IMS Connect user message exit routines

For most types of IMS Connect clients, IMS Connect requires the use of a user message exit routine to manage the messages that are received from and sent to the client.

The user message exit routines can perform a number of tasks related to the management of messages, including:
  • Translating input messages into the protocol or format required by IMS and the IMS Open Transaction Manager component
  • Rerouting messages
  • Checking security for input messages
  • Returning user-defined messages in response to certain user-defined criteria

For security checking, the IMS Connect user message exit routines allow you to call IMSLSECX, the security message exit routine, issue the RACF® function in these user message exit routines, or use the IMS Connect user RACF function.

This topic contains Product-Sensitive Programming Interface and Associated Guidance Information.

Note: Do not issue any MVS™ calls in the user message exit that result in an MVS WAIT because the MVS WAIT will halt all work on the port. If you modify the user message exit routine and add code that results in an MVS WAIT, all work on the TCP/IP PORT will halt until the WAIT has been posted. The user message exit routines cannot be modified to free any storage passed to the exit routine, and IMS Connect will not free any storage obtained by the user message exit routine when the exit routine returns to IMS Connect. All storage obtained by IMS Connect must be released by IMS Connect and cannot be freed by the user message exit routine without causing failures.