MQSeries.net :: View topic - Problem with timed-out GET command on queue

mikehkk · Posted: Wed Dec 17, 2003 8:30 am Post subject:

I have a VB application using MQSeries COM objects. The app's generic getMessage() method has an optional parm passed to it specifying the time interval that a GET command will "hold" on a queue - after which it releases its grip if there are no messages to be had (to prevent an infinite "blocking" GET in other words).

When this method was first coded, what was odd is that sometimes MQ would generate error-like behavior during the message-less, timed GET. Examination of the MQ Session object's .Reason property value in the error handler invariably had either of the two values:

MQRC_NONE or MQRC_NO_MSG_AVAILABLE

I never understood why this error-like behavior was being raised however. It was random too, no consistency about it.

Anyway, I put the following hack in the procedure's error handler to test for the above "error" circumstance:

'Test to see if an event was raised that is really an error condition...
If (MQSession.ReasonCode = MQRC_NONE Or MQSession.ReasonCode = MQRC_NO_MSG_AVAILABLE) Then
'No error, code here creates a normal exit from method...
Else
'There was a real error of some kind (continue raising an error)
End If

And the above code did its job... until recently however. Now the same thing is happening - but with a twist: The "error" test is failing in the first If() evaluation and winding-up in the Else() case. However, the Session.ReasonCode() property value there still reads MQRC_NONE or MQRC_NO_MSG_AVAILABLE.

Has anyone encountered this behavior before? Is there some property I'm not setting(could be set?) on the queue at it's creation that would prevent this behavior in the first place? Make the queue's operation more robust?

Appreciate any and everyone's two cents on this. Thanks!