[Lazarus] [OT] About licences

[Marco van de Voort]

On Sat, Mar 26, 2011 at 02:43:45PM +0100, Kjow wrote:
> I need some help to understand the licences world, probably due my not
> English origins I have some difficulties to understand the terms of
> various licences and their relating limitations.
> Do you know a simple and clear site that explain all terms in few words?
> 
> e.g. (these are only explicative projects):
> - Lazarus is under LGPL, I understood that I can use it to make also
> commercial products without costs (of course, if/when I start earn
> money I'll donate to community :) ).

Lazarus (the IDE) is under GPL, LCL and other libraries are under
LGPL-with-exception.  Same for FPC, compiler GPL, libs under
LGPL-with-exception.
 
> - GLScene is under MPL, I understood that I can use it to make also
> commercial products without costs, but I need to mention somewhere on
> my product that I developed it with GLScene. My code could be closed,
> but I modify glscene code I should release it.

If I understood it correctly, MPL is pretty much a corporate wording of the
LGPL. 

MPL is incompatible with GPL/LGPL, but since Lazarus/FPC use
LGPL-with-exception, I don't know if that still creates a problem, since
that exception essentially defangs the copyleft.

> - Audorra is under MPL 1.1, I don't understood the differences between
> GLScene and Audorra licences. In their site is reported:
> 
> "Audorra is licensed under the MPL 1.1. Because this license is
> incompatible to the common open source license "GPL", you may use the
> project under the GPL or LGPL.
> Please remember: When linking against libraries, which are licensed
> under the GPL (like Acinerella), your project automatically falls
> under the same license. "

Lazarus and FPC do not contain GPLed library code themselves. (but they
might provide headers to libs that do).

The only problem is designtime code. This links into the IDE, and thus
touched the GPL. However, the GPL only activates on distribution, so unless
you plan to release Lazarus with MPL stuff preinstalled, there is no
problem.
 
> What this means? If I use Audorra with Lazarus+GLScene I need to
> release my project with GPL or LGPL licence?
> (PS I tried audorra and it uses acinerella.dll to reproduce sounds)

Both LGPL and MPL only pertain to the bits that they apply to, not to the
rest of the project.

The GPL is different, and the ancinerella bit is a big issue, which would
make the whole thing GPL. (there are some exceptions though)


See also http://wiki.freepascal.org/licensing

> - Acinerella is under GPL, I don't understood very well what this
> means... Using a product under GPL it must remain under GPL/open
> source/no-commercial?

There are a million writeups on the web more verbose and complete than I can
repeat here.
 
> if I want to protect my closed-source software, is it enough to place
> a my own "hand-wrote" disclaimer, or I need to register it somewhere?

No, copyright is automatic. Just claim you wrote it in the header, that
should be enough. (and afaik that is not even necessary, but makes disputes
easier)

> PS I mean only a legal-oriented question, not a moral one. I'll donate
> for sure to all project that will permit me to earn money (if I will
> :p ) and I'll mention all of these into credits and into the eventual
> website. But for this I need to know how I can do all in a legal
> way...

Afaik Lazarus/FPC does not force credits at all. (but it is good practice to
do so).

The exact details about advocacy clauses in MPL, I don't know.