[sane-devel] Please give me some help to solve the license issues in using sane

m. allan noah kitno455 at gmail.com
Fri Jun 6 14:26:04 UTC 2008

On 6/6/08, Alessandro Zummo <azummo-lists at towertech.it> wrote:
> On Fri, 6 Jun 2008 09:54:13 -0400
>  "m. allan noah" <kitno455 at gm
> >
>  > gpl faq is pretty clear on this one:
>  >
>  > If the modules are included in the same executable file, they are
>  > definitely combined in one program. If modules are designed to run
>  > linked together in a shared address space, that almost surely means
>  > combining them into one program.
>  Ok, but where it is saying that a GPL app cannot use a non GPL
>   library?
>   I think the faq has been written from the point of view
>   of someone who tries to use a GPL library in a closed
>   source program.
>   Here we have a GPL app that may be using a closed source
>   library. Unless the license of the library forbids that,
>   it should be fine, right?

no, the GPL is all about derivative works and combining code, it makes
no difference the direction:

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.

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




<I'd like to incorporate GPL-covered software in my proprietary
system. Can I do this by putting a "wrapper" module, under a
GPL-compatible lax permissive license (such as the X11 license) in
between the GPL-covered part and the proprietary part?>

    No. The X11 license is compatible with the GPL, so you can add a
module to the GPL-covered program and put it under the X11 license.
But if you were to incorporate them both in a larger program, that
whole would include the GPL-covered part, so it would have to be
licensed as a whole under the GNU GPL.

    The fact that proprietary module A communicates with GPL-covered
module C only through X11-licensed module B is legally irrelevant;
what matters is the fact that module C is included in the whole.



You'll notice that both of these quotes hinge on the definition of
'incorporation', which the GPL seems to define primarily as running
under the same PID, with no matter which part (the program or the
library) is the GPL part.

"The truth is an offense, but not a sin"

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