[Zope-dev] ZPL and GPL licensing issues

Gregor Hoffleit gregor@hoffleit.de
Thu, 21 Jun 2001 17:28:40 +0200


On Thu, Jun 21, 2001 at 11:08:30AM -0400, Jim Penny wrote:
> OK, consider this from another point of view.  If I have an operating
> system may I install a piece of GPL software on the operating system?
> May I redistribute the operating system?  With the GPL software?
> May I invoke/run the GPL software?
> 
> My understanding is that the answer to every one of these is yes.
> 
> May I modify the GPL software and distribute it without giving
> downstream the same opportunity.  Clearly no.
> 
> Now, s/operating system/zope/g
> 
> Do the answers to the questions change?  And, if so, why?
> 
> >From my perspective, and I think from fog's the answer is that
> it should not change the answers.
> 
> Maybe the easy way out of this is to simply declare zope an
> "operating system" rather than an "application".  Snippy
> thoughts cut here.

The specific exception in the GPL reads:

    However, as a special exception, the source code distributed need not
    include anything that is normally distributed (in either source or
    binary form) with the major components (compiler, kernel, and so on) of
    the operating system on which the executable runs, unless that component
    itself accompanies the executable.

I.e. if you declared Zope an operating system on its own (which is certainly
arguable), then you could link GPL components with Zope (be it scripts, Zope
products, or C libraries) without worrying about the license of Zope.

Still, this would not include add-ons to Zope that are not distributed with
the main Zope distribution.

I.e. you would not be allowed to use ZPL add-on products alongside with GPL
components (the add-ons didn't come with the OS, therefore the exception
doesn't cover them).

Strange, isn't it ?


    Gregor