called by a process filter?

[Kevin Rodgers <ihs_4664@yahoo.com>]

Is there a way to tell whether a function was called via process filter?

I have a function that is installed on after-change-functions, and which
tries to detect whether the change that triggered it is a user-invoked
character insertion and thus of interest.  But if the change was done by
a process filter (in particular gnuserv-process-filter -> gnuserv-eval),
examining this-command, last-command-event, and/or the result of
(this-command-keys) is completely unreliable because the process filter
runs independently of the command loop.

It might be nice if Emacs temporarily bound all the command loop info
variables to nil while it runs the process filters.  But since it
doesn't seem to, how can I detect that situation?

Thanks,
-- 
Kevin Rodgers