Controlling output processing

Once a job has finished processing, JES3 output service handles the job's output. Each output data set is associated with a SYSOUT class. Your installation can group output data sets into as many as 36 different classes: A through Z and 0 through 9. Each class consists of all system messages and output data sets the system associates with that class name. This permits your installation to group output data with common characteristics. When a job's data sets are passed to output service, JES3 places each data set on the output queue defined by your installation for the data set's SYSOUT class.

JES3 scans the data sets on the output service writer queue to match the data sets' output requirements against the characteristics of either an active JES3 output service writer that is waiting for work or with an output device. Output service writers are associated with specific JES3 print or punch devices. If a match is found with an active writer, JES3 passes the data set to the writer and the writer produces the output on an associated device. If a match is found with a device, JES3 dynamically activates a writer that can control the device and produce the output.

Output service writers generally are supported directly by JES3. Devices controlled by these writers must be attached to the JES3 global. Some output service writers, however, are supported by functional subsystems (FSS) which perform some JES3 functions (see Controlling JES3 services). Such a writer can control the AFP printers. If controlled by an FSS output service writer, the AFP printers can print data sets containing embedded controls to format data on a printed page. Although these devices remain JES3-managed, they can be attached either to the global or a local main, depending on which main the FSS is associated with. (If an output device has the same device address as another device on a different main, you must address that device using the JNAME defined during initialization.)

Writer output processing also can run in parallel with other JES3 functions on a tightly-coupled global by using the writer output multitasking facility. Once a writer has selected a data set queue, output processing can run at the same time as other JES3 functions.