Library /sys$common/syshlp/nclhelp.hlb loop, loopback_application, name  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Name is the fullname of the node to which loopback messages are
    sent. Specify either this argument or the Address argument, but
    not both.   Optional arguments are: format, length, count.

    loop [node node-id] loopback application  -
         name full-name [,optional arguments...]

    Examples:

    loop loopback application name DEC:.SCH.LAMCHP

    loop loopback application name LOCAL:.LAMCHP, length 80