The application programming interfaces provide access to CICS COMMAREA programs, CICS channels and containers programs, and 3270 programs.
APIs are included for the Java and C programming languages. JCA resource adapters, and a .NET API for use in remote mode topologies are also included. Using these APIs, client applications can make multiple concurrent program calls to one or more CICS servers. Applications developed in C++ and COBOL languages can call the C API.
The ECI enables client applications to send requests to CICS COMMAREA and channel programs.
The ECI is available in all supported runtime environments. ECI is the most commonly used mechanism for providing client access to CICS. An ECI request results in a CICS distributed program link (DPL) call to the target program and must follow the CICS rules of the DPL subset.
JEE applications using the ECI resource adapter can access CICS resources as part of a two-phase commit transaction.
The ESI enables client applications to call CICS password expiry management (PEM) functions. Client applications can access information about user IDs that are held in the CICS External Security Manager (ESM) through this interface.
The statistics API enables applications to obtain dynamic, real-time statistical information about the runtime performance of CICS Transaction Gateway. Applications can be written in C or Java.
Sample applications written in the supported programming languages are provided for all programming interfaces. For more information about working with the APIs, see Application programming interfaces.