[Mimedefang] Adding support for learning our addresses

[Philip Prindeville]

Damrose, Mark wrote:

>That wouldn't work on my system, and many others.  If you do a
>gethostbyname() you'll get the local unroutable address back - 
>since the internal and external DNS for my namespace are maintained
>on separate servers.
>  
>

Not if you query one of the root name servers...

>If you are using NAT, then in order to accept mail to 
>postmaster@[ip.add.re.ss] (see RFC1123 Section 5.2.17), you'll need 
>to include [ip.add.re.ss] in /etc/mail/local-host-names.  Why not 
>read that file?
>  
>

Gak.  Then we're relying on its format staying the same, and second that
we need to be able to parse the file.

Or we could arrange to export $=R...

-Philip