[XviD-devel] it doubts...

[Christoph Lampert]

On Fri, 20 Sep 2002, peter ross wrote:

> >This discussion has be fought several time:
> >http://www.gnu.org/licenses/why-not-lgpl.html
> >(I don't say I agree to Stallman's points, but it's the reference
> >document).
> 
> iam not arguing against the GPL (and happy to ignore the whole issue).
> but, please consider the following two cases:
> 
> A: Windows applications export a WinMain() function. the windows
>    operating system dynamically calls this when an applications
>    requests the execution of path/filename.
> 
> B: Windows VFW drivers export a DriverProc() function. the windows
>    operating system dynamicaly calls this when an application
>    requests a specific fourcc id.
> 
> A: A commerical application (e.g. the microsoft explorer, norton
>    commander, etc.) can be operated in such a way that a GPL
>    application is executed.
> 
> B: A commerical video application (e.g. adobe premier) can be
>    operated in such a way that a GPL video codec is utilized.

The question is "Does the _application_ get extented functionality from
calling the GPL program." An operating system /explorer doesn't get
extended functionality from calling a GPLed program. It's main purpose 
_is_ to be a plattform for calling other programs. The same holds for a
proprietary debugger, or compiler when executing a GPLed program. 
The features of the GPLed program do not extend the features of the
proprietary one. 

So the problem is not _executing_ a GPL application, but to use GPLed
code to extend the existing features of a proprietary program. 
Let's say you have a video player that doesn't know anything but how to
call a codec. Then that program would be of less functionality (or even
useless) without the codecs, and if it relies on a GPLed codec, that would
be forbidden use. 

> A: A commerical application can be written to execute a specific
>    GPL'd application.
> 
> B: A commerical video encoding application can be written to utilize
>    a specific GPL'd video codec.

This A is different from the other A's: A proprietary application 
_executing_ a GPLed application to extend it's functionality is not 
allowed, either. 

> Could somebody point out to me the difference between case A and B?

I tried... from my point of view...

Christoph