On Thu, 2008-09-18 at 12:26 -0400, Randy Kramer wrote:
On Thursday 18 September 2008 11:27 am, drew Roberts
wrote:
So, are there any Free programs built around QT
that are not GPL?
Let me add a bit of confusion to this ;-) I work for the US Government.
As such, I am not allowed to copyright anything that I write for my job.
It is, by definition, public domain (if it is ever released to the
public and does not contain classified or restricted information). I
corresponded with Trolltech's law people to find out if I could write
completely public domain software using the GPL version of Qt. The
answer is, "No, you must place all software written with the GPL'ed Qt
under the GPL license unless you puchase a QPL license from Trolltech".
Since I am not allowed to copyright my work I cannot possibly place
anything under the GPL because that requires copyright. In order for me
to use Qt I had to purchase a license from Trolltech. This isn't so bad
since the US Government can probably afford it ;-) On the bright side,
most of my software will be released as public domain in the very near
future. At that time anyone who wants to use it can do whatever they
want with it. If they want to write GPL software they can take what
I've done and GPL whatever they add to it and release it as GPL since
public domain is compatible with the GPL. If they want to take it and
add proprietary extensions to it they can purchase a license from
Trolltech and go to town. If they want to keep all of it in the public
domain they'll have to purchase a license from Trolltech. So the short
answer is, yes, there are Free programs built around Qt that aren't GPL
but if you want to do something else with them you have to pick a
direction.
I can't answer that definatively. I know KDE is
(being?) ported to
Windows, but I guess they manage to do that as free software (i.e.,
under the GPL license of Qt). It seems to me I've heard of some
commercial programs using (or planning to use) Qt, but I can't recite
any names.
I know of one commercial program that uses Qt and I'm sure there are
many more. The one I am familiar with is Interactive Visualization
Systems Fledermaus. I have reason to believe that SAIC may port some or
all of their SABER program to Qt in the near future. I am sure there
are many more examples around.
To do this
legally, one would have to purchase a commercial license right? And
then all
contributors would also need commercial licenses
right? The mind
boggles.
Yup, and, iirc, the original terms of Qt's dual license required that
you make a decision up front--if you were going to develop a commercial
application under the commercial (not GPL) license, you had to decide
when you started developing your application, and from that point, pay
for Qt. (If that was not for Qt, it was for some other dual licensed
library.)
Yes. That is how it works. You can, however, download a timed demo
license if you want to try it out before you buy. One interesting thing
about the licenses is that they aren't "seat" licenses. They are
assigned to a person and can only be changed to another person after six
or more months. Pretty clever actually ;-)
--
Jan 'Evil Twin' Depner
http://www.thecfband.com
"Microsoft has a new version out, Windows XP, which according to
everybody is the 'most reliable Windows ever.' To me, this is like
saying that asparagus is 'the most articulate vegetable ever.'"
Dave Barry