On May 5, 10:50 pm, William Stein <wst...@gmail.com> wrote:
> On Tue, May 5, 2009 at 3:25 PM, Brian Granger <ellisonbg....@gmail.com> wrote:
<SNIP>
> > * Is the code pure python or does it use the sage syntax? If the code
> > uses the sage syntax, I think it must be released under the GPL.
> > * Does the code being written actually use any GPL libraries (like the
> > sage python package)? If the code uses GPL libraries, I again think
> > it must be GPL'd.
>
> Publicly distributed code using GPL'd library must be GPL'd.
Well, having thought about this for a while I would like to point out
something: The Sage notebook communicates with a Sage python process
via pseudo tty. I.e. once the Sage notebook is spun off and no longer
uses GPLed libraries that are used as extensions the situation in the
FSF's FAQ no longer applies. As long as there is a socket or fork()
between your code and Sage the GPL no longer applies.
Something closely related it a known hole in the GPL, i.e. you can
take GPLed code, modify it, expose it to the user via a webinterface
and the GPL does not apply here since no distribution happens. That is
why we have the Affero general public license. RMS has obviously
bitched about how "software as a service" is taking away out freedom,
but yadda yadda yadda :).
<SNIP>
> > This is relevant, because I need to
> > clarify these issues for students and faculty who would use Sage in
> > this manner. It isn't necessarily bad if the answer is "GPL", but we
> > all need to know this.
>
> You might consider consulting with a lawyer at your university.
> Universities sometimes have
> lawyers for this sort of thing.
+1
Note that any GPLed codebase like Singular or pari would also be viral
to high level code and I cannot believe that this is the way the GPL
is intended. Anything using readline, i.e. IPython, would be infected,
too, and that goes way too far IMHO (You can obviously use libedit or
no readline at all to work around this).
In the end the FSF seems to be rather wishy washy about the whole
thing, i.e. compare the recent discussion about Maxima where a
potential export licenses requirement was mandated by the DOE and it
was cleared by a FSF license engineer that adding the DOE note to
COPYING would be GPL compatible. That restriction IMHO clearly is
against the spirit of the GPL. But there are loads of people at the
FSF who get their panties in a twist about using binary firmware in
the Linux kernel, etc. And don't get me started on the [L]GPL V3 ...
> William
Licensing discussions just suck and are a waste of time. Sigh ....
Cheers,
Michael
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to sage-devel@googlegroups.com
To unsubscribe from this group, send email to
sage-devel-unsubscr...@googlegroups.com
For more options, visit this group at http://groups.google.com/group/sage-devel
URLs: http://www.sagemath.org
-~----------~----~----~----~------~----~------~--~---
