On Fri, 2010-06-11 at 09:49 +0200, Jakob Hirsch wrote: > Hm, do you really need the _whole_ body? Otherwise,
> ${sha1:$message_body} would do what you want (hash the first 500 bytes).
> Otherwise I guess you could set message_body_visible to a high enough
> number (like message_size_limit), but I'm not sure how efficient Exim is
> handling such big strings. OTOH, it probably doesn't matter much on
> todays machines, as long as you are not hitting some internal limits
> (which I don't know of). If you care about efficiency, you could use dlfunc.
> Or is this something useful for other Exim users, too?
I would caution against a builtin which is this computationally
intensive, especially in the case of large/very large messages. It will
adversely affect Exim's processor utilisation (by some margin for very
large messages) and greatly increase processing time.
As Jakob says, the tools already exist to do this; better to make use of
them (and perhaps generate a Wiki entry to explain how to do it, and
why) than make Exim generate a hash for every message.
