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GPLv2+ vs. GPLv3+ licensing for FGAddon.

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GPLv2+ vs. GPLv3+ licensing for FGAddon.

Postby AndersG » Thu Jan 04, 2018 9:47 am

abassign wrote in Wed Jan 03, 2018 9:00 pm:We wanted to release the aircraft under the GNU 3 license (this choice is correct)


Is there some particular permission in GNU GPL v2 (and not in GNU GPL v3) that you do not want to offer?
Otherwise "GNU GPL v2 or later" would be a much better choice since that is the license of most things in FlightGear and FGAddon.
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Re: What is the procedure for commit our work on FGAddon ?

Postby bugman » Thu Jan 04, 2018 1:18 pm

The FlightGear Policy Document says:

All contributions to the flightgear repository must be released under the GNU General Public License V2.0 with the “or any later version” option (GPL2+). All contributions to the simgear repository must be released under the GNU Library General Public License V2.0 with the “or any lager version” option (LGPL2+). All source code files should include the standard (L)GPL2+ header and the original author copyright statement. The authorship of subsequent modifications are not recorded within source code files – instead they are recorded in commit messages in the appropriate version control system.


So no GPLv3+ for now.

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Re: What is the procedure for commit our work on FGAddon ?

Postby Necolatis » Thu Jan 04, 2018 2:46 pm

GPL2+ would include GPL3, yes? What else would the plus mean?
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Re: What is the procedure for commit our work on FGAddon ?

Postby Thorsten » Thu Jan 04, 2018 3:01 pm

It means that it is licensed under GPL V2, but anyone who wants can re-license under GPL V3.

Whereas GPL V3 does not allow you to re-license as V2.
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Re: What is the procedure for commit our work on FGAddon ?

Postby erik » Thu Jan 04, 2018 3:38 pm

I think that document was meant for code only.
Wasn't FGAddon meant to support all Open Source licenses?

Update, according to:
http://wiki.flightgear.org/FGAddon
In August 2015, a new FlightGear policy document was written to codify the unwritten standards of the project[8]. With this document, the licensing policy for the FlightGear aircraft has been updated from being GPLv2-only to now being a GPLv2+ or GPL-compatible[9] stance. However, to combat licence proliferation complications for the integrity and good of the FlightGear project, it is strongly recommended that original content be GPLv2+ licensed.


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Re: What is the procedure for commit our work on FGAddon ?

Postby abassign » Thu Jan 04, 2018 5:01 pm

Thank Erik,

I find your note very important as reading it and reading what he writes the site https://www.gnu.org/licenses/license-list.en.html it seems clear that even the GPL 3 is compatible, with the statement:
"from being GPLv2-only to now being a GPLv2+ or GPL-compatible[9] stance"

Image

So it seems to me that the GPL 3, which I prefer, is perfectly compatible with what was written in the note previously shown by Erik.
So I ask others what they think of the matter, if the time has come to present a plane with the GPL 3 and make Stallman happy :) (That I knew him some time ago, and I must say that it is really a special person).

Thorsten wrote in Thu Jan 04, 2018 3:01 pm:It means that it is licensed under GPL V2, but anyone who wants can re-license under GPL V3.
Whereas GPL V3 does not allow you to re-license as V2.


From this post I see that Thorsten says what I think to understand, obviously being the most restrictive GPL 3, as written in the notes in this link: https://www.gnu.org/licenses/license-list.en.html it is not possible to go back and it is sincerely just what I want.
Last edited by bugman on Thu Jan 04, 2018 8:32 pm, edited 2 times in total.
Reason: Please do not quote the entire previous post.
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Re: What is the procedure for commit our work on FGAddon ?

Postby abassign » Thu Jan 04, 2018 6:38 pm

Another question, every XML or NASAL file must contain the type of license, the author etc ?
It seems that almost nobody does it, but in my work environment it is normal to proceed in this way.
However, I was looking for an XML TAG to insert such data, but it does not seem to be there. It is assumed that you have to enter this data as a comment, right ?

