(unknown)

The documentation for CAPI:OUTPUT-PANE in the CAPI Reference Manual
describes how to identify gestures and associate them with callback
functions for the :INPUT-MODEL initarg of the pane.

We're using LispWOrks to develop and deliver an application which runs
on the Macintosh.  I need to be able to distinguish mouse clicks which
have been modified by the "option" or "command" keys from plain clicks
and those modified with "shift" or "control".

The documentation describes how to name control-click and shift-click

    (:button-1 :press :shift)
    (:button-1 :press :control)

but does not describe how to name mouse gestures which include the
other modifier keys.

When I tried to take a stab in the dark and add an entry for
(:button-1 :press :command) then the callbacks are called as if every
gesture was (:button-1 :press :command).  This is also the case if I
use :OPTION in the gesture name instead of :command.

It's one thing to not document or not support certan modifier keys.  I
have no clue how the implementation could be invoking callbacks for
gestures it does not support to the exclusion of all others though.