REG_NAMELIST: Registering Interest in a List of Data Items

You might want to identify a list of data items to the cache structure with one operation. The REG_NAMELIST request allows you to:

Define (allocate directory entries for) up to 32 new data items to the cache structure and register interest in those data items, and
Register or re-register interest in up to 32 currently defined data items in the cache structure.

The REG_NAMELIST request type is valid only for a structure allocated in a coupling facility with CFLEVEL=2 or higher.

As with the READ_DATA request, when you define each new data item, you can specify that the system is to try to allocate and initialize a directory entry for the data item. If the system can allocate the directory entry, the system also registers your interest in the data item and validates your local copy of the data item. If the system is unable to allocate the directory entry because resources are unavailable and cannot be reclaimed, the system will terminate the request, perhaps without having processed all the data items you have specified.

For each data item in which you want to register interest, you build a registration block identifying the data item, its associated local cache vector index, and other information specific to the data item. When processing of the REG_NAMELIST request completes, the system returns status information about each of the data items identified by a registration block. This status information indicates whether the user was successfully registered for the data item.

If successful, the system returns directory information about the entry, and the user's local vector is marked valid.
If not successful, the system does not return directory information about the entry, and the user's local vector is marked invalid.

Guide to the Topic

REG_NAMELIST: Registering Interest in a List of Data Items is divided into two topics.

The first topic, IXLCACHE Functions for REQUEST=REG_NAMELIST, applies to all REG_NAMELIST requests and includes the following major topics:

The second topic, Registering Interest in a List of Data Items: Summary summarizes a procedure for specifying a list of entries to be registered.