z/OS MVS Programming: Sysplex Services Guide
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Create note pad

z/OS MVS Programming: Sysplex Services Guide
SA23-1400-00

Issue a create note pad request to create a note pad. An answer area is optional. If an answer area is provided, it must be large enough to allow a note pad data record to be stored.

The create request is rejected if the note pad already exists. Otherwise, the XCF Note Pad Services read the CFRM Policy to determine the set of coupling facility structures that are candidates for hosting the note pad. The duplexing attributes and current duplex state of the candidate structures are extracted from the policy. These attributes are then used to sort the candidate structures so that the structures will be examined in an order that honors the structure duplexing preference specified by the create note pad request. The structures are then examined in turn until one is found with enough space for a note pad with the requested number of notes. The duplexing preference of the creator might not be satisfied if none of the preferred structures have space for the note pad, or if none of the structures have the desired duplexing attributes.

To successfully create the note pad, an entry must be added to the XCF note pad catalog, the note pad itself must be initialized in the host structure, and the catalog must be updated to indicate that the note pad is ready for use. In general, the XCF Note Pad Services successfully perform these operations and the note pad is functional upon return from the create request.

However, the host structure or the catalog might become inaccessible after the note pad is entered in the catalog. In such cases, the note pad is defined but not yet functional because the create is incomplete. The terms logically created, being created, and create pending are used to refer to a note pad in this state. Regardless, the create note pad request returns with a return code indicating success and your program can proceed to create connections to the note pad. XCF automatically finishes the create of the note pad when it becomes possible to do so. In some cases, XCF might later discover that the create of the note pad cannot be completed. If so, XCF fails the note pad.

If the create request completes successfully, a note pad data record is stored in the answer area if one is provided. Most of the information in the note pad data record reflects the parameters and options specified on the create request. However, the note pad data record also includes the timestamp of when the note pad was created. Your program might later need this timestamp when it deletes the note pad. The data record also includes a flag to indicate whether the note pad is still in the midst of being created or whether the create is complete.

If an answer area is not provided with the create note pad request, a query note pad request can be issued with an answer area at a later time to obtain the information. However, in cases where you need the timestamp of when the note pad was created, the data reported by this future query will be for the note pad instance that exists at that point in time. It might not be the same instance of the note pad that you created.

As a result of the create note pad request, XCF might issues messages. By default, these messages are written to the hard copy log.

  • Message IXC472I is issued when a note pad is created. If the create is pending, there could be two instances of the message. The first instance indicates that the note pad is in the midst of being created. The second instance is issued when creation of the note pad is completed. Whichever system in the sysplex happens to finish the pending create issues the message to indicate that the note pad is created and ready for use.
  • If the note pad cannot be created in response to a valid create note pad request, message IXC471I is issued to explain why. In general, this message is issued when the create note pad request is rejected due to an environmental problem. It is not typically issued when the request is rejected due to programming errors.

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