I have read many articles about GPL because many libraries are using it and I use some of them inside a personal application I made.

After testing my application I am thinking of making it public. It`s free of charge (freeware) and the problem is that I use a library as an external executable that is run by my application. This external executable is on GPL license but my application is not (and does not use any GPL-licensed library within it).

Here are some links I read about the GPL license :

Why the gpl is not free

Are you sure you want to use GPL

Why not to use GPL and any GPL type license !

I do understand that anyone who uses a lib under GPL has to make his application open source, but I don`t know if I have to make just the executable that is under GPL license open source or if I have to make my application (which is not under the GPL licence) open source too?

Also I read that if an application is under GPL license you can`t use your own license and terms and conditions. Does this apply only to the GPL exe? or also to my exe which is not GPL?

  • Also see OpenSource Stackexchange. This post may answer your question: Shipping GPL'd binaries in commercial product. Since you are not planning to distrbute your program's source code, it is equivalent to a "commercial program" for the purpose of the GPL, even if you release it without charge. – Brandin Nov 23 '17 at 15:45

The core misunderstanding you have is hinted at by the question in your last paragraph.

Forget "open source", there are (sadly) many hundred open source licences. The GPL requires that any "derivative work" of GPL licensed code must also be licensed under the GPL if it is distributed.

So the question is, does an application which runs an executable created from GPL licensed code constitute "a derivative work"? I am not a lawyer (and in particular, I am not an intellectual property lawyer), but I don't think it does. Therefore you can distribute the GPL'ed executable, and your own application without having to license your application under the GPL.

If you make any modifications to the GPL'ed library to support your application, you must GPL those modifications, and hence you must distribute the source to those modifications (a link to Github would probably be sufficient).

  • Thanks for the edit and the reply. So by using the GPL executable from my application if i go public and can be downloaded and used by others also i will only have to Github the code of the executable that was using GPL license and not my entire application if i understood well ? – Vas Nov 23 '17 at 11:22
  • Yup, that's about right. Incidentally, of those three GPL links the last strikes me as an extremely poorly thought-through rant. The second is a reasonable discussion of the difference between GPL and MIT-like licenses. The first strikes me as unconvincing. All three are discussing the differences between different types of open source license. As I understand it, you want to keep your source secret, so none of them apply to your case. – Martin Bonner Nov 23 '17 at 11:29
  • That links have their own way of thinking but i do appreciate them now that i can clearly see wha's going on with licenses in softwares. Yes my application is closed source free software but at least if i only need to make the external exe as open source and not the entire application would be kind of fine though i wouldn't like it too.Whatever... since that's the way this license work, i will only use the GPL'ed exe as open source to github with a GPL license as the ones i used it from had and will be fine. Thank you Martin – Vas Nov 23 '17 at 11:36

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.