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Re: hmmm possible gpl problem?
Adrian Prantl wrote:
>>okay - i dont claim to know anything much about gpl ...
>>but - http://www.tux.org/pub/security/secnet/tools/nat10/
>>(which is the only place I found it in a quick google search)
>>distributes a gpl program linked against cygwin.dll (note not cygwin1.dll)
>>without cygwin source.
>>Going on past emails, this looks faulty, but thought i would post it here
>>someone with more experience in such matters to comment.
Nope, it's okay. If cygwin were licensed under the pure GPL, then you
would be correct. However, the cygwin license, in accordance with
section 10 of the GPL, has an exception: if you don't distribute
cygwin1.dll itself, then you needn't distribute the sources to
cygwin1.dll (even if your binary -- which you DO distribute -- is linked
with libcygwin.a[the import lib for cygwin1.dll]). However, in that
case, you're still required to distribute the sources(*) of YOUR program
if you distribute its cygwin-linked binary -- even though, without
cygwin1.dll, the program is inoperable.
(*) further requirement: you must release your sources under a license
compatible with the Open Source Definition:
http://www.opensource.org/osd.html and not just any old "look but don't
> I really don't think that it would be appropriate to start a fox hunt
> everyone that could be violating the gpl in this or the other minor way.
Granted -- we all have better things to do. I think this message, and
the recent vcdimager/etc thread, were both just something people
stumbled onto in the course of other activities.
In the case of the vcdimager issue recently discussed on this list, I
was downloading it *because I wanted to used it*, and when I installed
it, it didn't work: cygwin DLL conflicts. This clued me that the
program (a) used cygwin [Cool!!] and (b) distributed cygwin1.dll
[conflicted with my "real" cygwin installation; not cool.] I was able
to work around (b). However, because I know that if the GPL is not
enforced, then a bad actor could point to all those instances of
non-enforcement, and use that to invalidate the GPL everywhere. ["bad
actor" == NOT another opensource group, but someone who wanted to take
GPL code, modify it, and then distribute the result without source.
"Embrace and Extend"? Microsoft's Kerberos implementation?]. The claim
would go something like this:
"Hey, why pick on me? Obviously the GPL is not enforceable because
you guys didn't enforce it in these other cases. Trying to enforce it
on me is unequal application; you're in violation of the 14th amendment,
It's an illegal restraint of trade, blah blah blah..."
> As long as the reason is not a commercial exploit, I believe that too
> cautions would result in a harm to the free software community. I
> believe that
> a too strict prosecution of the rules would not encourage people to
> there works to the public.
You're welcome to your beliefs. However, the legal realm has its own
rules, which are not subject to your opinions. (sorry, but that's the
blunt truth). Being nice to "the good guys" could cost us big when we
have to fight "the bad guys".
> btw I think the GPL only states that the sources should be made
> available if
> someone asks for them, so it would be ok to distribute the program in
> form and send the source per email if requested. (please correct me if I
Technically, the sources must be distributed "in the same manner as the
binary" -- or a **WRITTEN** offer of source must be provided WITH the
binary. "Written" in legal terms means "on a physical piece of paper".
Since we haven't gotten the Trek transporter technology to work yet,
we can't include this "written" offer inside an electronic download
(that is, a README file doesn't cut it). So, if the binary is on an ftp
site, we must provide the sources on that ftp site. http downloaded
binary? then source must be downloadable via http. emailed binary?
emailed source. binary on CD? sources on CD(*).
(*)Special case (as documented in the GPL): the distributor may charge a
nominal additional fee for the sources to cover the physical duplication
and mailing costs, when the source is provided on a physical medium.
Oh goodie. Another GPL war. I just love these. </end sarc> Sigh.
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