Re: Qt license change
On Wed, Nov 18, 1998 at 04:52:03PM +0100, luther@maxime.u-strasbg.fr wrote:
> What is the proper way to use a library, does it only include using
> programs linked to it, or does it also extend to being able to develop
> software with it. Only the first is permited by the QPL, the second is not
> without buying the commercial Qt. If i am a software developper, the
> proper use of the Qt library for me is being able to use it to produce
> programs, isn't it ?
Firstly, copyright law apparently doesn't apply to how I can "use" software
-- only how I can copy it. So if you can legally get a copy, you can
legally use it for whatever you want.
More importantly, though, developing software for use with Qt is just the
same as linking things with Qt. I mean, really, if I write source code that
calls into Qt, and then I compile and link it with Qt, that's what I call
software development.
[...]
> selling, and if they give it away, what will they be selling then ?
I think they're taking the "commercial support for commercial users" risk.
The Free Qt and the Commercial Qt are the same program, but licensed
differently -- if you use the Free Qt, you have to make your application
free as well. Many companies don't want to do that, so they'll buy a
separate commercial license from Troll.
Notice how all Qt patches you distribute have to give permission "to deal in
the patch without restriction, including without limitation..." That means
Troll can relicense your Qt patch into their commercial Qt version, so
they'll always be allowed to commercially-license the latest and greatest
Qt, including patches from you, without legal restrictions.
Anyway, the QPL looks DSFG-free to me, so I think Qt can be distributed in
main.
Now, as for compatibility with the GPL (which would let us also include KDE
in main)... I don't know. I'm not even sure why we're allowed to link
BSDish programs with GPLed ones, aside from the "included with the OS"
clause. GPL seems quite vague about that.
Have fun,
Avery
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