We've got a couple of large mailing lists that we want to manipulate in
various ways.  Originally I was thinking that this would be best done with
topics, but I couldn't think of a way to send mail to subscribers who were
subscribed to one topic but not another (that is, leaving out subscribers
in the intersection).

I have an idea of how to do things, but I wanted to check and see if anyone
had any ideas for a better way to do it.  Some things seem to be tricky to
do, and I don't want to make things more difficult than they have to be.

The setup I envision:
======================
Master mailing list BULK-L [or whatever] with sublists DEV-COM and
JAVASCRIPTS-COM.  DEV-COM has about 75,000 subscribers and JAVASCRIPTS-COM
has about 140,000.

To send a message to everyone on both mailing lists:
----------------------------------------------------
Send mail to BULK-L.  No duplicates will go out.

To send a message to one mailing list or the other:
---------------------------------------------------
Send it to the appropriate mailing list (DEV-COM or JAVASCRIPTS-COM).

To send a message to all subscribers of one mailing list who are not
subscribers of the other:
-------------------------
Say you want to send a message to all JAVASCRIPTS-COM subscribers who are
not DEV-COM subscribers, use the following method.

Get a list of DEV-COM subscribers (the REVIEW command gives you this).

Issue a Q JAVASCRIPTS-COM WITH NOMAIL FOR *@* to get a list of sub-jav-com
subscribers currently set to nomail.

Using a modification of a perl script already created, do a QUIET SET
JAVASCRIPTS-COM NOMAIL for all DEV-COM subscribers.

Send out the mailing, then issue a QUIET SET JAVASCRIPTS-COM MAIL FOR *@*.

Set those who were originally set to nomail back to nomail.
======================

Thanks,
Jacob Haller
LISTSERV Admin
EarthWeb Inc.