Defining a CICS Transaction Server for z/OS data structure

Mapped data structures, such as COBOL copybooks or C structures, can be used to define an MRM message definition for a CICS® Transaction Server for z/OS® COMMAREA or a channel container.

Before you begin

About this task

After you have created the message definition, complete the following steps.


  1. Select the Data structure property value on the Basic tab of the CICSRequest node in accordance with the targeted CICS program. For example, if the target program is channel-based, select Channel as the data structure.
  2. Ensure that the properties on the Response Message Parsing tab of the CICSRequest node specify the output COMMAREA or container structure.
  3. Check that the upstream nodes are configured to provide the correct input structure.
  4. Optional: If you are using a COMMAREA data structure, ensure that the CICSRequest node Commarea length property is large enough to hold the serialized input or output structures to avoid a memory leak in the CICS application.

What to do next

If you are using a channel data structure, create a message collection to represent the channel data structure, as described in Creating a message collection by using ESQL.