[spambayes-dev] pop3proxy execution "rules" on Windows

[Mark Hammond]

This is going back to the discussion last week about "per-user" data.  It
really only applies to the "front ends" we will provide for the proxies
running on Windows.

Currently, we provide only a "per user" proxy (ie, the data can not be
reasonably shared among multiple users).  We should make an effort so
"profile roaming" works such that when a user logs on to another machine, if
SpamBayes is installed on that machine, it all just works.  This is already
true for the Outlook addin, and users appreciate it.

This is a particular problem for the service, which by default is installed
to run as the "local system" user.

Without going into the meandering reasoning behind it, I propose the
following:

* pop3proxy etc data is stored in the per-user "{Application
Data}\SpamBayesProxy" (ie, next to the "SpamBayes" directory used by
Outlook.  It could be "SpamBayes\Proxy", but I see no good reason to mix the
data up.  I think we all agreed this (bar the specific name!)

* pop3proxy_service will refuse to start unless it is configured to use a
specific user name.

* The application will create a mutex named somehting like
"SpamBayesProxy-{username}".  If that mutex exists, it refuses to start (as
it must already be running for that user on the machine)

* For the sake of simplicity all round, pop3proxy_normal (ie, the "normal"
executable, whatever it is) will refuse to start if the service is already
running on the current machine, even if it is running as a different user.
If you want one machine to support multiple users concurrently running
pop3proxy, you can't use the service.  I suspect this will not be a problem,
as people who want to run the service will tend to have exclusive access to
the machine.  (Note the tray icon app could still start in this case, which
could control the service - just never a proxy)

Later we can obviously relax any of these restrictions.

Does that make sense?

Mark.