Re: how do I fcc: a nnml folder? and what is gcc? (gnus 5.3)

[Raja R Harinath <harinath@cs.umn.edu>]

Steven L Baur <steve@miranova.com> writes:
> >>>>> "Randal" == Randal L Schwartz <merlyn@stonehenge.com> writes:
> 
> Randal> But now I'm stuck.  What's the right Fcc setup to trigger
> Randal> saving into nnml "groups" called "nnml:outbox" or "nnml:todo"
> Randal> or whatever?  The docs say that message-fcc-handler-function
> Randal> is rmail-output by default, but I can't figure out what nnml
> Randal> function corresponds to rmail-output.
> 
> You mentioned using procmail, the magic secret with Gnus procmail
> support is that you do not have to use procmail with it ...
> 
> What I do is let Gnus process Fcc's as if they were incoming
> messages.  Put a line like:
> Fcc: ~/spool/sent.spool
> 
> or whatever folder you wish, in your headers.  The copy gets saved in
> the incoming procmail spool directory.  The next time you M-2 g or g
> to incorporate incoming mail, it will get put into the appropriate
> nnml group.  The problem with doing a direct rcvstore is that it only
> updates the mh unseen file, and you need to keep the .overview updated
> with nnml, and I find it easiest to let Gnus do it.

It's useful, but not safe.  

Mail spool files _should not_ be accessed arbitrarily, since you have
the danger of corrupting them, and of losing mail.

Spool files in the procmail spool directory should recieve the same
careful handling given to, say, `/usr/spool/mail/$LOGNAME'.  They should
be accessed only when you can lock them in such a way that other
"competing" programs (i.e. procmail) cannot/do not try to access the
spool file simultaneously.  Spool files should be accessed only in
mutex.  (Note that this is why Gnus has special procmail support.)

Procmail and movemail use advisory locks on spool files, for mutual
exclusion.  These locks are useful only when all programs involved
recognize them.

You can craft a lock aware `message-fcc-handler-function', that uses the
lockfile(1) program that comes with procmail (Also, such a handler
function won't cause harm on non spool folders either.)  Only then is it
safe to Fcc: to a mail spool.

Thanks for the idea, however.  I occasionally have wanted to use Gcc:
support without loading the whole of `gnus'.  This idea of Fcc:ing to
the procmail spool is an alternative.

- Hari

-- 
Raja R Harinath ------------------------------ harinath@cs.umn.edu
"When all else fails, read the instructions."      -- Cahn's Axiom
"Our policy is, when in doubt, do the right thing."   -- Roy L Ash