[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Is it possible to write GPL-Modules for closed-source Software?

From: Dave (from the UK)
Subject: Re: Is it possible to write GPL-Modules for closed-source Software?
Date: Tue, 08 Aug 2006 13:48:58 +0100
User-agent: Mozilla/5.0 (X11; U; SunOS sun4u; en-US; rv:1.7) Gecko/20060120

Stephan Kuhagen wrote:

Subject says it all... I'm working for an Institute/Company which does
scientific and medical imaging software. We have some OpenSource-Addicts in
the house (with me as the most addicted...) and try to bring at least some
of our software to the OpenSource-World. Now there is our
"Premium"-Software, that will stay closed source for long time (although we
try our best to convince the others...). If we can not release the software
under the GPL, we like to release at least some of it's modules under the
The software does not really need those modules, so it is not dependend on
them. The modules (there are hundreds of them) are loaded at runtime, not
statically linked.
Can I write a module, using the proprietary API of the software and release
it under the GPL? The GPL-modules would be available as precompiled module
for Windows/Linux/MacOSX and as source. I like to pack them into the
commercial installer (including the source of the module, of course) also,
but this is not required.

Is this possible without violating GPL, or is there no way to "undermine"
the closed-source-philosophy step-by-step...?


I'm no expert, but my interpretation is that there is nothing to prevent you releasing these modules under the GPL with source code, without you making the whole program GPL'ed.

Most commercial operating systems (AIX, IRIX, HP-UX etc) are all closed source. But all ship with open-source applications such as the GNU project 'wget'

The source to wget is available, but the source to the operating systems is not (Solaris is a partial exception). None of these operating systems need wget, but most will include it.

I know of a very nice commercial chess program that runs on a PDA

which can use open-source chess engines. The chess program ships with one engine (closed source module) but can use others.

I don't see anything wrong with what you want to do myself.

BTW, as a half-way house on the rest of the program, could it be released as open-source, but not GPL'ed? Sun's Solaris operating system is done this way, with most of the source available under a fairly restrictive license.

Some of it remains closed source, as Sun are not the copyright owners on parts of it - they just license the technology from somewhere else.

Dave (from the UK)

Please note my email address changes periodically to avoid spam.
It is always of the form:
Hitting reply will work for a few months only - later set it manually. (Web based Mathematica front end)

reply via email to

[Prev in Thread] Current Thread [Next in Thread]