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SumDude

LGPL and GPL license

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I just read both license and i realized i don''t know Lawyer-nese. All i ask is that someone clarify what they mean. Does GPL mean that anything i use from the source code MUST be released freely and not be allowed to release it commerically? Does LGPL mean i can use the Library for a commercial product UN-CHANGED and if it is changed i gotta release the source code?

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In short;

GPL - if you use GPL code in your code, YOUR code must be GPL (aka: provide full compilable source to your prog)

LGPL - if you use LGPL code in your code, YOUR code must be GPL, unless you link dynamically to the LGPL code, in which case you only need to provide the source to the LGPL code you link to.

Right?

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I am not a lawyer.

GPL -> If you distribute something you used the source code with, must be released all your source. You can release it commerically if you feel like it. If your price is too much, most people will compile it and distribute the binaries free.

If your borrowed code is very small, it does not have to be released. There is no line where you cross, but Richard Stallin said lower than 1-5% is ok.

LGPL -> If you modify the library, you must release the library. You do not have to release your source if you use a LGPL library. Example: If you write a program using SDL, you do not have to release your source. You can releaes it commerically.

~~~~~
"Go on then" - benjamin bunny.
Download and play Slime King I.

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Use of GPL code in your application means your whole application must be licensed under the GPL. The license requires you to provide the source code of the application at no additional charge to people you distribute the application to.

Nothing stops you from actually selling your application (but, as dede said, if people feel you charge them too much they''ll just undercut you). Additionally, particularly in the case of a game, ''resources'' like art, music, levels, story scripts ... do not fall under the GPL. They cannot be redistributed without your permission.

By the way, dede, I am not aware of any clause in the GPL absolving you from ''small'' inclusions - aside the fact that such violations would be harder to catch. "Stallman said" has no legal value.

As for the LGPL, the library must be clearly separated from your program (e.g. DLL), and users must either be able to substitute a ''fresh'' unmodified copy of the library or you must provide them the needed source code to rebuild a library usable with your program.
That''s the criterion to use as to whether you must provide the source code. Statically linking would make that impossible and would mean your whole application would have to be licensed under the LGPL.


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quote:
Original post by Fruny
Additionally, particularly in the case of a game, ''resources'' like art, music, levels, story scripts ... do not fall under the GPL. They cannot be redistributed without your permission.

Unless specified. There is a few GPL''d tile sets, although I''m not exactly sure how that would work in a court of law.
quote:
By the way, dede, I am not aware of any clause in the GPL absolving you from ''small'' inclusions - aside the fact that such violations would be harder to catch. "Stallman said" has no legal value.
The wording in the license is ''derived'' works. You must release the source code on all derived works. There is a legal limit when a work becomes derived. I''m not sure what that limit is, however, since I don''t study law.

~~~~~
"Go on then" - benjamin bunny.
Download and play Slime King I.

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