Library /sys$common/syshlp/ncphelp.hlb SET, LINE, STATE line-state  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Specifies the line's operational state.  There are three possible line
 states:

    OFF       The line is not in use.

    ON        The line is available for normal use.

    SERVICE   The line is available only for service functions.