If I have to insert it as a commend, I thought I would include something like this:

Code: Select all
<?xml version="1.0" encoding="ISO-8859-1"?>
<!--
<author name="Adriano Bassignana" />
<copyright name="Adriano Bassignana" />
<license type="GPL">GNU/GPLv3 http://www.gnu.org/licenses/gpl-3.0.html</license>
-->
<PropertyList include="G91-R1B-common.xml">
    <sim> ....


Grazie per il vostro aiuto
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Re: What is the procedure for commit our work on FGAddon ?

Postby bugman » Thu Jan 04, 2018 8:44 pm

@Necolatis: As Thorsten says, GPLv2+ means you can relicense from GPLv2 to GPLv3+ (but only GPLv3+, not GPLv3). I.e. the current licence is GPLv2, but this can be updated to newer versions by other parties, recursively.

@Erik: GPL-compatible does not mean all open source. See the green licenses in the link provided by abassign: https://www.gnu.org/licenses/license-list.en.html. There are not many commonly used licences in the green list. Also note the text in abassign's screenshot:

Please note that GPLv3 is not compatible with GPLv2 by itself.


@Abassign, I think you need to read what you post more carefully ;)

Another question, every XML or NASAL file must contain the type of license, the author etc ?


For copyright law, no. If you wish to follow the FSF standard, then yes, absolutely every file needs a copyright notice, either within the file itself or in a README file located in the same directory (or subdirectory). But FlightGear does not follow the strict FSF standard.

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Re: What is the procedure for commit our work on FGAddon ?

Postby erik » Thu Jan 04, 2018 10:22 pm

I agree 'all Open Source licenses' was worded a bit too broad.

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Re: What is the procedure for commit our work on FGAddon ?

Postby abassign » Fri Jan 05, 2018 8:00 am

GPLv3+ This seems to be a good idea ...

On this site (Drupal) the problem of the use of the GPL3 + is commented very clearly: https://www.drupal.org/project/drupal_lwg/issues/1449452
Image

The problem of defining the very beginning of its work, the correct license I find essential.
The Wiki, but the opinions of all of us are not always clear, so it seems fair to me to express my doubts that I think they are also the doubts of many others who want to collaborate to produce something interesting in this project. I prefer to ask questions that seem more banal, but at least they can constitute correct operating procedures.

The reason why I'm interested in a GPLV3 or better GPLV3 + license comes from some points that are well described in this link:
http://www.ifross.org/en/what-difference-between-gplv2-and-gplv3
-----
What is the difference between GPLv2 and GPLv3?
GPLv3 of June 29, 2007 contains the basic intent of GPLv2 and is an Open Source license with a strict copyleft However, the language of the license text was strongly amended and is much more comprehensive in response to technical and legal changes and international license exchange.

The new license version contains a series of clauses that address questions that were not or were only insufficiently covered in version 2 of the GPL. The most important new regulations are as follows:

a) GPLv3 contains compatibility regulations that make it easier than before to combine GPL code with code that was published under different licenses. This concerns in particular code under Apache license v. 2.0.

b) Regulations concerning digital rights management were inserted to keep GPL software from being changed at will because users appealed to the legal regulations to be protected by technical protective measures (such as the DMCA or copyright directive). The effectiveness in practice of the contractual regulations in the GPL has yet to be seen.

c) The GPLv3 contains an explicit patent license, according to which people who license a program under the GPL license both copyrights as well as patents to the extent that this is necessary to use the code licensed by them. A comprehensive patent license is not thereby granted. Furthermore, the new patent clause attempts to protect the user from the consequences of agreements between patent owners and licensees of the GPL that only benefit some of the licensees (corresponding to the Microsoft/Novell deal). The licensees are required to ensure that every user enjoys such advantages (patent license or release from claims), or that no one can profit from them.

d) In contrast to the GPLv2, the GPLv3 clearly states that there is no requirement to disclose the source code in an ASP use of GPL programs as long as a copy of the software is not sent to the client. If the copyleft effect is to be extended to ASP use, the Affero General Public License, Version 3 (AGPL) must be applied that only differs from the GPLv3 in this regard.

-----

Therefore, with a GPL3 or GPL3 + license, I feel that our work is better protected, even if it retains the possibility of being incorporated into a project with a GPL2 or GPL2 + license.
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Re: What is the procedure for commit our work on FGAddon ?

