Creating Custom APIs

This appendix shows how an installation can add APIs to the server to provide capabilities that are not provided by the IBM-supplied APIs. This is done through a three-step process, as follows:

1. Determine the API design (name, input and output parameters, and type).
2. Write a custom exec (in REXX) to perform the desired task.
3. Install the custom exec on the server.

A client program calls the locally-defined API in the same manner as an IBM-supplied API, with the appropriate input parameters. The server checks the authorization file and, if the client is authorized, a worker server calls the custom exec with certain input arguments. The custom exec performs the desired task and returns with a certain return value. The server then returns the appropriate output parameters to the client program.