From: Russ Allbery (rra@stanford.edu)
Date: Mon Sep 04 2000 - 18:22:45 CDT
Charles Lindsey <chl@clw.cs.man.ac.uk> writes:
> Russ Allbery <rra@stanford.edu> writes:
>> and just use the colon as part of the value since it doesn't change.
>> If whitespace is allowed around the equal sign, that can be dealt with
>> although it's annoying. Comments are right out. If we're going to
>> allow spaces in posting-host, then it should *always* be quoted so that
>> the parse can be easy; sometimes quoted and sometimes not quoted is
>> much more annoying to deal with.
> The whitespace and comments are there because they are there in all our
> headers (except Newsgroups and Path, which we singled out).
Right, I know, but it makes the header much more difficult to parse. If
you want to replace something that's working quite well for the majority
of people, you need to make it *really* easy to use the new thing.
> Indeed, comments regularly appear in X-Trace.
Practically no one filters on X-Trace; the only use X-Trace really has
right now is to provide information to the originating site. Everyone
filters on NNTP-Posting-Host because it's considerably easier and most
sites that generate X-Trace also generate NNTP-Posting-Host. Besides, the
comments in X-Trace for *most* servers are reliably always in the same
place (and the fact that they aren't that way everywhere is a big part of
the reason why no one filters on X-Trace).
> The alternative is to pass the whole header through an
> "unfolding/de-commenting" process before trying to parse it. This is
> probably a useful tool to haver available for other headers, too.
Yes, but you're putting more programming onto the filter writers and
they're under no obligation to pay any attention to our weird new headers
at all. Unless it's easy to use, I don't think anyone's going to use it.
> I was trying to have a very specific syntax for each parameter (see my
> reply to Clive). So "identity" would be a different header with a
> different syntax. Remember that all these headers are optional, so the
> injector includes just those which it considers appropriate to its
> situation.
That's going to make it basically worthless for spam filtering, then, and
everyone's going to just keep using NNTP-Posting-Host. I know I would.
To do spam filtering, you need something that's pretty much reliably
always there and always means roughly the same thing. NNTP-Posting-Host
right now achieves that about as well as you ever will on Usenet, at the
90-95% level. If the proposed replacement isn't as good as that, most
people are going to just ignore it.
-- Russ Allbery (rra@stanford.edu) <http://www.eyrie.org/~eagle/>