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General Category => Off topic => Topic started by: teopl on 09:30, 31 March 19

Title: Software licences blah blah
Post by: teopl on 09:30, 31 March 19
I am not sure where to put this, so I will put it here...

Please someone advice me on a simple question.

I started a cpctelera project and I want to release it (some time in the future when it's finished) and I would like not to have moral or legal problems with potentially using other people's code.

Specifically, I would use other people's source files (or functions) licenced with LGPL (maybe GPL/MIT), as part of my code, like for example font drawing routines, or music player (arkos), ...

Also I would like to:

- use LGPL myself
- modify the source I have taken
- include notion of original author
- include myself as contributor (if I made modifications to the original code)
- finally not to bother too much writing legal notions, but writing code  :)
Title: Re: Software licences blah blah
Post by: Arnaud on 10:08, 31 March 19
If you use GPL code and release your code as GPL and include original author (in external text file or into your code) all is alright.
Title: Re: Software licences blah blah
Post by: teopl on 10:20, 31 March 19
Thanks Arnaud, is LGPL the same regarding that?

Can I do this?

MIT -> LGPL
GPL -> LGPL

with including original authors in source file / text file all is ok?

And to lighten up this topic here is a funny comic I saw earlier  :laugh:
I guess some of us in the forum can be recognized here, at least with the "lot of old computers" part haha (I currently have 3 cpc's 464 and I just may buy another today)

(https://i.ibb.co/KjD1S5G/Capture.png) (https://ibb.co/bgFfD63)
Title: Re: Software licences blah blah
Post by: MaV on 23:01, 01 April 19
Unless there's any explicit reason to use LGPL for your own code, GPL is the way to go. That is if you want to use a copyleft licence that prevents others to use your source code without releasing their own modified code in return.

Especially:
Quote from: teoplGPL -> LGPL
This is not allowed. If it were, it would serve as a loop hole to allow people to use GPL'ed code with their own licence without releasing their source code when dynamically linking the code.
Therefore: not possible.
You can use MIT code with your own code and release it as GPL, but only in that direction. In no way can you release originally GPL'ed code under another, more permissive licence.

In any case, you have to comply by releasing the author's original copyright notice and adding your own notice.


In short, if you use and modify GPL'ed code, don't bother even thinking about releasing it under any other licence.


For further reading:
https://www.gnu.org/licenses/gpl-faq.en.html
and of course:
https://www.gnu.org/licenses/licenses.en.html
(but don't blame me when you're about to jump out of the window!)
Title: Re: Software licences blah blah
Post by: teopl on 19:54, 02 April 19
My main source will be sources from CPC RetroDev competition and I quickly counted there:

- about 20 LGPL
- about 30 GPL

so GPL is more popular.

I will also take a look how others handled there the legal and moral stuff.

I had no special reasons for LGPL except that I heard that it's more premisive but then again, it is nice to have these sources, so if GPL attributes to that, then I may use GPL.

Anyway, I will leave this for the project end, I mean the legal detail polishing, legal reading and jumping out of the window... :D
Title: Re: Software licences blah blah
Post by: andycadley on 19:32, 04 April 19

If you aren't planning on actually taking people to court over your code (and potentially spending a lot of money doing so), the MIT is honestly the best license. It's highly permissive and you won't put people off looking at your code if they might learn something from it, MIT licensed code can pretty much be mixed in with anything else if someone finds it useful.


If you use GPL code, then you are stuck with GPL and stuck having to plough through the legal requirements of any code samples you might get ideas from in case they're licensed under something that isn't GPL compatible.
Title: Re: Software licences blah blah
Post by: teopl on 20:35, 08 April 19
Ok, I see my ignorance now...

So I can't just choose license or mix licenses - if I use some GPL code, my complete code needs to be GPL also.
(and even if I could mix licenses I am not sure I would bother)

And I am OK with that, although I am not planning to take people to court :)

Thanks for responses.
Title: Re: Software licences blah blah
Post by: MaV on 10:32, 11 April 19
Quote from: teopl on 20:35, 08 April 19So I can't just choose license or mix licenses - if I use some GPL code, my complete code needs to be GPL also.
(and even if I could mix licenses I am not sure I would bother)
Exactly. Once you use GPL code from others you are stuck with releasing the code under GPL, the same goes for LGPL. Any other licence may or may not be used or "upgraded" to GPL, you would need to research that for every code with another licence.In effect, it's always much easier to stick with the licence from the original source, much more so when you intend to release your sources as well.
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