c++ – How to correctly set the LGPL license for a Qt release program?


I just want to know if I'm right. Let's say I created a release exe file, placed the necessary Qt libraries to run in a folder. The program is licensed under the LGPL. I throw the license file LICENSE.txt with a description of the license http://www.gnu.org/licenses/lgpl.html into the program folder.

  1. Is this enough to distribute the program?
  2. I want to add my own conditions additionally, for example: "You use this software at your own peril and risk. The author is not responsible for possible undesirable consequences in case of using this software." Well, I also want to write something like that access to your file system will not be used by hackers, etc. Of course, I will translate everything into English. So generally right?
  3. And Inno Setup make an installer with this license file.


Is this enough to distribute the program?

Not enough. Briefly on points:

  1. Qt does not use LGPL , but LGPLv3 – this is important!
  2. According to clause 4 LGPLv3 , in addition to placing the text of the original (without translation) license, you need to add a link/clause to the executable file that mentions the use of the library and the license, as well as a link/clause where the text of the license will be available from the application . This is usually done in the "About" dialog. And it’s better to independently study this clause of the license and fulfill all its requirements, there are not many of them.
  3. You can distribute the program under several licenses at the same time, for example, LGPLv3 and your own. But be aware that you must ensure that there are no license conflicts. In other words, there should not be a single mutually exclusive requirement between all licenses at the same time. However, you have the right to prohibit assumptions from other licenses (to impose your own non-contradictory requirements).

Of course, I will translate everything into English

You are free to leave your license in any language. But there is a nuance. Only a license in one language (this is the original) is considered a valid license. What language it will be is up to you.

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