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code_glitch
17-10-2010, 09:01 PM
This has been nagging me for quite a bit now, the GPL is a free license and the way I see it

GPL CODE + YOUR CODE = MUST BE GPL
and
GPL = FREE

so my question is: Can I make a commercial app and sell it for profit if it contains GPL code as long as I provide the GPL bits for free??? Is that legal?

and scenario two: If I make a library that interacts with GPL code and I give it away free (open source), can the end user use my library for making apps that he/she can sell for profit legally?

sorry if this doesnt make too much sense, its late and etc... But just wondering if I have to avoid all gpl code, because that might be a little tricky...

cheers,
code_glitch - The recently promoted guy.

phibermon
17-10-2010, 09:11 PM
http://en.wikipedia.org/wiki/GNU_General_Public_License

"GPL explicitly states that GPL works may be sold at any price."

"The GPL additionally states that a distributor may not impose "further restrictions on the rights granted by the GPL". This forbids activities such as distributing of the software under a non-disclosure agreement or contract. Distributors under the GPL also grant a license for any of their patents practiced by the software, to practice those patents in GPL software."

--

But linking, that's the issue, and it can restrict your licence or even force you to use GPL in some circumstances. Carry on reading, it's a minefield. remember that the LGPL (http://en.wikipedia.org/wiki/LGPL) is quite common and should not be confused with the GPL.

LGPL allows you to use it, linking dynamic or static without having to worry, carry on and sell your works but include the licence and if you make modifications to LGPL code you must be prepared to make the changes public or distribute those changes with your application.

Andru
17-10-2010, 09:12 PM
so my question is: Can I make a commercial app and sell it for profit if it contains GPL code as long as I provide the GPL bits for free Is that legal?
Yes, if you will distribute source code of your application that you sell(for example any user can ask you for source code and you must give it, if you use GPL code in your application).

code_glitch
17-10-2010, 09:13 PM
Thanks for the extremely good advice. I looked over what I'm using, most of it is GPL/LGPL. I didnt think there was a difference, but thanks for the blisteringly fast reply. Now I know, that is fantastic news. Made my day (the hour or so left of it). This is really fantastic news.

cheers,
code_glitch.

code_glitch
17-10-2010, 09:18 PM
Sorry for the extra post, but this means I can release the Prometheus_Audio Second draft in around about 72 hours once its been tweaked a bit... That means in 72 hours or so, the world will have a pretty good idea of what Prometheus can do in its beta draft stage... Good news people. Spread the word, YAAAAY.

wooohooo,
code_glitch out in a very happy manner for today. XD

Andru
17-10-2010, 09:33 PM
LGPL allows you to use it, linking dynamic or static without having to worry, carry on and sell your works but include the licence and if you make modifications to LGPL code you must be prepared to make the changes public or distribute those changes with your application.
Hmm, then why so many developers of free software(not Open Source) doesn't use static linking? And why some libraries provide static linking only in commercial version(for example - SDL 1.3)? :) I don't remember well the license, but many people says that LGPL code can be linked statically only if you will distribute your code.