GPLv2 to v3 upgrade and "further restrictions" issue

[Janez Pers]

Roberto Gordo Saez wrote:

> The program that has the additional restriction is linuxsampler
> ( http://linuxsampler.org/ ). I already asked to the authors, replied:

I would advise you that you stay away. Given the authors quite
definitive interpretation and aggressive stance on free software:

http://www.linuxsampler.org/faq.html#commercial_products

he will probably go after you if you strip the commercial
clause out of his license.

Nevertheless, I think that while he is totally right about
the software being free software (this is a vague term)
he is absolutely wrong to use GPL as the license. In fact,
I think that he is even violating the GPL terms by linking
his software against GPLed libraries. GPL is "virulent"
in the sense that you cannot limit derived work further
than original license allows.

See here:

http://www.linuxsampler.org/downloads.html

 From the tone of FAQ it is a bit obvious that people pointed
out this to him already, albeit (obviously) unsuccessfully.

So, the original suggestion stays: I would not dive into
this. If it is for your own use, modify the code as you
wish, but any redistribution will probably put you at odds
with the author.

But obviously (in general) this is thorny issue: people who
use GPL, but restrict it in the various ways. His justification
to limit commercial use is (in theory) covered by GPL terms
themselves (e.g. anyone who would comercially distribute
the software would need to do it source code as well, so
there is no big commercial advantage if GPL terms are
respected).