Creates an instance of the modem connect line entity.  This
    modem connect line entity is associated with a physical circuit on
    the node.  Usually, there is one line entity for each circuit.
    Line-name is a simplename that identifies this modem connect line
    instance.

    create  [node node-id] modem connect line line-name -
             communication port port-name [,optional arguments...]

    The required Communications Port argument specifies the name of
    the communications port to which the communications line is
    connected.

    The optional arguments for the create modem connect line command
    are:  communications mode, duplex, connection type (Tru64 UNIX),
    profile, and rate select (OpenVMS).

    Examples:

    create modem connect line DSY-0-0 -
         communication port DSY-0-0

    create modem connect line DDCMP-0 -
         communication port DMB-0-0, -
         communications mode synchronous, duplex full

    create modem connect line dsv-0 -
         communication port DSV-0-0, -
         profile "NORMAL"