The context containers

In some situations, user-written message handler programs, and header processing programs, need information about the context in which they are invoked. CICS® provides this information in a set of context containers which are passed to the programs.

CICS initializes the contents of each context container, but, in some cases, you can change the contents in your message handler programs, and header processing program. For example, in a service provider pipeline in which the terminal handler is one of the CICS-provided SOAP handlers, you can change the userid and transaction ID of the target application program by modifying the contents of the appropriate context containers.

Some of the information provided in the containers applies only to a service provider, or only to a service requester, and therefore some of the context containers are not available in both.