Strategies for Creating Service Programs
- Whether you intend to update the program at a later date
- Whether any updates will involve changes to the interface (namely, the imports and exports used).
If the interface to a service program changes, then you may have to re-bind any programs bound to the original service program. However, if the changes required are upward-compatible, you may be able to reduce the amount of re-binding if you created the service program using binder language. In this case, after updating the binder language source to identify the new exports you need to re-bind only those programs that use them.
TIP
If you are planning a module with only subprocedures (that is, with a module with keyword NOMAIN specified on the control specification) you may want to create it as a service program. Only one copy of a service program is needed on a system, and so you will need less storage for the module.
Also, you can copyright your service programs using the COPYRIGHT keyword on the control specification.
- Mask certain service program procedures from service-program users
- Fix problems
- Enhance function
- Reduce the impact of changes to the users of an application.
See Sample Service Program for an example of using binder language to create a service program.
For information on binder language, masking exports, and other service program concepts, see ILE Concepts.