XES/Notify Exit Communication

Similar to the contention exit, the notify exit receives the current resource request queue as input. The queue is presented in the form of a notify exit parameter list (NEPL), mapped by the macro IXLYNEPL. The NEPL for locking requests has a header that contains information pertaining to the connector and the lock structure along with a lock section that includes the identification of the resource that is in contention. These sections are followed by a series of entries (mapped by NEPLENT) that reflect the interest of other connectors (both owners and waiters) in the specified resource. The NEPL information includes:

• Header section information
  • Connect data, such as the connect token and connect name of the resource owner (NEPLCONTOKEN, NEPLCONNAME)
  • Structure information, such as rebuild status (NEPLREBUILD)
• Lock section
  • Lock data, if any, that was specified when resource ownership was obtained (NEPLLOCKDATA)
  • Resource identifiers, such as resource name, length, and hash value (NEPLRNAME@, NEPLRNAMELEN, NEPLHASHVAL)
  • 32-byte work area, passed from the contention exit (NEPLWORK)

    This work area which is shared between the contention exit and the notify exit. Specifically, when the contention exit requests that the notify exit be executed, the contents of the work area within the corresponding CEPL entry (CEPLEWORK) is passed to the notify exit. The notify exit receives this information by way of the NEPLWORK field. Any changes made to this area by the notify exit are subsequently presented to the contention exit.

  • Ownership data, such as state and user data for this resource owner (NEPLSTATE, NEPLUDATA)
  • An input/output area, which can be used in conjunction with the IXLSYNCH service to update the ownership data (NEPLOUT).
  • A version number of the lock section (NEPLLOCKVERSION)
  • An area used in conjunction with the IXLSYNCH service to provide an asynchronous duplexing request sequence number (NEPL1ADUPREQSEQNUM). Valid only when the lock section version number is at least NeplLockVer1.
• Entry information
  • Requester information, such as version, connection identifier, and connect name (NEPLECONVERSION, NEPLECONID, NEPLECONNAME)
  • Ownership data, such as state and user data, for both the held state and the requested state (NEPLEHELD, NEPLEREQ).