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Thread: Qt License

  1. #1
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    Default Qt License

    Hi,
    I read this http://blog.qt.nokia.com/2009/11/30/...sing-decision/ but i'm still confused. If i creat an aplication using Qt with LGPL license can i sell it? I need to share the source code of my aplication to sell it? Can't i sell it?

    What does mean "if dynamically linking to the Qt library"?

    Thanks

  2. #2
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    Default Re: Qt License

    You can sell it and you don't have to share the source code.

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    Default Re: Qt License

    "dynamically linking" means depending on the Qt DLLs (If windows) or .so files (If Linux).

    "statically linking" means Qt is part of your application as the extra files are not required, but this is not compatible with LGPL.

  4. #4
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    Default Re: Qt License

    In other words if you don't know what dynamically linking is, it means you are dynamically linking Qt.

  5. #5
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    Default Re: Qt License

    thanks Now I just don't understand when I need a comercial license :s

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    Default Re: Qt License

    You need a commercial license when: You wish to statically link and keep your source closed, or wish to make modifications to Qt which you wish to keep closed, or wish to obtain support from Nokia.

  7. #7
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    Default Re: Qt License

    I think you can buy the latter as a separate service for LGPL as well.

  8. #8
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    Default Re: Qt License

    Also one question that confuse me:
    Can I statically link qt against my app and sell it? (common procedure on windows, only app no additional libs, if libs license allow that of course)
    I read somewhere that I need to redistribute qt libs, so each "client" can simply use lib that suits them. (If I remember correctly LGPL don't allow me to modify any libs )

  9. #9
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    Default Re: Qt License

    You can statically link Qt only with commercial license.

  10. #10
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    Default Re: Qt License

    Yes, you can statically link against Qt and sell it (even without commercial license, Lesiok is incorrect there).

    However, your application would then be under GPL license automatically, and so the people who bought your application could request (and you must make available) the source code of your application.

    If you purchase a commercial license for Qt, you can use your own license.

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