Daily-planning-scheduling environment exit EQQDPX01

The daily-planning-scheduling environment exit (EQQDPX01) is called by the IBM® Tivoli® Workload Scheduler for z/OS® daily-planning batch jobs and is used to set or modify the scheduling environment names associated to the operations in the plan.

This exit can be invoked for all new operations that do not run on a fault-tolerant workstation. The exit is optional: the daily plan batch attempts to load it, and when it finds it, it puts it to use. The exit should be used with care as it could affect system performance.

Installing the exit

The load module implementing this exit must be link-edited into an APF-authorized library in the LNKLST concatenation or defined by the STEPLIB DD statement in the Tivoli Workload Scheduler for z/OS JCL procedure.

If the load module performs any input or output, it must be link-edited with RMODE(24) according to normal z/OS restrictions. Otherwise, it can be link-edited with RMODE(ANY). Tivoli Workload Scheduler for z/OS invokes the exit in AMODE 31. The AMODE parameter specified at link-edit time has no effect.

Interface to the exit

This exit is invoked in task mode, problem state, and key 8 and the job-step task is APF-authorized. The active task runs with the same access authority as the job-step task. The exit must restore this state before returning to its caller. Control is passed to the exit using the BAL instruction. The exit must return to its caller using the address and addressing mode passed to it, usually register 14.

The exit is entered in AMODE 31 but must switch to AMODE 24 before performing any input or output operations, and then switch back to AMODE 31 before returning to the caller.

When the exit is entered, register 1 contains the address of the parameter list. Each address in this list is used to locate the parameter value. These parameters are passed to the exit:

EQQDPX01 parameters

 FUNC      DS   CL6       (Function type)
 ADID      DS   CL 16     (Name of current application)
 OPNUM     DS   F         (Operation number)
 JOBNAME   DS   CL8       (Job name)
 WSNAME    DS   CL4       (Operation workstation name)
 SPECNR    DS   H         (Number of special resources)
 SPECBUF   DS   A         (Special resource buffer)
 WSCHENV   DS   CL 16     (Scheduling Environment Name)
 MCAUSERF  DS   A         (User field)

FUNC

Function type:

'INIT ' first call
'TERM ' last call
'CHECK ' check SCHENV call

The exit is called at DP batch start with function type INIT and at DP batch end with function type TERM. This is so that the open and the close only at the beginning and at the end of DP batch (to minimize impact on performance). The exit is called with function type CHECK each time an operation must be checked.

FUNC

Is present only for compatibility reasons.

ADID

Is the name of the application that the job belongs to.

OPNUM

Is the operation number of the operation representing this job.

JOBNAME

Is the name of the job associated to the operation.

WSNAME

Is the name of the workstation where the operation is to run.

SPECNR

Is the number of special resource names in SPECBUF.

SPECBUF

Is an address to a buffer that contains a number of 64-byte fields. The number of 64-byte fields in the buffer is indicated by SPECNR. The first 44 bytes of each field contain the name of the special resource. The last 20 bytes of each field are reserved for future use.

WSCHENV

Is the scheduling environment name currently stored in the CP operation record. This value can be modified by the exit.

MCAUSERF

This field is reserved for users. Tivoli Workload Scheduler for z/OS does not use or update it.