Compiling on Windows, and a question of policy

Vernon Schryver
Tue Dec 3 01:04:53 UTC 2002

> From: Paul Wright <>

> ...
> To undo the pollution, I commented out the broken definitions at the
> bottom of /usr/include/cygwin/in.h. dccproc then builds and successfully
> talks to the public DCC servers under Windows.

Congratulations.  I hope the resulting .exe file or whatever can be
spliced into SpamPal somehow.

There are some maintenance issues.  Because Cygwin is entangled with
the GPL, I dare have little to do with it, lest the FSF make claims
on the DCC.  That probably forecloses the obvious possibility of my
including a Cygwin version of dccproc with the DCC source.

Perhaps you could talk James Farmer into tracking DCC changes.

Note that the DCC client code must be able change to deal with
efforts by spammers to evade the checksums.

> ...
> > think recent talk in from those who should
> > know puts the SPEWS DNS load at 250 ops/second.
> Joe Jared seems to think it's about 2500 queries/s:
> <>
> Typo?

I recalled 25-something.  The other day I was trying to remember and
found the URL from that article but not the article.
That URL of suggests an
average of around 200 operations/second.
2500/day makes sense if you assume 10 times as many queries to local
copies and other servers.  2500/day implies about 216,000,000/day
which I suspect is 5-10% of all email on the Internet.  (500 M users
each receiving a handful of messages/day is a few B msgs/day.  Some
of us get zillions, but most people get few per day.)

> ...
> > But don't you need to ask first?
> Yes, which is what I'm doing, in a roundabout sort of way :-) John Payne
> seems to say that he'd take up some extra load. However, if you feel
> strongly that I shouldn't, I won't go ahead and do it (even assuming
> it's possible. 

There are several relevant questions, only some of which I feel strongly
about.  I do not feel strongly about the proximate issue.  I think
wiring dccproc to SpamPal is ok, given my guess of SpamPal's likely
installed base.  If my guess turns out to be wrong, we can adjust the
population of public servers.  Individual public servers shed excessive
load automagically by becoming slower than other servers.  They can
also be adjusted with `dccd -u`.

My view of selling a service based on the is
something else.  It's ok to sell free source; it's not ok to
sell other people's continuing work, bandwith, or CPU cycles.

I think that the several outfits that are selling sevices that use
DCC checksums and their own DCC servers are ok.  They're using my code
for free, but if you believe in free source as I do, that's fine.
They're using the checksums from the global network including the
public servers, but are contributing at least as many checksums as
they are receiving, and so that's also fine.

>                I've not looked at the equivalent of pipes under Windows
> yet, which is what it'd take to meet the Cygwin GPL).

What do you mean?  If it's relevant, as long as I'm involved, DCC
source is unlikely to have a GPL instead of BSD style license.

> ...
> I suspect that people using Spampal are probably the "power users",
> since it requires a bit of fiddling with dialog boxes to set it up.
> ...

Which is another way of saying several comforting things about a
SpamPal+dccproc package:
  - it would not need lots of documentation.
  - it is unlikely to be so wildly popular that it crashes the public
     DCC servers.

Vernon Schryver

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