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[xmlblaster] Newbie Question.


xmlBlaster looks great. I am attempting to wrap my head around some of the
semantics of using Pub/Sub pattern as applied in xmlBlaster. I am little
more familiar with the Event/Notification services of CORBA. By the way I
have TAO using xmlBlaster, very nice and easy thanks jacorb and TAO.

Anyway to my question. I am using SimpleChat that is using Pub/Sub as a
tutorial, why is it that everytime I connect to xmlBlaster I get the last
message published. If I post a single message and then disconnect and
reconnect a few times I will seem to recv as many messages via update()
invocations at startup. I'm not quite getting what is happening here.

If I on client A press "Who is there"
On client B I will see "I am retrieving the connected users list (ignore
this)" for as many times as I connect and logout.

What am I is missing.

I am grappling with xml and the manner in which it used with xmlBlaster
(I'll get there soon enough). Is this some sort ot Qos thing? Where can I
read of what Qos is available for Pub/Sub and what are the xml attributes
names for setting Qos up?

Also I am having trouble with MessageUnit on C++ is I believe lifetime
management of the objects is not quite right.
If MessageUnit is on the stack and then passed in a call to publish(), hmmm
perhaps this is a valueType thing since MessageUnit is a struct and I havent
compiled the idl properly I'll let you know.

look forward to your reply.


Martin Johnson