[cairo] Re: License for cairo changed to LGPL

James Henstridge james at jamesh.id.au
Tue Aug 3 21:29:06 PDT 2004

On 04/08/04 09:54, M. Evans wrote:

> Carl,
> Not even the GPL itself prevents
> forking. I do not see how an open
> source license prevents forking.
> GNOME recently forked.

The difference between the Goneme/Gnome fork and the type Carl mentioned 
is that the license ensures that fixes can continue to flow in both 
directions after the fork.  With a proprietary fork, fixes can flow in 
one direction (free -> proprietary), but fixes won't necessarily go in 
the other direction.

> Anyway, I am also an embedded developer.
> I do see a big problem with LGPL in this
> domain.  Generally source code release
> is not something a developer decides.

Remember that the LGPL does not mean that you need to release the source 
of your main program.  You are only required to distribute or make 
available the libcairo source code plus any modifications you make to 
the library itself.

If your device has upgradeable firmware (as many do these days), and 
Cairo exists as a shared library in the firmware image then that covers 
most of the requirements of the LGPL (of course, you should get a 
lawyer's opinion on this rather than taking my word for it).

> That big-think percolates right up the
> management chain, and if management says
> "no," that pretty much kills the choice
> off.  It doesn't matter if the engineer
> is willing and able to be very, very
> clever about releasing his source code.
> It's just not his call. That has been my
> experience.

Surely the other software you use has license conditions attached?  Sure 
the LGPL terms are a bit different, but don't seem that bad.

> Now of course some changes
> are always required to get any code
> functional on embedded systems, because
> each one is so unique.  I do not think
> it is FUD to raise these issues.
> They are quite valid.

Is there any reason why you would want to keep these sort of compilation 
fixes private?  By submitting them upstream, you won't have to port the 
patches forward when new versions of Cairo are released.  This should 
reduce the work you need to do in the long run, and make Cairo better.

> In fact three GUI toolkits use LGPL
> with special binary linkage exception
> clauses. R. Stallman has reviewed and
> OK'd the wxWindows version.  These
> licenses were developed after lots of
> debate, hashing, etc., over years.
> Here are the links. Read and enjoy.
> Cairo might consider something close.
> http://www.wxwindows.org/newlicen.htm
> http://www.fltk.org/faq.php?3
> http://www.fox-toolkit.org/license.html
> Thank you for Cairo, under any license!

It seems like the wxWindows exceptions are at odds with Carl's desire to 
prevent proprietary forks.  It seems to say that they can create such a 
fork provided they don't share their source code modifications with any 
other entity.


Email: james at jamesh.id.au
WWW:   http://www.jamesh.id.au/

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