Application-initiated TMF transactions

IBM® MQ for HPE NonStop V8.1 supports application-initiated TMF transactions in the same way that WebSphere MQ for HP NonStop Server V5.3 on NonStop does.

An MQPUT or MQGET operation with syncpoint option set, and called while a user-initiated TMF transaction is active, results in the queue manager inheriting the application-initiated transaction. All file operations to the queue data files are completed under the control of the application-initiated transaction.

When no application-initiated transaction is active, IBM MQ implicitly starts a TMF transaction when required. When functions like MQGET or MQPUT are called and the SYNCPOINT option is set, MQCMIT or MQBACK must be called to terminate the implicitly started transaction. The rules are the same as for IBM MQ on other platforms. At any point in time either an application-initiated transaction, or an implicitly started MQ transaction might be active. Trying to mix those will result in an error with reason code MQRC_UOW_MIX_NO_SUPPORTED (2355).

The general platform-specific rules are the same as for WebSphere MQ V5.3 on NonStop, so existing applications using application-initiated TMF transactions will continue to work without change.

IBM MQ for HPE NonStop V8.1 native applications support multiple API calls against different queue managers within a single TMF transaction.