Link3270 sample programs
CICS® provides sample client programs that use the ECI, EXCI and LINK interfaces to call the Link3270 bridge to run the sample transaction NACT. These sample programs provide coded examples that help you write your own client programs.
The sample transaction NACT has a well documented BMS interface.
The samples are not written to illustrate how a business client should process the data, so the business clients do not perform any special formatting of the data extracted from the user application.
The samples are designed to illustrate the two most common scenarios:
- Host Client
- The client program executes on the host system, using LINK or EXCI to drive the user
application. In this scenario, the sample programs show how you can divide the client logic
into a business-client that is concerned only with the business data and its
representation in the client end-user environment, and a bridge-client that
builds the bridge messages and manages the communication with the bridge. In this way, you can
develop the more complex back-end using CICS, and can
make it reusable.
The LINK and EXCI samples show how this common logic can be shared.
See Select Link3270 client scenarios for an illustration of the host client.
- Workstation Client
- The client program executes on a remote workstation, using ECI to drive the user
application. In this scenario, a single sample program is used, combining the business logic
in the client environment and the interface to the bridge. In this environment, the programmer
needs some, but not extensive, CICS knowledge.
See Select Link3270 client scenarios for an illustration of the workstation client.