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General Open Source Software License Question



  • Dear Community,

    atm my Software is under development or only internal usage atm.
    As far as I know are most of the Qt GUI LGPL (I don't use charts, Data Virtualization, Virtual Keyboard, webassembly or Network Authorization).
    So Linkage to proprietary software is legal. I use dynamic linkage.
    Does it matter if I use import lib (.lib) or via LoadLibrary? Can a Proprietary Software use LGPL import libs?
    Qt is unchanged. I use the Qt Web Installer.

    and question about MIT and BSD (FreeBSD Style):
    The licenses are saying the copyright notice have to be included.

    in my software I have under Menu Help:

    About Qt
    About Third Party Libraries
    About The Software.

    if you click on About Third Party Software there is a list of all Third Party Libraries and their Licenses (whole text).
    Does it satisfy the requirements for BSD and MIT? I mean it is easy to find. Who does not know "Help > About" ? at first you will see a list of all third party libraries. And if you click on them you get the full license text. If you want to you can google it and download the code. They are unchanged. But afaik BSD and MIT do not require releasing them as open source anyway. But If I changed it I would have released them as open source under the same License.

    P.S. I am unsure which license I will use yet.


  • Lifetime Qt Champion

    Hi,

    For such questions, there's only one source of authority: a lawyer specialized in licenses.

    You will have here at most personal comprehension of the licenses but by no means has it any legal value as we are not lawyers.

    What you currently did looks correct.

    Whether you link to it or you load it dynamically makes no difference AFAIK with regard to the licence.

    Again: ask a lawyer.



  • @SGaist
    Thanks I will ask a Lawyer before I release it.

    The cheaper but more annoying and complex way would be ask the real authors of every affected library.



  • Does it satisfy the requirements for BSD and MIT? I mean it is easy to find. Who does not know "Help > About" ? at first you will see a list of all third party libraries.

    You can look how other companies (like Apple, Google, or, surprise, Qt itself) are handling 3rd-party BSD/MIT licensed code. It may be buried deep down in app or documentation and it's still ok because persistent user can find it.

    But If I changed it I would have released them as open source under the same License.

    BSD and MIT allow any modifications in code without requirement to publish them, as long as you comply with their terms. Read licenses, they are very concise..


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