[systemd-devel] Systemd license vs. libcryptsetup license

[Zbigniew Jędrzejewski-Szmek]

On Thu, Jun 08, 2017 at 09:40:17AM +0200, Krzysztof Jackiewicz wrote:
> > No, that makes no sense. It'd mean that putting two zip files that one provides
> > and the other uses a function with the same name next to one another would
> > make them somehow connected and derivatives of one another. The whole
> > point of dynamic linking is that you can provide independent implementations
> > of the API, and you can clearly substitute libcryptsetup with another
> > implementation, and both bodies of code are usable without one another.
> 
> Then how would you interpret the following statements:
> https://www.gnu.org/licenses/gpl-faq.html#GPLStaticVsDynamic
> https://www.gnu.org/licenses/gpl-faq.html#IfLibraryIsGPL
> https://www.gnu.org/licenses/gpl-faq.html#MereAggregation

I interpret them as FSF wanting to drum up the importance of GPL a bit
by purposefully not clarifying this area. The case of linking non-GPL
software with GPL libraries is quite common and important, and if they
wanted to add an entry to the FAQ, they certainly would. They talk a lot
about "plugins", but that's a significantly different case, because a
plugin is very closely tied to the program that loads it.

> IMHO it's not so obvious and it may depend on a specific
> case. Perhaps in case of runtime dynamic linking when GPL library
> existence is not required for the application to run it will be
> treated as a mere aggregation. With all due respect I think that to
> solve it we'd need a lawyer indeed :)

Well, will all respect due to (a) lawyer, to solve it once and for
all, we'd probably need a body of binding court decisions in multiple
jurisdictions ;)

In the GPL there's very little about what derived means. Various
interpretations in the FSF FAQ are post-factum, and not part of the
license. I'm pretty sure that the interpretation that independent
works distributed as parts of a distro are still independent is in
agreement with both the spirit and the letter of the GPL.
In Galoob v. Nintendo, in appeal, it was ruled that the derivative
work "must incorporate a portion of the copyrighted work in some form",
which does not happen when you just put two rpms side by side.

Zbyszek