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Compliance with the GPL (cygwin)

License compliance for programs which use cygwin.
   VCDImager (cygiwin-1.3.6)
   cdrdao    (cygwin-1.1.8)
   VCDEasy-full (BOTH cygwin's, since it includes the above)

I'm ignoring the issue of multiple cygwin versions installed on the same 
system, which may conflict with a "real" cygwin environment on the 
user's computer, and with each other....that's a different topic (and I 
don't know what the "right" solution is, so...skip it)

Here, I'm only concerned with projects that are not complying with the 
GPL license of the cygwin DLL.  Since all of these projects are part of 
the open-source milieu, I know that any infraction of the license of 
another open-source project is unintentional...but violations should be 

Note that it's very easy for each of these projects to comply with 
cygwin's license (the GPL): just
   1) make their own source available (true already, for most of them)
   2) put a tarball of the (appropriate) cygwin DLL source code on
      their ftp site with their other downloads,
   3) ditto for other cygwin-linked libraries (zlib, libxml, libjpeg)
      if applicable
   4) mention the availability of the source code for libraries
      used to create their windows port somewhere on their
      webpage (not strictly necessary, but what's the point of
      1 -- 3 if you don't advertise it?)
   5) A plug for the cygwin project itself (
      would be nice, but definitely not necessary for license compliance.

To dampen the inevitable arguments about the GPL:
If you distribute a binary (such as cygwin1.dll) that is under the GPL, 
then YOU have to also distribute the source code for THAT binary.  You 
cannot just say "get the source over there, at".  If you 
don't believe me, READ the GPL.  READ the commentary on it by RMS. In 
addition, if you link your executable to a GPL'ed shared library (lik 
cygwin1.dll), then you must distribute the source code for your 
executable, as well, or you lose the right to use cygwin1.dll.  It's all 
there in the GPL.

cygwin hacker

VCDEasy includes:

    which contains cygwin1.dll-1.1.8
    cdrdao doesn't distribute the source of cygwin,
      although it is opensource itself.  They DO
      distribute a cygwin-linked "windows" binary
      along with a copy of cygwin1.dll itself
      (but no mention of the cygwin project anywhere)
    BTW: not even cygwin distributes or uses this old
      version anymore.  Fortunately, the VCDImager guys
      went thru the effort of extracting from CVS and
      creating a cygwin-1.1.8 tarball, back when they
      were using that old version.  The cdrdao guys could
      a) get it from them & redistribute it, or b) update
      to a newer cygwin and get the source from us.

    which contains cygwin1.dll-1.3.6 and cygjpeg6b.dll
    Now, the mjpegtools project doesn't seem to provide
      windows binaries; the windows (e.g. cygwin) port
      seems to be something the VCDEasy folks did.

    which contains cygwin1.dll-1.3.6, cygz.dll, and cygxml-2.dll
    VCDImager provides the src for cygwin, but not
      zlib or xml.  (Actually, they provide LOTS of different
      src tarballs -- probably more than they need to -- but
      all for various versions of cygwin, not zlib/xml.

So, to sum up:

   VCDImager project: seems mostly compliant; need a reminder to
   include also OTHER source code (zlib, libxml)

   cdrdao: open source, but not complying with the cygwin GPL.
     they need to distribute the source for:

   mjpeg-tools: they don't distribute cygwin-linked binaries, so
     they are under no obligation to distribute cygwin sources.

   VCDEasy (includes all of the above): provides no source, whatsoever,
     for cygwin, cygwin-linked binaries, cygwin-linked dlls, nothing.
     NADA.  ZILCH.  Totally non-compliant.
   VCDEasy needs to distribute the source for:

Contact info:

cdrdao:       Manuel Clos  at
mjpeg-tools:  (not needed)

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