[Mimedefang] Adding support for learning our addresses

[Philip Prindeville]

David F. Skoll wrote:

>Neophytes shouldn't attempt to use MIMEDefang.  Anything that pretends
>to make MIMEDefang usable by neophytes is a bug, not a feature, IMO. :-)
>  
>

Well, you can know something about email, even Perl scripting, and not know
of a better way to get IP addresses than grepping out "ifconfig -a" ...

>>(2) you can run the same config on a cluster of servers unmodified;
>>    
>>
>
>On a server whos IP address does not change, you can extract it in
>filter_initialize.  It's only invoked once per slave, so the performance
>overhead is negligible.
>  
>

We're talking crossed purposes.  I'm saying that embedding the address 
explicitly
into the config means that you can't have an identical config running on 
a pool
of mail servers.

You're saying that the overhead of determining the address once at 
startup is
acceptable.

Both are true, but unrelated.

>>(3) mobile users with dynDNS can use it.
>>    
>>
>
>Users on dynDNS are likely doing so little e-mail traffice that the
>performance hit of running ifconfig per message isn't an issue.
>  
>

Probably, but it's still a cooler way of figuring it out.  ;-)

-Philip