Velocity Reviews - Computer Hardware Reviews

Velocity Reviews > Newsgroups > Programming > Python > Big development in the GUI realm

Reply
Thread Tools

Big development in the GUI realm

 
 
RM
Guest
Posts: n/a
 
      02-07-2005
For all you GUI developers, things just got a little more interesting.
Trolltech will soon be offering the QT GUI toolkit for Windows under
the GPL license. That means that PyQt may become a much more popular
option in the near future. Unfortunately, some things available for
the commercial customers of Trolltech are not available to the GPL
users. For example, from their FAQ, it seems that no precompiled
binaries will be provided. Support for comercial compilers will not be
built in, only for gcc (through Cygwin?). Also, their database drivers
will not be available. Oh, well, I guess you can't have it all. Good
news though!

See more here:

www.trolltech.com

I wonder how this is going to affect the GUI landscape.

 
Reply With Quote
 
 
 
 
Michael Goettsche
Guest
Posts: n/a
 
      02-07-2005
On Monday 07 February 2005 17:52, RM wrote:
> For all you GUI developers, things just got a little more interesting.
> Trolltech will soon be offering the QT GUI toolkit for Windows under
> the GPL license. That means that PyQt may become a much more popular
> option in the near future. Unfortunately, some things available for
> the commercial customers of Trolltech are not available to the GPL
> users. For example, from their FAQ, it seems that no precompiled
> binaries will be provided. Support for comercial compilers will not be
> built in, only for gcc (through Cygwin?). Also, their database drivers
> will not be available. Oh, well, I guess you can't have it all. Good
> news though!
>
> See more here:
>
> www.trolltech.com
>
> I wonder how this is going to affect the GUI landscape.


Not 100% right. Only drivers for commercial databases will not be included,
mysql and co. are available.


 
Reply With Quote
 
 
 
 
Luke Skywalker
Guest
Posts: n/a
 
      02-07-2005
On Mon, 7 Feb 2005 18:30:18 +0100, Michael Goettsche
<(E-Mail Removed)> wrote:
>Not 100% right. Only drivers for commercial databases will not be included,
>mysql and co. are available.


What I find weird, is that I always understood the GPL meaning that
you must give back any contribution you made to the source code of the
GPLed code, but not if you're just using either a binary distribution
(eg. a DLL) or if you copy/pasted the code as is, with no changes on
your own.

If this is true, then the fact that Qt is now GPLed for Windows means
that I should be able to use this widget set even in commercial apps
since I'm not making any change to Qt, just using it.

Am I totally off-target?

Cheers
Luke.
 
Reply With Quote
 
Fredrik Lundh
Guest
Posts: n/a
 
      02-07-2005
"Luke Skywalker" wrote:

> What I find weird, is that I always understood the GPL meaning that
> you must give back any contribution you made to the source code of the
> GPLed code, but not if you're just using either a binary distribution
> (eg. a DLL) or if you copy/pasted the code as is, with no changes on
> your own.
>
> If this is true, then the fact that Qt is now GPLed for Windows means
> that I should be able to use this widget set even in commercial apps
> since I'm not making any change to Qt, just using it.
>
> Am I totally off-target?


yes. for details, see the "Combining work with code released under the
GPL" section on this page:

http://www.gnu.org/licenses/gpl-faq.html

</F>



 
Reply With Quote
 
Luke Skywalker
Guest
Posts: n/a
 
      02-07-2005
On Mon, 7 Feb 2005 19:41:11 +0100, "Fredrik Lundh"
<(E-Mail Removed)> wrote:
>> Am I totally off-target?

>
>yes. for details, see the "Combining work with code released under the
>GPL" section on this page:


Mmmm.. The FAQ isn't very clear about whether it's allowed to write a
proprietary EXE that calls a GPLed DLL:

"However, in many cases you can distribute the GPL-covered software
alongside your proprietary system. To do this validly, you must make
sure that the free and non-free programs communicate at arms length,
that they are not combined in a way that would make them effectively a
single program. The difference between this and "incorporating" the
GPL-covered software is partly a matter of substance and partly form.
The substantive part is this: if the two programs are combined so that
they become effectively two parts of one program, then you can't treat
them as two separate programs. So the GPL has to cover the whole
thing."

