Using client/server processing

CICS® business transaction services support client/server processing. These examples show you how BTS client/server processing works.

A server process is one that is typically waiting for work. When work arrives, BTS restarts the process, which retrieves any state data that it has previously saved. Typically, the client invokes the server with a named input event, and sends it some input data in a data-container. From these inputs, the server determines what actions it needs to take. It returns any output for the client in a data-container.

When the client has dealt with any output returned by the server, it releases the server process. Releasing the server means that its in-memory instance is freed. The server process is maintained only by BTS.

Client/server examples

The client/server examples in this section show:
  1. A client program initiating a server process and calling it with some work to do.
  2. The server defining some input events for which it might be invoked again; then performing some work and returning output to the client.
  3. After dealing with the output returned by the server, the client releasing the in-memory instance of the server.
  4. The client reacquiring the server process and requesting it to run again.
  5. The server process determining the input event that caused it to be invoked again, and retrieving some state data that it saved when it last ran; then performing some work and returning output to the client.
  6. Eventually, the client telling the server to shut down, and the server responding to this event by indicating that it must not be invoked again.

Subtopics

Parent topic: Interacting with BTS processes and activities

dfhp90t.html | Timestamp icon Last updated: Thursday, 27 June 2019