What happens if I load the GPL library using Qt's QPluginLoader?
-
I am using Qt commercial license.
Qt can use the *.so libraries loaded via the QPluginLoader.
If I load the GPL v2 library through QPluginLoader in my program, will my program become GPL v2?
My program is not a GPL because my program is not a dynamic link with the GPL library?
I'm sorry I don't have enough English.
-
Hi,
IIRC, that's more complicated than that. You should ask a lawyer or at least contact the fsfe to get their opinion on that.
-
It should be fine - plugin (by it's very nature) is loaded dynamically, so it is clearly a separate entity and should not force any license on your code.
(I'm not a lawyer, though, I may be wrong about it)
@sierdzio I don't think FSF will agree with you. If you load a lib at runtime it is executed in your process and "extends" it - I'm quite sure FSF sees this as "derived work".
-
@sierdzio I don't think FSF will agree with you. If you load a lib at runtime it is executed in your process and "extends" it - I'm quite sure FSF sees this as "derived work".
@jsulm said in What happens if I load the GPL library using Qt's QPluginLoader?:
@sierdzio I don't think FSF will agree with you. If you load a lib at runtime it is executed in your process and "extends" it - I'm quite sure FSF sees this as "derived work".
Possibly. That's why it's very good that Sam recommended getting in touch with them.
I'd definitely agree that modifying the plugin in question requires it to also be distributed under GPL.
However, loading the plugin - in my view - does not require the project to adopt GPL. It's very similar to running a command on the command line - you are using a program, and it will modify the outcome of your script, but it does not violate GPL nor your freedoms. You can always decide to load a different plugin / run a different command that does the same work.
(Z(:^
-
@jsulm said in What happens if I load the GPL library using Qt's QPluginLoader?:
@sierdzio I don't think FSF will agree with you. If you load a lib at runtime it is executed in your process and "extends" it - I'm quite sure FSF sees this as "derived work".
Possibly. That's why it's very good that Sam recommended getting in touch with them.
I'd definitely agree that modifying the plugin in question requires it to also be distributed under GPL.
However, loading the plugin - in my view - does not require the project to adopt GPL. It's very similar to running a command on the command line - you are using a program, and it will modify the outcome of your script, but it does not violate GPL nor your freedoms. You can always decide to load a different plugin / run a different command that does the same work.
@sierdzio See https://www.gnu.org/licenses/gpl-faq.en.html#NFUseGPLPlugins
and https://www.gnu.org/licenses/gpl-faq.en.html#GPLPlugins
Especially:
"If the main program dynamically links plug-ins, and they make function calls to each other and share data structures, we believe they form a single combined program, which must be treated as an extension of both the main program and the plug-ins."
They talk about dynamic linking, not loading at runtime, so I'm not sure what they think about loading at runtime.
Asking a lawyer as a good idea :-) -
OK that sounds like I was wrong :-)
