Requesting IBM Z Workload Scheduler service
- Event-tracking routines. These are versions of standard z/OS and JES exits that are supplied by IBM Z Workload Scheduler and that invoke services by issuing the EQQEXIT macro. The EQQEXIT macro generates code to invoke IBM Z Workload Scheduler services correctly.
- TSO users running IBM Z Workload Scheduler dialogs in an ISPF environment. The dialogs invoke IBM Z Workload Scheduler services by calling the TSO service facility, which in turn calls the EQQMINOP module. The EQQMINOP module is APF-authorized and is able to use the z/OS subsystem interface to request service from IBM Z Workload Scheduler.
- The IBM Z Workload Scheduler server handles requests from remote dialog users or PIF applications, or from the GUI. The requests are forwarded to the subsystem via the EQQMINOP module, that uses the z/OS® subsystem interface.
- The program interface, the batch loader, and the event generation program (EQQEVPGM).
Requests for IBM Z Workload Scheduler subsystem services can also be made through the application programming interface (API).
As a result of calling the z/OS subsystem interface, the module EQQSSCMP is invoked. This module is loaded during the master scheduler initialization and resides in the link pack area (LPA) or CSA, depending on whether it is loaded from SYS1.LPALIB or SYS1.LINKLIB. The EQQSSCMP routine provides the interface to the IBM Z Workload Scheduler address space.
If the service requester is an event-tracking routine, the EQQSSCMP module is called once for each IBM Z Workload Scheduler subsystem that is defined. If the service requester is an IBM Z Workload Scheduler dialog, the EQQSSCMP module is called only for one specific subsystem determined by the subsystem name that the TSO user has defined in the dialog initialization panel.
If EQQSSCMP is called for a job-tracking event, an exit event record is built and added to an IBM Z Workload Scheduler queue that is serviced by the event writer (EW) subtask. (This subtask is described in Event writer (EW). The job-tracking caller does not wait for service from the event writer. Instead, the job-tracking caller returns after updating the EW queue.
If EQQSSCMP is called for a dialog service request, an entry is added to an IBM Z Workload Scheduler queue that is serviced by the general service (GS) subtask. (This subtask is described in General service (GS).) If a GS subtask is active, the request is dequeued and processed. The dialog user caller waits for service from the GS subtask. When the service is performed, the GS subtask posts the waiting dialog. The EQQSSCMP module then returns to EQQMINOP, which in turn returns to the IBM Z Workload Scheduler dialog.