AR/CTL supports all QUICKSTART calls, including checkpoint calls in subprograms. AR/CTL provides the Subprogram Virtual Storage (ARCSPVS) application program interface (API) for managing defined areas of virtual storage for any application program, including a subprogram, in a restartable environment. If an application subprogram already uses the subprogram support that is provided with the QUICKSTART for MVS product, no program changes are required for the use of AR/CTL support for subprograms.
For support of rollback checkpoint calls, you can use AR/CTL application reattach options. A rollback-type call forces a user abend, which causes changes to be backed out. AR/CTL treats a restart as a result of a rollback as it does any other restart. If you set up application reattach options and ensure that a restart from the beginning of the UOW is valid, a rollback-type call restarts application processing automatically at the last checkpoint.
Conversion of an existing QUICKSTART program to work with AR/CTL is a simple process that involves no application program changes. For more information, see Customizing after installation.