[gdal-dev] Off topic. About GNU GPL; LGPL; MIT; etc license types.

[Even Rouault]

Selon "Antonio P." <aperezcarro at yahoo.es>:

Antonio,

I'm afraid I've not really understood how to fill your matrix, but here's my
understanding of the obligations of the licences. Take it with a grain of salt :
"I'm not a lawyer".

* If your application links to a GPL library, the whole application, including
your own code, is bound by the GPL. You must include the appropriate copyright
notice for the library and provide the user access to the source code of the GPL
library (including the modifications you may have done) and to the code of your
application too under the terms of the GPL.

* If your application links to a LGPL library, you must include the appropriate
copyright notice for the library and provide the user access to the source code
of the LGPL library (including the modifications you may have done in it). Your
application itself may be released under the terms you like.

* If your application links to a BSD library, well, that's depend of the BSD
licence. There are 2-clause, 3-clause and 4-clause variants of the BSD
licence... If it includes the following clause "Redistributions in binary form
must reproduce the above copyright notice, this list of conditions and the
following disclaimer in the documentation and/or other materials provided with
the distribution", well just comply with it. Otherwise, if you don't distribute
any source code (and you don't have to), you have nothing to do. In any case,
the licence only covers the library code, not your application.

* The MIT licence is a bit similar, except that, the general understanding is
that it places no obligations if you distribute the library as a binary object.
But I've always found that the term "the Software" in the licence isn't very
explicit if it only covers only the source code or binaries generated from it.
So it might be nice to include the copyright notice somewhere if you distribute
it as a binary. If you distribute it as source code, it's clear that you must
include the copyright notice.

> I'd want to know your opinion, by apologising for this out-of-the-list
> question.
>
> I dont understand if I can or not use third soft components I'd want to add
> to my commercial application.
> I read and read and read GNU and GPL (are the same?) and LGPL, BSD; MIT ...
> and I have not any conclusion (I'm very confused)
>
> Starting at the point my appplication are going to be commercial, what can
> and cannot I do whith the 'free' licenses types ?
> What about my own development ? It can exist two uses :
> 1.- I use third component (exe, lib + source code or full source code)
> 2.- I use full source code and I have modified some parts.
>
> The check list is then :
>             Use exe/dll     Full source code    Modified source code
> GPL
> LGPL
> FOSS
> MIT
> BSD
>
> And the answer for each item :
> - Yes: You can use totally free.
> - No1: You have to redistribute your whole own software
> - No2: You have to redistribute only the modified original source code
>
> And whats about the obligation to show copyright ?
> - Yes : You have to show a GNU/LGPL/etc copyright text.
> - No1 : You only have to inform that you use a third component by its name.
> - No2:  You have not to show no copyright neither references.
>
> Can anybody fill the list ? Thanks