Programming considerations for Exit 6

The following considerations apply to Exit 6:

• When the exit routine is entered, register 13 points to a standard 18-word save area that can be used to save the caller’s registers. Exit 6 might receive control while one of the other exits is active. If Exit 6 needs to make an external call, the code should use ECAMSGSV, a unique save area provided for this exit in the ECA.
• When the exit routine is entered, register 1 points to a one-word parameter list with the address of the parameter area, APSGEXTP. APSGEXTP contains a pointer to the exit-communications area, APSUECA.

  Exit 6 can use the APSUECA work buffer, ECAWKBUF. If this work buffer is too small, see Exit table, APSUCOM for information about expanding ECAWKBUF. If you expand ECAWKBUF, PSF does not use the additional storage (that which exceeds the APSUECA default size) between successive exits. The PSF exits can therefore use this storage to maintain information between successive exits.

  Notes:

  1. The transmission-count field, ECATRNC, is not updated before this exit is called.
  2. ECEOUTTK and ECEJDVT are not updated before this exit is called.
• Use register 12 as a base register for exit routines. If register 12 points to the beginning of the exit routine, and the module name starts at the sixth byte in the routine, the module name appears in the PSF SDUMP, "Symptoms for This Dump," if the routine has an abend. The PSF component name and subcomponent names can also appear on the SDUMP title page.
• XTP6, a dsect in APSGEXTP, contains information that Exit 6 needs to have in order to determine its action. The pointer XTPRECP within APSGEXTP provides the address of XTP6. XTP6 is mapped within macro APSGEXTP. For more information about APSGEXTP, see Figure 76.
• The message action, XTP6ACT, can be changed by the exit in one of these ways:
  • If the exit does not alter XTP6ACT, PSF takes the action that the message originally called for.
  • If the exit sets XTP6ACT to 0, PSF suppresses the message.
  • If the exit sets XTP6ACT to one or more actions, PSF takes those actions.
• The following restrictions apply to XTP6ACT:
  • Action messages, noted by the format APSxxxA or APSxxxxA, cannot be suppressed. If the exit requests that an action message be suppressed, PSF ignores the request and sends the message to the operator.
  • The exit cannot request that a message be printed with the data set, XTP6PAP, unless that was the original destination set by PSF.
  • If the message is suppressed, PSF still traces the message.
  • PSF issues some messages twice, once to the operator and once for printing with the data set. When a message is to be redirected, you might want to code a check for duplicate messages.
• Consider the following restrictions:
  • This exit is entered before the FSA part of PSF issues a message from PSF. The printer runs asynchronously to this exit, and is not affected by its actions. While this exit is running, the FSA part of PSF is not running.

    If any of these messages are issued, processing is not transferred to the exit:

    APS000I  APS005I  APS038I  APS046I  APS051I  APS060I  APS605I  APS957I
    APS001I  APS006I  APS042I  APS047I  APS052I  APS226I  APS608I
    APS002A  APS022I  APS043I  APS048I  APS053I  APS516I  APS610I
    APS003A  APS023I  APS044I  APS049I  APS054I  APS517I  APS922I
    APS004I  APS025I  APS045I  APS050I  APS055I  APS551I  APS955I      

    Processing is not transferred to this exit in any of the following conditions:

    • For any message generated by the APSRMARK utility—messages APS580I to APS599I.
    • For any message generated by the trace formatter utility, APSTRFMT—messages APS960I to APS979I.
    • For any message generated by the APSRFLU utility—messages APS1700I to APS1711I.
    • For any message generated from the Notify Subtask (NST)–messages APS062I to APS068I, APS070I to APS072I, APS075I to APS078I, APS8560I, APS8562I to APS8564I, and APS8566I.
    • For any message generated by the operator interface—messages APS620I through APS699I, with the exception of message APS691I.
  • The error that the message reports is not necessarily related to the data set that PSF is currently processing. The JSPA also provides information about the data set that PSF is processing (not necessarily about the data set to which the message belongs).
  • When this exit is called, the JSPA pointer, XTPJSPAP, might be set to 0.