Considering the fact that the Qt DLL exist by themselves, that the
version used is the one provided by Qt, and that the EXE uses a
standard, open way to communicate with it, the above does seem to say
this use would be valid. Anybody knows of a similar case and the
output?

Luke.

 
Reply With Quote
 
Fredrik Lundh
Guest
Posts: n/a
 
      02-07-2005
Luke Skywalker wrote:

> Considering the fact that the Qt DLL exist by themselves, that the
> version used is the one provided by Qt, and that the EXE uses a
> standard, open way to communicate with it, the above does seem to say
> this use would be valid.


http://www.gnu.org/licenses/gpl-faq....ereAggregation

"/.../ If modules are designed to run linked together in a shared address
space, that almost surely means combining them into one program.

By contrast, pipes, sockets and command-line arguments are
communication mechanisms normally used between two separate
programs. So when they are used for communication, the modules
normally are separate programs. But if the semantics of the
communication are intimate enough, exchanging complex internal
data structures, that too could be a basis to consider the two parts
as combined into a larger program."

</F>



 
Reply With Quote
 
Grant Edwards
Guest
Posts: n/a
 
      02-07-2005
On 2005-02-07, Luke Skywalker <(E-Mail Removed)> wrote:
> On Mon, 7 Feb 2005 19:41:11 +0100, "Fredrik Lundh"
><(E-Mail Removed)> wrote:
>>> Am I totally off-target?

>>
>>yes. for details, see the "Combining work with code released under the
>>GPL" section on this page:

>
> Mmmm.. The FAQ isn't very clear about whether it's allowed to write a
> proprietary EXE that calls a GPLed DLL:


Yes it is allowed. You are always allowed to write proprietary
programs that incorporate GPL code. What you are not allowed
to do is distribute those programs under a license that's not
the GPL.

> Considering the fact that the Qt DLL exist by themselves, that the
> version used is the one provided by Qt, and that the EXE uses a
> standard, open way to communicate with it, the above does seem to say
> this use would be valid. Anybody knows of a similar case and the
> output?


My understanding is that what you propose is not valid. An EXE
that uses a GPL'd DLL must be distributed according to the
terms of the GPL. Were that not the case, the LGPL would not
have been needed.

--
Grant Edwards grante Yow! Yow! Maybe I should
at have asked for my Neutron
visi.com Bomb in PAISLEY--
 
Reply With Quote
 
Tim Churches
Guest
Posts: n/a
 
      02-07-2005
Fredrik Lundh wrote:

>Luke Skywalker wrote:
>
>
>
>>Considering the fact that the Qt DLL exist by themselves, that the
>>version used is the one provided by Qt, and that the EXE uses a
>>standard, open way to communicate with it, the above does seem to say
>>this use would be valid.
>>
>>

>
> http://www.gnu.org/licenses/gpl-faq....ereAggregation
>
> "/.../ If modules are designed to run linked together in a shared address
> space, that almost surely means combining them into one program.
>
> By contrast, pipes, sockets and command-line arguments are
> communication mechanisms normally used between two separate
> programs. So when they are used for communication, the modules
> normally are separate programs. But if the semantics of the
> communication are intimate enough, exchanging complex internal
> data structures, that too could be a basis to consider the two parts
> as combined into a larger program."
>
></F>
>
>

Yes, that is what the FSF GPL FAQ says. However, the GPL itself says:

"[Section 0] Activities other than copying, distribution and
modification are not covered by this License; they are outside its scope."

There is not, AFAICS, any formal definition of what is meant by
"modification" in the GPL.

Section 2.b of the GPL says:

"b) You must cause any work that you distribute or publish, that in
whole or in part contains or is derived from the Program or any part
thereof, to be licensed as a whole at no charge to all third parties
under the terms of this License."

and Section 2 goes on to say:

"These requirements apply to the modified work as a whole. If
identifiable sections of that work are not derived from the Program, and
can be reasonably considered independent and separate works in
themselves, then this License, and its terms, do not apply to those
sections when you distribute them as separate works. But when you
distribute the same sections as part of a whole which is a work based on
the Program, the distribution of the whole must be on the terms of this
License, whose permissions for other licensees extend to the entire
whole, and thus to each and every part regardless of who wrote it."

