Calling GPL code from a Python application

Mike Meyer mwm at
Wed Jan 4 13:37:43 EST 2006

Heiko Wundram <modelnine at> writes:
>> Heiko Wundram <modelnine at> writes:
>>> The stance the FSF (and it's lawyers) take on this is that it is illegal
>>> to dynamically link applications that are not under a GPL-compatible
>>> license to GPL works
>> I doubt that, because it's simply not true. I can use GPL'ed code any
>> way I want to - that's part of the point of the GPL. I can change it
>> however I want, print it in whatever font I want on whatever material
>> with whatever other code I want.
> You're nitpicking here, if I may say so.

You can say so, but you'd be wrong. I'm not nitpicking - this is an
*incredibly* important distinction that makes possible much of my use
of GPL-ed code.

> (I guess pretty much nobody programs seriously just to jerk off to how good
> he is, everybody wants others to use what he has created)

You're only looking at why people write code and give it away for
free. That's the first time I've seen that, but it's as ignorant of
the real world as the far more common view that people only write
software for the puprose of selling it commercially.

Both viewpoints are wrong. The vast majority of the software written
is *never* redistributed in any way. It's written for inhouse use by
some organization, and never used outside of that organization in any
way. The last time I looked (I confess it's a number of deecades),
most of that software was written by various government organizations.

In my case, I get paid for building custom applications. If I use
GPL'ed software, I'm required to give my client the software under the
GPL (or, as you point out, a GPL-compatible license). I never bother -
I hand them a tarball and installation instructions and they install
it on their systems, or I install the stuff on their systems for them,
and it never goes anywhere else. I believe that's in compliance with
the GPL, because they get all the rights that the GPL wants them to
have. They aren't interested in selling or in any way redistributing
the software, so they don't care that they'd have to do so under the

As for the ego-boo, yeah, seeing thousands of downloads of your
software is cool. But so is tens of thousands of page views a day, or
knowing you saved your client thousands of dollars a day, or (in the
case of the government hackers) knowing your softwware helped put a
man on the moon.

> Anyway, it's not true either that if you link to a GPL-led library, your
> work must automatically be GPL. The FSF has specifically endorsed
> applications under several other OS-licenses which are basically more
> liberal than the GPL to link against GPL libraries. These licenses have to
> meet certain criteria, and I'm not exactly sure which, please go and see
> the FSF for more info. In case you create an immediate derivative work of
> the library (by changing it's sources directly), you have to put the
> resulting code under the GPL, of course, if you're going to distribute it.

Like I said, they may have changed it since I last looked. Good to
hear they have, otherwise most open source distributions would
probably be in violation. of the GPL.

Mike Meyer <mwm at>
Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information.

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