[General] TriCitizen new Tox client on Android

[nurupo]

> https://opensource.stackexchange.com/questions/6771/am-i-allowed-to-use-a-gpl-3-library-in-a-closed-source-web-application
> 
> 
> "As long as the user just _runs_ GPL-2 software, there should be no
> problem. GPL-3 is different."
Please don't link to random answers on stackexchange or similar websites 
as some sort of authoritative answers. Anyone can write anything they 
want on those kinds of websites and that doesn't make whatever is 
written on there true.
Instead, use the GPL-3.0 license text, accessible at 
https://github.com/TokTok/c-toxcore/blob/master/LICENSE to see what is 
allowed or not under the GPL. That's the single source of truth.
Also, as mentioned earlier, the GPL FAQ by FSF is also a good 
authoritative source at explaining the GPL: 
https://www.gnu.org/licenses/gpl-faq.en.html

> Am only running the binary of a GPL-2 derived work.
Firstly, c-toxcore is not a binary executable, it's a library. Secondly, 
you are not running it, instead you are linking it into your 
application, making it a single application, and then running your 
application, not just c-toxcore. Thirdly, I don't understand why you 
mention GPL-2 as it doesn't apply here, it's GPL-3.0 that applies here. 
c-toxcore is available only under GPL-3.0-or-later, and Trifa is 
dual-licensed under GPL-2.0-only and GPL-3.0-only, but the only option 
you have is to use Trifa under the GPL-3.0 when it gets combined with 
c-toxcore, as GPL-2.0 and GPL-3.0 are incompatible licenses and can't be 
combined into a single work (see 
https://www.gnu.org/licenses/gpl-faq.en.html#AllCompatibility).

---
Regards,
nurupo

On 2021-08-02 16:58, gary at mohan.net wrote:
> https://opensource.stackexchange.com/questions/6771/am-i-allowed-to-use-a-gpl-3-library-in-a-closed-source-web-application
> 
> 
> "As long as the user just _runs_ GPL-2 software, there should be no
> problem. GPL-3 is different."
> 
> Am only running the binary of a GPL-2 derived work.
> 
> On 2021-08-02 9:38 pm, nurupo wrote:
> 
>> Trifa includes c-toxcore and is licensed under GPL too. So you are
>> also violating Trifa's GPL license too.
>> Also, I'm not sure what you meant by saying that Trifa was available
>> as a binary. It makes no difference if it was available as a binary
>> or not, it's GPL, and if you if you include it in your app as a
>> dependency, you must comply with the GPL license.
>> 
>>> Everything I've read on this from real-world lawyers says
>>> copyright
>>> law trumps the GPL licence.
>> I'm sorry, but what you are talking makes no sense. Are you aware
>> of what the copyright law is and what licenses are used for?
>> 
>> Under the copyright law, you are not allowed to use a work without
>> permission from the copyright holder. Any such use constitutes
>> copyright infringement and the copyright holder might file a legal
>> suit against you.
>> 
>> If we ignore the GPL license of c-toxcore and Trifa for a moment and
>> assume they have no license, just the copyright, then you are not
>> allowed to use them until after you get permissions from *all*
>> copyright holders of c-toxcore and Trifa to be able to use them in
>> your app. (Actually, I think Trifa depends on some other GPL
>> software, at least x264 but maybe more, so you would need to seek
>> their permission too).
>> Did you get any permission from c-toxcore copyright holders to use
>> c-toxcore in the TriCitizen app? As one of c-toxcore copyright
>> holders, I can say that you did not, because I wasn't contacted
>> regarding this, and without my permission you aren't allowed.
>> 
>> A license is the copyright holders telling that everyone can use
>> their copyrighted work as long as they comply with the terms of the
>> license.
>> 
>> The only terms you can use c-toxcore under are GPL. If you are not
>> using c-toxcore under the GPL license, then by the copyright law you
>> are not allowed to use c-toxcore at all, as a copyright holder (all
>> c-toxcore contributors, including me) haven't explicitly allowed you
>> to. Since you aren't allowed to use c-toxcore, by extension, you
>> aren't allowed to use Trifa, since it includes c-toxcore.
>> 
>> Please resolve your GPL violation promptly.
>> 
>> ---
>> Regards,
>> nurupo