GUI goodness for your Mouse and Keyboard programming

Gilles Gravier gilles at
Wed Oct 1 08:58:10 UTC 2008


EOD? That's a bit unilateral, for somebody posting on a mailing list...

Heike C. Zimmerer wrote:
> Gilles Gravier <gilles at> writes:
>>> Note that they mention the GPL (not the LGPL).  Such a combination is
>>> clearly illegal - you would need the libs to be LGPL'ed to allow closed
>>> source to be linked against them.  
>> No. You are wrong. The fact that they link to doesn't mean that they
>> have to be GPL.
> It does.  Read the FSF's "GPL FAQ" where it is explicitly discussed and
> compare the GPL to the LGPL which has been made specifically for these
> cases (linking against proprietary code) and would be probably not
> needed if this distinction weren't in effect.  
I have read it.
> It doesn't matter how the program is bundled and where the GPLed part
> comes from
Oh yes it does.

- Prelinking, for example, doesn't introduce license requirements (see for details)

- Aggregation, also... as discussed here : is a complex
subject, depending on how the aggreagation is done. They cite the
example of distributing on a CD-ROM. But they don't mention downloading
separate modules. They do talk about how modules interface... and cleary
explain that "This is a legal question, which ultimately judges will
decide." ... there are many ways of having modules interface. Not all
are clearly identified as having licensing implications.

>  - if you don't want to conform to the GPLs licensing terms,
> there's always a simple way: don't write a program which uses GPLed
> parts, e.g. by letting your program link (dynamically or statically)
> against them.  After all, that's the situation you find elsewhere where
> proprietary code is prevalent, so stick with it if you want to do the
> same.  You can't just pick the best from both sides and disregard the
> rest.
Yes you can. That's why the GPL was written. It just tells you how you
can go about doing it, what the implications are, so that you can do it
in the way that works with your own business model.

The details are at the (I'd
like to incorporate GPL-covered software in my proprietary system. Can I
do this?) section. Just so that you don't have to do the work, here's
the text, quoted.

You cannot incorporate GPL-covered software in a proprietary system. The
goal of the GPL is to grant everyone the freedom to copy, redistribute,
understand, and modify a program. If you could incorporate GPL-covered
software into a non-free system, it would have the effect of making the
GPL-covered software non-free too.

A system incorporating a GPL-covered program is an extended version of
that program. The GPL says that any extended version of the program must
be released under the GPL if it is released at all. This is for two
reasons: to make sure that users who get the software get the freedom
they should have, and to encourage people to give back improvements that
they make.

<************* NOTE THIS IMPORTANT PART *************>
However, in many cases you can distribute the GPL-covered software
alongside your proprietary system. To do this validly, you must make
sure that the free and non-free programs communicate at arms length,
that they are not combined in a way that would make them effectively a
single program.
</************* NOTE THIS IMPORTANT PART *************>

The difference between this and “incorporating” the GPL-covered software
is partly a matter of substance and partly form. The substantive part is
this: if the two programs are combined so that they become effectively
two parts of one program, then you can't treat them as two separate
programs. So the GPL has to cover the whole thing.

<************* NOTE THIS IMPORTANT PART *************>
If the two programs remain well separated, like the compiler and the
kernel, or like an editor and a shell, then you can treat them as two
separate programs—but you have to do it properly. The issue is simply
one of form: how you describe what you are doing. Why do we care about
this? Because we want to make sure the users clearly understand the free
status of the GPL-covered software in the collection.

If people were to distribute GPL-covered software calling it “part of” a
system that users know is partly proprietary, users might be uncertain
of their rights regarding the GPL-covered software. But if they know
that what they have received is a free program plus another program,
side by side, their rights will be clear.
</************* NOTE THIS IMPORTANT PART *************>

Is that clearer?
> (This applies to linking against a GPLed library.  Of course, this
> doesn't apply to other programs you may be running on a GNU/Linux box).
> That's all I have to say, EOD from my side
Thanks.... end of discussion, you say?


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