On Aug 30, 2007, at 8:32 AM, Jeff Eaton wrote:
GPL software *may not derive from non-GPL components* unless the copyright holders make them GPL'd as well. This is, according to the GPL, to protect the GPL license from being abused by companies that write proprietary software with a thing GPL'd "wrapper" that is useless when not used with the pricey software.
I'm all behind this reasoning. However....
I'll quote Brett Smith, the helpful GPL guy who spent a couple days hashing this out with me.
---- Perhaps you meant some kind of web services API, like a REST interface. That's a little more borderline.
There could also be other ways to construct the bridge that even more clearly avoid making a derivative work. For example, if the bridge didn't call functions from either program, and instead just read from or wrote to their underlying databases directly, that probably wouldn't create a derivative work. If there were command-line tools available that the bridge could call to help with its work, using system() or similar functionality, that probably wouldn't make a derivative work either.
I should also point out that if CMS developers want to make this sort of bridge development unambiguously okay, they could do so by providing some sort of licensing exception as described at <http://www.fsf.org/licensing/licenses/gpl- faq.html#LinkingOverControlledInterface>. This requires the assent of all the copyright holders, so I realize it may not be a feasible option for every free CMS, but it is out there.
This reasoning seems to employ arguments made by the RIAA and MPAA, except to opposite effect. I write this as a GPL advocate and a big believer in open source. GPL open source software is greatly advantaged to dominate the software world eventually, but trying to force that through legal ownership assertions strikes me as a great way to undermine the whole movement. For example, this API argument: by prohibiting use of APIs to bridge differently-licensed applications (and aren't APIs developed *precisely* to bridge two different applications?) we're forcing a "dumbing down" of work (and sundry other potential problems and risks) by legally requiring the bypassing of established application methodologies (such as security protocols) to write direct queries to databases. How are we going to build an integrated world when GPL starts claiming rights to all that touch it? We're going from the freedom that comes from building a commons to the restriction that comes from making that commons a fenced-in zoo. Maybe I'm wrong and going off in high spirits for no reason. The net result, I fear, is the creation of a GPL ghetto where anybody with one foot in the proprietary -- i.e., real -- world is given reason to hesitate coming within a country mile of GPL, just when GPL apps are poised (and have already started) to transform the mainstream business world. Vivek Purl wrote:
Just for background this issue has come up because Joomla have decided to "fully" comply with GPL. This raised a few question for SMF team and they discussed it with FSF. The final result of that discussion is if php ( or any other scripting language ) which is distributed in source form is bridged to a non GPL software also distributed in source form then it violates the GPL.
The immediate effect for drupal is that VB and SMF bridges are violating GPL. It doesn't matter if its being distributed via d.o. or not.
So GPL apps are prohibited from touching non-GPL apps. I'll be snarky and say this is the kind of thing that happens when lawyers get involved. Time to stop developing software and start developing new licenses and lawsuits! Laura (who's still wondering what was wrong with GPLv2)