Postby AndersG » Fri Jan 05, 2018 9:42 am

As far as I can see at a glance none of these improvements have much influence on a FlightGear aircraft use case.
Using GPL v3+ would be an obstruction to reuse parts in a GPL v2+ context such as FGAddon - basically forcing a move to GPL v3+ eventually.
In my opinion that would not be a good thing. Additionally, for the FlightGear aircraft use case the difference in what the receiver can do between GPL v2+ and GPL v3+ (apart from the GPL v2+ reuse case above) seems very small indeed. So why use GPL v3+?

Using GPL v3 without the "or later version" addition would be completely nuts in this case and I would not want to see any of that in FGAddon.
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Re: What is the procedure for commit our work on FGAddon ?

Postby Hooray » Fri Jan 05, 2018 10:17 am

I agree with AndersG, as a matter of fact, even just using the GPL also for non-core assets, i.e. fgdata/fgaddon, has been considered controversial by many folks over the years, including very senior contributors, even causing some incidents that were in violation of the GPL.

Especially the question how this impacts GPL'ed Nasal code assets and other modules using such modules/libs, either via copy/paste & adapt or by "including" such modules (which is often done implicitly during load time, think geo.nas, props.nas)

FG Aircraft Licenses, continued
stuart wrote:As an example of this, see the AH-1 discussion. The developers there initially wanted to license under a CC-NC license, but changed to a GPL license later. I'm glad they did, but I think a strong driver for this was the amount of Nasal code etc. that they had taken from the F-14, which of course was licensed under the GPL. So I don't think that non-GPL work will overtake the GPL content in importance.

(Sorry - I realize we're going round in circles here)

-Stuart



Autonomous F-14b demo
curt wrote:Making a linkage based argument is interesting, but it appears that most people do draw a separation between the code that implements the script engine, and the actual scripts themselves. I have never thought otherwise, although perhaps this particular specific discussion has never come up before.

So just to summarize, I have always viewed the relationship between flightgear and the nasal interpreter versus nasal scripts in the same way that Larry Wall has viewed the relationship between the perl interpreter and people's perl scripts. The interpreter doesn't force it's license on the scripts and the script authors have the freedom to choose the license terms that work best for their situation. And again, for derivative works (i.e. modifying an existing gpl nasal script, the gpl license must be honored and maintained and not obfuscated.) But for original works, I continue to believe the author has discretion over how to license his/her own work.

Best regards,

Curt.


bundling GPL'ed contents with non-GPL materials
bugman wrote:This is a grey area - it definitely not black and white. Because this could be called linking, but it could also be seen as using the FG API. The first you are not allowed to do, the second you are.


Subject: The GNU GPL license and unwritten rules of curtesy
bugman wrote:But once bundled with other components, this has a legal effect. The bundling of aircraft components together (FDM, 3D, sound, Nasal) to create a whole aircraft which is distributed as a single unit is not much different from bundling the FG code components together (FG, simgear, all FDMs, Nasal, MP, etc.) to create a whole - licence compatibility issues must be considered.
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Thanks & all the best,
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Re: What is the procedure for commit our work on FGAddon ?

Postby AndersG » Fri Jan 05, 2018 10:42 am

Hooray wrote in Fri Jan 05, 2018 10:17 am:I agree with AndersG, as a matter of fact, even just using the GPL also for non-core assets, i.e. fgdata/fgaddon, has been considered controversial by many folks over the years, including very senior contributors, even causing some incidents that were in violation of the GPL.


To this I just want to add that in my opinion using GPL v2+ for both the core FlightGear and FGAddon is a strong benefit as it allows content to move freely between the core and FGAddon as needed.
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Re: What is the procedure for commit our work on FGAddon ?

Postby bugman » Fri Jan 05, 2018 11:12 am

@Abassign: Although you state benefits for GPLv3+, which is true, it doesn't matter. FlightGear is GPLv2+ (and compatible). You have to take it or leave it.

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Re: What is the procedure for commit our work on FGAddon ?

Postby erik » Fri Jan 05, 2018 2:03 pm

Well there have been GPLv3 aircraft accepted for inclusion in FGAddon in the past (Pilatus PC-9 and variants) which I would hate to see revoked.

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