VMS Help V73 Features, Programming Features, OpenVMS Registry  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Beginning in OpenVMS Version 7.3, the $REGISTRY system service
    and the OpenVMS Registry server have been enhanced to use the
    Intra-Cluster Communications (ICC) protocol. ICC provides a
    high-performance communication mechanism that is ideal for large
    transfers. Using ICC eases restrictions on the amount of data
    that can be transferred between the $REGISTRY system service
    and the Registry server. These restrictions previously prevented
    large key values from being stored and retrieved, and prevented
    full searches of large databases. The changes made in OpenVMS
    Version 7.3 result in an incompatibility between the OpenVMS
    Version 7.2 $REGISTRY service and Registry server and the OpenVMS
    Version 7.3 $REGISTRY service and Registry server. However, these
    changes substantially benefit OpenVMS customers in this release
    and in future releases, when we plan to further reduce these
    restrictions.

    Also in OpenVMS Version 7.3, registry operations are
    client/server based, and as such require some length of time
    for the server to respond to a request. If the server is too
    busy or the timeout value is too small, or both, the server
    will not respond in time and the $REGISTRY service will return
    a REG$_NORESPONSE error. This does not necessarily mean that
    the operation failed; it only means that the server was not able
    to respond before the time expired. Most operations complete
    immediately. However, Compaq recommends that you specify the
    timeout value be a minimum of 5 seconds.

    The new format of the $registry system service is:

    $REGISTRY [efn], func, [ntcredentials], itmlst, [iosb] [,astadr]
    [,astprm] [,timeout]

    Note that astadr, astprm and timeout are optional arguments.
    These optional arguments cannot be defaulted, which means that to
    specify the timeout argument, you must specify astadr and astprm
    (or specify them as 0). Some languages, such as Bliss and Macro,
    provide macros to do this for you.

  Additional Information (explode) :

• REG$CP Registry Utility