Writing CICS TCP/IP applications

Introduction to CICS TCP/IP describes the basics of TCP/IP client/server systems and the two types of server: iterative and concurrent. This topic considers in detail four TCP/IP setups in which CICS® TCP/IP applications are used in various parts of the client/server system.

The setups are:

The client-listener-child server application set. The concurrent server and child server processes run under CICS TCP/IP. The concurrent server is the supplied listener transaction. The client might be running TCP/IP under one of the various UNIX operating systems such as AIX®.
Writing your own concurrent server. This is the same setup as the first except that a user-written concurrent server is being used instead of the IBM® listener.
The iterative server CICS TCP/IP application. This setup is designed to process one socket at a time.
The client CICS TCP/IP application. In this setup, the CICS application is the client and the server is the remote TCP/IP process.

For details of how the CICS TCP/IP calls should be specified, see C language application programming, Sockets extended API, and Original COBOL application programming interface (EZACICAL).