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Question about section 5 and 6 of LGPL license



  • I'm reading the LGPL license terms and when I got to section 5 and 6 I couldn't fully understand what I was reading. The part I'm concerned about is:
    [quote]
    5.
    ( ... )
    A program that contains no derivative of any portion of the
    Library, but is designed to work with the Library by being compiled or
    linked with it, is called a "work that uses the Library". Such a
    work, in isolation, is not a derivative work of the Library, and
    therefore falls outside the scope of this License.

    However, linking a "work that uses the Library" with the Library
    creates an executable that is a derivative of the Library (because it
    contains portions of the Library), rather than a "work that uses the
    library". The executable is therefore covered by this License.
    Section 6 states terms for distribution of such executables.

    ( ... )

    1. As an exception to the Sections above, you may also combine or
      link a "work that uses the Library" with the Library to produce a
      work containing portions of the Library, and distribute that work
      under terms of your choice, provided that the terms permit
      modification of the work for the customer's own use and reverse
      engineering for debugging such modifications.
      ( ... )
      [/quote]
      My understanding of the above is:
      an executable that uses the Library constitutes a derivative work. As such, the executable falls under the terms of this license. I may redistribute such executable under the terms of my choice, but these terms must permit the end-user to modify the work for his own use, and permit him to reverse engineer my redistributed work for his own usage and debugging purposes - in other words the end-user must be allowed to reverse engineer my work and he must be provided with the source code for any modifications (or, he must be permitted to make modifications to the executable itself).

    Am I correctly understanding it?


  • Lifetime Qt Champion

    Hi,

    Licensing questions are better asked to a lawyer. It's beyond the scope of this forum



  • I understand, thank you for replying ;)


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