Thus, it seems to me, and to the expert legal advice which we sought
(note the scope of the advice was Australian law only) that provided no
GLPed source or object code is mixed, included or combined with
non-GPLed code, and that the GPLed and non-GPLed code are distributed or
otherwise made available in packages which are very clearly separate
works, and that any interaction between the two is restricted to
runtime, then the GPL does not require that non-GPLed code to be
distributed under the GPL.

It is arguable whether that opinion is at odds with the sentiments
expressed in the FSF GPL FAQ - it depends whether importing two python
modules into the same namespace is considered equivalent to, as the FAQ
says, "run linked together in a shared address space", but ultimately,
it is what the GPL license text says, not what the FSF FAQ says, which
matters.

Note that I am not in favour of or advocating any attempt to circumvent
or undermine the GPL. I just think it is important to be guided by what
software licenses actually say, rather than by what the authors of the
licenses wished they had said in retrospect.

Tim C

 
Reply With Quote
 
Damjan
Guest
Posts: n/a
 
      02-07-2005
> For all you GUI developers, things just got a little more interesting.
> Trolltech will soon be offering the QT GUI toolkit for Windows under
> the GPL license. That means that PyQt may become a much more popular
> option in the near future.


This applies to QT-4 only.
I wonder how much of PyQT is ready for QT4?

Anyway its time for a PyQT based VB-killer [ a GPL one ].


--
damjan
 
Reply With Quote
 
Steve Holden
Guest
Posts: n/a
 
      02-07-2005
Luke Skywalker wrote:

> On Mon, 7 Feb 2005 18:30:18 +0100, Michael Goettsche.
> <(E-Mail Removed)> wrote:
>
>>Not 100% right. Only drivers for commercial databases will not be included,
>>mysql and co. are available.

>
>
> What I find weird, is that I always understood the GPL meaning that
> you must give back any contribution you made to the source code of the
> GPLed code, but not if you're just using either a binary distribution
> (eg. a DLL) or if you copy/pasted the code as is, with no changes on
> your own.
>
> If this is true, then the fact that Qt is now GPLed for Windows means
> that I should be able to use this widget set even in commercial apps
> since I'm not making any change to Qt, just using it.
>
> Am I totally off-target?
>

Yes.

The GPL only dictates what you *must* do when you re-distribute GPL'd
code, or code derived from GPL'd code - and there's substantial room for
disagreement about what is and what is';t a derived product, with a
recent opinion suggesting that the FSF would regard importing a GPL'd
Python module as making your Python program constitute a "derived product".

As long as you don't redistribute anything you are free to do whatever
you want with GPL'd code. The intent of the license is essentially to
stop proprietary freeloaders from benefiting from GPL'd code without
giving anything back to the community. Microsoft choose to call this
"viral", but as usual they are talking out of their wallet.

regards
Steve
--
Meet the Python developers and your c.l.py favorites March 23-25
Come to PyCon DC 2005 http://www.pycon.org/
Steve Holden http://www.holdenweb.com/
 
Reply With Quote
 
 
 
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
GIDS 2009 .Net:: Save Big, Win Big, Learn Big: Act Before Dec 29 2008 Shaguf ASP .Net 0 12-26-2008 09:29 AM
GIDS 2009 .Net:: Save Big, Win Big, Learn Big: Act Before Dec 29 2008 Shaguf ASP .Net Web Controls 0 12-26-2008 06:11 AM
GIDS 2009 Java:: Save Big, Win Big, Learn Big: Act Before Dec 29 2008 Shaguf Python 0 12-24-2008 07:35 AM
Re: Re: Big development in the GUI realm Tim Churches Python 8 02-10-2005 12:19 AM
Re: Re: Big development in the GUI realm Tim Churches Python 20 02-09-2005 12:24 PM



Advertisments