lutz
17th February 2011, 23:46
Hello,
I am brand new Qt, and just finished writing my first small app. Even though it's fairly trivial and probably not useful for very many people, I would like to make it available for download on my website under the GPL license.
While the technical documentation is excellent, I find the legal details of the various licensing options very confusing. While I understand that this forum is not the best place to get legal advice, I would very much appreciate any feedback on the following questions.
Qt is available under different open source licenses, LGPL 2.1 and GPL 3.0. How do I know which one I am using? This Nokia FAQ (http://qt.nokia.com/about/licensing/frequently-asked-questions#can-i-switch-from-1) makes it sound like there are two separate versions of Qt corresponding to the two licenses:
Can I switch from using Qt under the GPL to the LGPL?
No, those using the GPL-licensed versions of Qt need to fulfill the requirements of the GPL. You will be able to re-release your work under the LGPL by incorporating it with or using the LGPL licensed version of Qt.
I do not recall ever choosing between these two licenses.
If I distribute only the source code of my program, am I bound by any of Qt's license agreements? Does the fact that I edited my code in Qt Creator, and designed my forms in Qt Designer, cause the code itself to fall under either the LGPL or GPL license?
If I distribute only the source code under the GPL, do I still have to include in the code the attribution statements to Nokia? Do I have to provide functionality that these attributions are accessible to an end user of the compiled program, for example in the "About App" box?
I would also like to distribute the application in binary form, for example as a Mac application bundle. This bundle includes the compiled Qt libraries the will be linked to dynamically. What are my additional obligations in this scenario? I assume that I will have to include the LGPL license text in the bundle, if I use the Qt libraries under that license. In this case, does the application need an end-user accessible function that displays the Qt attribution? Do I have to link to the Qt source code, either from the application itself, or from the website where I distribute my program?
I apologize for this long list of questions. Since I want to make my program available under the GPL, I would have thought that this would be the easiest case. I wish Nokia made available some examples for open source applications that exemplify the legal requirements.
Thank you for your interest,
Lutz
I am brand new Qt, and just finished writing my first small app. Even though it's fairly trivial and probably not useful for very many people, I would like to make it available for download on my website under the GPL license.
While the technical documentation is excellent, I find the legal details of the various licensing options very confusing. While I understand that this forum is not the best place to get legal advice, I would very much appreciate any feedback on the following questions.
Qt is available under different open source licenses, LGPL 2.1 and GPL 3.0. How do I know which one I am using? This Nokia FAQ (http://qt.nokia.com/about/licensing/frequently-asked-questions#can-i-switch-from-1) makes it sound like there are two separate versions of Qt corresponding to the two licenses:
Can I switch from using Qt under the GPL to the LGPL?
No, those using the GPL-licensed versions of Qt need to fulfill the requirements of the GPL. You will be able to re-release your work under the LGPL by incorporating it with or using the LGPL licensed version of Qt.
I do not recall ever choosing between these two licenses.
If I distribute only the source code of my program, am I bound by any of Qt's license agreements? Does the fact that I edited my code in Qt Creator, and designed my forms in Qt Designer, cause the code itself to fall under either the LGPL or GPL license?
If I distribute only the source code under the GPL, do I still have to include in the code the attribution statements to Nokia? Do I have to provide functionality that these attributions are accessible to an end user of the compiled program, for example in the "About App" box?
I would also like to distribute the application in binary form, for example as a Mac application bundle. This bundle includes the compiled Qt libraries the will be linked to dynamically. What are my additional obligations in this scenario? I assume that I will have to include the LGPL license text in the bundle, if I use the Qt libraries under that license. In this case, does the application need an end-user accessible function that displays the Qt attribution? Do I have to link to the Qt source code, either from the application itself, or from the website where I distribute my program?
I apologize for this long list of questions. Since I want to make my program available under the GPL, I would have thought that this would be the easiest case. I wish Nokia made available some examples for open source applications that exemplify the legal requirements.
Thank you for your interest,
Lutz