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Hi,

I'm not very at ease in English and even less in legal English. This is why I'm asking you some precisions about CCLib LGPL License.

What are the differences (see Sections 5 and 6) between:
- a "work that uses the Library" ;
- a "derivative work of the Library" ;
- and a "work containing portions of the Library" ?

For example, if I want to use CCLib functions (or other LGPL libraries like Qt...) for an application in a commercial context, do I have the rights?
In this case, what are the obligations?

The "commercial context" I am evoking is:
- a proprietary software,
- using LGPL functions,
- compiled in an executable file,
- used only by the developing company,
- which is not to be distributed ;

Thanks for your answers.

[*]a "work that uses the Library" = you use the library as is, calling its methods and linking your project to it
[*]a "derivative work of the Library" = you have modified the library and you use this new version (which is therefore a "fork" from the initial project)
[*]a "work containing portions of the Library" = you copy some algorithms and insert the corresponding pieces of code in your own software

The most significant aspect of the LGPL license is that it's a non 'contaminant' license (contrary to the GPL one). Your are not obliged to adopt the LGPL license for your own software (contrarily to the GPL license that can only be "used" by other GPL softwares). However, you still have to share any modification of the code with its author and cite your sources.

But in your case - and this is also true with GPL license - as long as you don't distribute the software outside your company you have absolutely no obligation (apart from a moral obligation to help the source project of course ;).

Thank you, these concepts seem clearer.
But what about the inheritance of classes? For example from the QWidget in Qt, is it so a derivative work of the Library? Or just a use?

Hum, afaik I would say that it's standard "library usage" as you don't modify the library and you still have to "link" it.

See http://en.wikipedia.org/wiki/GNU_Lesser ... nheritance

The LGPL contains no special provisions for inheritance, because none are needed. Inheritance creates derivative works in the same way as traditional linking, and the LGPL permits this type of derivative work in the same way as it permits ordinary function calls

Thank you, with better search in English I could have found the answer to my question.
The inheritance implies so a derivative work.
Anyway in my case, if I don't distribute the software, it falls outside the scope of the license.

Thank you Daniel for all your answers, always so quick, accurate and with quality in this forum.