GNU Lesser General Public License (LGPL) | Qt 5.13

Qt 5.13 | GNU Lesser General Public License (LGPL)

Qt 5.13.1 Reference Documentation

# GNU Lesser General Public License (LGPL)

Qt is available under the GNU Lesser General Public License version 3.

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Reference:

- GNU Lesser General Public License, version 3

## LGPL version 3

                         GNU LESSER GENERAL PUBLIC LICENSE
                             Version 3, 29 June 2007

       Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
       Everyone is permitted to copy and distribute verbatim copies
       of this license document, but changing it is not allowed.

        This version of the GNU Lesser General Public License incorporates
      the terms and conditions of version 3 of the GNU General Public
      License, supplemented by the additional permissions listed below.

        0. Additional Definitions.

        As used herein, "this License" refers to version 3 of the GNU Lesser
      General Public License, and the "GNU GPL" refers to version 3 of the GNU
      General Public License.

        "The Library" refers to a covered work governed by this License,
      other than an Application or a Combined Work as defined below.

        An "Application" is any work that makes use of an interface provided
      by the Library, but which is not otherwise based on the Library.
      Defining a subclass of a class defined by the Library is deemed a mode
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        A "Combined Work" is a work produced by combining or linking an
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        The "Corresponding Application Code" for a Combined Work means the
      object code and/or source code for the Application, including any data
      and utility programs needed for reproducing the Combined Work from the
      Application, but excluding the System Libraries of the Combined Work.

        1. Exception to Section 3 of the GNU GPL.

        You may convey a covered work under sections 3 and 4 of this License
      without being bound by section 3 of the GNU GPL.

        2. Conveying Modified Versions.

        If you modify a copy of the Library, and, in your modifications, a
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      facility is invoked), then you may convey a copy of the modified
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         a) under this License, provided that you make a good faith effort to
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         b) under the GNU GPL, with none of the additional permissions of
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        3. Object Code Incorporating Material from Library Header Files.

        The object code form of an Application may incorporate material from
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         b) Accompany the object code with a copy of the GNU GPL and this license
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        4. Combined Works.

        You may convey a Combined Work under terms of your choice that,
      taken together, effectively do not restrict modification of the
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         b) Accompany the Combined Work with a copy of the GNU GPL and this license
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         c) For a Combined Work that displays copyright notices during
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         d) Do one of the following:

             0) Convey the Minimal Corresponding Source under the terms of this
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             recombine or relink the Application with a modified version of
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             1) Use a suitable shared library mechanism for linking with the
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         e) Provide Installation Information, but only if you would otherwise
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         Application with a modified version of the Linked Version. (If
         you use option 4d0, the Installation Information must accompany
         the Minimal Corresponding Source and Corresponding Application
         Code. If you use option 4d1, you must provide the Installation
         Information in the manner specified by section 6 of the GNU GPL
         for conveying Corresponding Source.)

        5. Combined Libraries.

        You may place library facilities that are a work based on the
      Library side by side in a single library together with other library
      facilities that are not Applications and are not covered by this
      License, and convey such a combined library under terms of your
      choice, if you do both of the following:

         a) Accompany the combined library with a copy of the same work based
         on the Library, uncombined with any other library facilities,
         conveyed under the terms of this License.

         b) Give prominent notice with the combined library that part of it
         is a work based on the Library, and explaining where to find the
         accompanying uncombined form of the same work.

        6. Revised Versions of the GNU Lesser General Public License.

        The Free Software Foundation may publish revised and/or new versions
      of the GNU Lesser General Public License from time to time. Such new
      versions will be similar in spirit to the present version, but may
      differ in detail to address new problems or concerns.

        Each version is given a distinguishing version number. If the
      Library as you received it specifies that a certain numbered version
      of the GNU Lesser General Public License "or any later version"
      applies to it, you have the option of following the terms and
      conditions either of that published version or of any later version
      published by the Free Software Foundation. If the Library as you
      received it does not specify a version number of the GNU Lesser
      General Public License, you may choose any version of the GNU Lesser
      General Public License ever published by the Free Software Foundation.

        If the Library as you received it specifies that a proxy can decide
      whether future versions of the GNU Lesser General Public License shall
      apply, that proxy's public statement of acceptance of any version is
      permanent authorization for you to choose that version for the
      Library.