August Zajonc wrote:
I've got a quick beginner question.
I've got a consumer. When it's done working it checks to see if
anything else is waiting in the private queue that it's using. If
there is nothing waiting, it just wants to listen (with a callback or
similar) rather than spin in a loop burning cycles.
It wants any messages received after it's last inquiry to trigger the
callback (to avoid a race where it checks, a message then arrives,
then it starts listening, but leaves that message orphaned). The trick
though is that there is only 1 consumer, and if it's processing a
message, it'd prefer not to receive a callback for new ones until it
is again "IDLE".
What's the classic way to handle this? Is this built in, or do a I
need to set the callback to something that manages my consumer and
keeps track of consumer state.
- August
Note sure what language you are using, but here is an example in c++
client of what you are wanting to do
https://svn.apache.org/repos/asf/incubator/qpid/trunk/qpid/cpp/examples/pub-sub/topic_listener.cpp
if you are using another language, shout and we can point you the
respective example.
regards
Carl.
