generate nov data from the command line

[Harry Putnam <reader@newsguy.com>]

I asked this question a while back, on gnu.emacs.gnus but never got
any suggestions.  Here is my delima:

I set up a couple of extra nnml servers a while back and have been
rsyncing my agent downloads into that hierarchy.  It accumulates lots
of files, thousands of them.  The nnml server handles them well,
getting the groups and etc has all worked nicely.   

The problem comes from the way I'm putting the new messages in behind
gnus back.  Since there is no fast way to do that job with gnus, I'm
doing it with `rsync' then generating the nov data with:

nnml-generate-nov-databases  by pressing 'g' on the proper server in
trhe server buffer.   

This can  be time consuming  with this many  files, but wouldn't  be a
problem with cron or just in the backgroud while I do other stuff.

I had visions of coming up with a batch command that could be called
by an rsync wrapper script.  So when rsync is finished, gnus is
called in to straighten out the stealth attack.  And make crispy new
nov data.  All this at 2:30am.

I see how to call functions in batchmode with the -f flag and  how
to load files etc, but this is a bit more complicated I think.  How
can I tell gnus which server to use?  These are not the default ones.

The line below seems to work on the default nnml server but how
to evaluate something to set a different one ... on the command line.

emacs  -batch -l .emacs -l .gnus -f nnml-generate-nov-databases

Two major archives are involved:

330MB and 418MB and  114898 files
Gnus can do this in less than 15 minutes, I've never timed it but it's
well under 15, but still not something you'd want to wait for.