General rules for multiple DPAGE input

Follow these rules for multiple DPAGE input.

  1. If any mapped input LPAGE contains no data segments (as a result of segment routines canceling all segments, for example), the input message is rejected and an error message is sent to the other subsystem.
  2. MFS echo to the input terminal is ignored.
  3. MFS password creation occurs from any DPAGE, but once created, any other password is ignored. If the password is included in the attach FM header, this password is used for DPM-Bn.
  4. Input message options 1, 2, and 3 apply to LPAGEs. If option 2 is requested, null segments at end of an LPAGE are eliminated. This alters the relative positions of the segments in the next LPAGE (if any) in the input message. If option 1 or 2 is requested, the first segment of the second and all subsequent LPAGEs have the page bit (X'40') in the Z2 field turned on regardless of any null segments resulting at the end of the previous LPAGE. If option 3 is requested, the segment ID is equal to 1 for every first segment in the new LPAGE.
  5. Multiple DPAGE input requested in MFS definitions does not restrict message creation from the single DPAGE.
  6. If your control request is entered with the first input DPAGE, the request is processed and the input message is rejected. If your control request is entered with an input DPAGE other than the first, the request is ignored and the input message is accepted.
  7. If your logical page request is entered with the first input DPAGE (that is, an equals sign (=) in the first position of the input segment), the request is processed and the input message is rejected.

If multiple DPAGE input is not requested of MFS definitions, message creation from more than one DPAGE is not permitted and these rules apply:

  1. If a single transmission contains more data than defined for the DPAGE selected, the input message is rejected and an error message is sent to the other subsystem.
  2. If the message has multiple transmissions, the input message is rejected and an error message is sent to the other subsystem.