Our process needs to read messages from a topic on the local Q manager and also write to a different topic on the same local Q manager.
To read messages we have used MQCB. The messages reach the callback function of the process. However, while the callback remains registered, we are not able to MQPUT messages to a different topic.
We get an error that says:
2500 : MQRC_HCONN_ASYNC_ACTIVE
An attempt to issue an MQI call has been made while the connection is started
Apparently, a single connection handle cannot be used to both read and write. We have to Suspend the MQCB, MPUT the message and Resume the MQCB to get it to work.
Is there a way to avoid having to suspend and resume?
Thanks in advance
Yes, that is the expected behavior when using MQCB. Two approaches you can take:
1) Create another connection to the same queue manager to publish messages.
2) If your design is to publish messages whenever you receive a message on the callback function, then publish messages from callback function itself.
Update
MQRC_ALREADY_CONNECTED (2002) issue: What MQCNO_HANDLE_SHARE_* option have you used? Suggest you to use MQCNO_HANDLE_SHARE_BLOCK option to get around this problem. I wrote a sample program and created two connections on the same thread by using MQCNO_HANDLE_SHARE_BLOCK option.