Library /sys$common/syshlp/latcp$help.hlb DEFINE, /KEY, Qualifiers, /SET_STATE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /SET_STATE=state-name

    Causes the specified state to be set when you press the defined
    key. The state name can be any alphanumeric string (for example,
    GOLD). Use the DEFINE/KEY/IF_STATE=state-name command to
    associate new meanings for keys when the specified state is set.
    See the example for the DEFINE/KEY command.

    If you omit the /SET_STATE qualifier, the current state that was
    locked remains in effect.