtm