MFS Distributed Presentation Management output (SLU P)

IMS sends the entire output message as a single chain of one or more related transmissions. For MFS DPM output using a device format defined with paging OPTIONS=DPAGE or OPTIONS=PPAGE, IMS sends each logical or presentation page in a single chain of one or more related transmissions as if it were a complete message.

For MFS DPM output using a device format defined with paging OPTIONS=DPAGE or OPTIONS=PPAGE, IMS sends an output function management header as part of the first or only transmission of each chain (logical or presentation page) of the message. The remainder of the transmission contains data fields (DFLDs) up to the defined record length. This function management header contains the DPM version ID, DPAGE or PPAGE name, and a MID name if specified.

When a forms literal is defined in the DPM format specification for paging OPTIONS=DPAGE or OPTIONS=PPAGE (FORMS= parameter on the DEV statement), IMS precedes the first logical or presentation page with an only-in-chain transmission consisting of a function management header containing only the forms literal. No version ID, DPAGE name, or PPAGE name is provided. Output components are protected at the end of each output chain; this prevents IMS from sending subsequent output, or logical or presentation pages (chains), until an appropriate input message or control request is received.

For MFS DPM output using a device format defined with paging OPTIONS=MSG, IMS sends the entire message as a single chain of one or more related transmissions. The function management header is sent as the first or only transmission and contains the DPM version ID, format name, and any MID name or forms literal defined in the MFS format specification. In this case, as for non-DPM output, component protection is provided only if the destination component is defined as PROGRAM2.

For DPM, the device type symbolic name is specified to MFS as DPM-Xn, where X can be A or B. Message formatting is specified on the TERMINAL macro or on an ETO logon descriptor for logical units defined as SLU P by using device type symbolic names of the form DPM-An. DPM-Bn device type symbolic names refer to logical units defined for Intersystem Communication.