Other system routines that process output data sets
Output data sets placed on the output service writer or hold queue can be processed by applications written to exploit the SYSOUT application programming interface (SAPI). The selection of SYSOUT from the writer or hold queue will be in accordance with the use of the SAPI as defined in z/OS MVS Using the Subsystem Interface.
Output data sets placed on the output service hold queue are processed
by the following system routines:
- External writer: An external writer is an MVS™ routine that handles output destined for devices not supported by JES3 output service, such as DASD or magnetic tape devices. For information about controlling external writers, see z/OS MVS System Commands.
- Internal reader: The internal reader is a JES3 routine that passes output data sets containing job streams to JES3 input service for processing. For information on controlling the internal reader, see Controlling job input and converter/interpreter service.
- TSO/E OUTPUT command processor: The TSO/E OUTPUT command processor is an MVS routine that handles output destined for a TSO/E user. For information about using the OUTPUT command, see z/OS TSO/E Command Reference.