dynamic mail alias lists?

[Doug Lee]

Is there a way to make sendmail (or any other MTA for that matter, but
I use sendmail) map an alias to the run of a process that returns the
addresses for it?  I know /etc/[mail/]aliases can forward through a
program, but that's different.  I also know it can read aliases from a
file, but to use that for this, I'd have to make the file a named
pipe.  Named pipes are interesting, but I like to avoid them unless
necessary because accidents can cause infinite program stalls.
Finally, I know some of sendmail's tables (virtual user??) can be used
in place of or in addition to aliases, but I still don't see a way to
use that for this.

What I want to do is to make some of my aliases retrieve their address
lists at run time from a database of my own design that also may be
used for other things.  Example:  A database of users in different
categories, where there are mail aliases for the categories and a way
to get the users in a particular category at run time from the
database.

Please let me know if this is possible--or, for that matter, if I'm
missing an obvious and less bizarre solution.

Please Cc me on all responses.  I subscribe to this list, but a Cc
will get me to notice the reply in hours instead of days or weeks. :)


-- 
Doug Lee           dgl at dlee.org        http://www.dlee.org
Bartimaeus Group   doug at bartsite.com   http://www.bartsite.com
"It is difficult to produce a television documentary that is both
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