Do i need to host qt source when compling with lgplv3 license. Newest lgpl questions software engineering stack exchange. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. Examples of multilicensed software include oracles netbeans ide, mysql abs database, asterisk, oracle. Most of qt is available under lgpl, but some modules are gpl only. Using python module on lgpl license in commercial product closed ask question asked 7 years. Lgpl is a copyleft open source software license that is less.
These examples in the previous slides are not exhaustive. This is at least the stated goal of the qt company. Does this also applies to embedded device which will be used to measure for example presure in. The commercial qt license gives you the full rights to create and distribute software on your own terms without any open source license obligations. The qt commercial developer license does not allow the incorporation of code developed with the qt gnu lgpl v. Besides the lgpl license for pyside2, youll have to make sure that you comply with the qt licensing terms. The free software foundation may publish revised andor new versions of the gnu lesser general public license from time to time. Qt licensed under the gnu lesser general public license lgpl version 3 is appropriate for the development of qt applications provided you can.
However you must license qt under the lgpl and discharge your responsibilities under that. Its not permitted to mix qt commercial licenses with qt lgpl licenses in one project. With the commercial license you also have access to the official qt support and close strategic relationship with the qt company to make sure your development goals are met. If you choose to use the qt library under the opensource lgpl license, you may either. See how to choose a license for your own work for general recommendations about choosing a license for your work the gnu project has two principal licenses to use for libraries. I have heard too many conflicting sayings on qt licensing which confused me a lot. Just keep in mind that you are not supposed to bundle free software with nonfree software, so. Although we refer to pyqt specifically the same answers apply to all software licensed under the. Qt commercial includes a source license that allows you to change the code, link statically, and not distribute your changes. I worked for trolltech, and then later nokia who bought t. The documentation provided herein is licensed under the terms of the gnu free documentation license version 1.
Can i use an lgpllicenced library in my commercial app. Using python module on lgpl license in commercial product. Additionally, the examples included with qt are provided under the terms of the. Can someone give me a simple explanation on qt licenses and tell me if i can sell my application without any kind of restrictions at all or not. The following table lists parts of qt that incorporate code licensed. And, if you deploy your qt application on an embedded device, you.
Qt contains some code that is not provided under the gnu lesser general public license lgpl or the qt commercial license, but rather under specific licenses from the original authors the qt company gratefully acknowledges these and other contributions to qt. No, you must buy a pyqt commercial license for commercial use. So im remaking a product and was approaching qt about the commercial version. Can i develop with commercial qt and install qt creator to more than one of my computers. It means that if you use a software component licensed under lgpl v3 you have to provide the users the possibility to replace this components with their own. So do take all these answers with a grain of salt, because otherwise you may be exposing yourself to lawsuits. In this scenario, one option is a proprietary software license, which allows the possibility of creating proprietary. Ive been reading about qt and its licensing and ive come across this part. Qt is available under different licensing options designed to accommodate the needs of our various users. When selecting an open source license for your project, you contribute to free and open source software development by using qt under any of the following licenses. The qt legal faq does which isnt the same as the license. I also do not see every single project that uses lgpl software doing so for their sources actually most do not and point to the original provider in most cases, strictly talking dynamically linked and nonmodified source g19fanatic feb 14 16 at.
So that makes qt pretty unattractive to me since i have to pony up cash and hope its good. We recommend that programs that use qt also acknowledge these contributions, and quote these license statements in an appendix to the. The rep was very insistent that i can not develop an internal prototype using the open source license and then move to the commercial license. Qt pronounced cute is a free and opensource widget toolkit for creating graphical user. Qt for device creation is a product available only under a commercial license. I mean, if you dont need to modify the qtlibrary, you dont need commercial license. However, the qt situation does not involve the revocation or threat of revocation of a license. This comes from the same company as qt itself, and is licensed under gpllgpl commercial, also the same as. If you use qt under commercial license, nothing has changed for you. Qt lgpl license query for embedded system qt lgpl license query for embedded system. Qt moving from lgpl to commercial halfway through closed.
Lesser general public license is sometimes referred to as library gpl or gnu libraries, and some associate it with the idea of. A possible alternative is to switch to pyside2, also known as qt for python. Gnu lesser general public license usage alternatively, this file may be used under the terms of the gnu lesser general public license version 2. Then the info page of the application should explicitly show the qt. I dont have enough money to buy commercial license. The following table lists parts of qt that incorporate code licensed under licenses other than gnu lesser general public license lgpl or the commercial license, as well as qt modules that are only available under a specific license or a version of a license. Qt documentation is available under commercial licenses from the qt company, and under the terms of the gnu free documentation license fdl version 1. As the qt legal gal i receive numerous questions from companies looking to use qt, wanting to know which license makes the most sense for them. Qt commercial license agreements is available in the qt licensing overview.
Qt examples are available under commercial licenses from the qt company, and under a bsd3clause license. Some customers use commercial qt and thus pay the qt company per runtime license, and some use the opensource version and dont pay. Is this something applicable to all commercial software using gpllgpl components. Free and open source software foss is software that comes with a license that. However you must license qt under the lgpl and discharge your responsibilities under that license. Can i use the opensource qt license in a commercial project. Documentation contributions included herein are the s of their respective owners. The example of gladarius is valid for yout software only and if you release your software as commercial nonfree you should state the corresponding license you want. Audacious free and opensource audio player software. Many of our customers use qt, which is a great product for embedded gui creation, and indeed we supply qt ready arm linux builds to help them. Most commercial software comply simply by dynamically linking to qt. If you choose to use the qt library under the opensource lgpl license, you may either statically or dynamically link it.
Lgpl which qt is released allows commercial closed source applications as long as you do not modify the qt libraries or if you do making them available to. A lesser general public license lgpl is a license for opensource software that allows for provisions for including elements of free software in either free or proprietary software. At qt day 2019 in florence, italy, i gave a presentation about using qt under lgplv3. The qt company has announced that the availability of future versions under the gpl will be limited.
Qt is available under the following free software licenses. A collection of modular, scalable, secure software libraries, development tools and interoperability protocols geared to make automation software development with qt even more cost and timeefficient. So im remaking a product and was approaching qt about the. The qt software uses a duallicensing model, offering both proprietary and gpl licenses to the framework. If you intend to develop software using the qt framework, you will need a license commercial or open source. Here we use the term proprietary application to mean any application that is distributed under the terms of a license that is not compatible with the relevant version of the gpl and has been developed using a copy of any sofware licensed under the riverbank commercial license. With the commercial license you also have access to the official qt support and close strategic relationship with the qt. Some say that even if i use lgpl version of qt, i still need to submit my code. I will distribute with my app such libraries as qtcore4. Qt examples are available under commercial licenses from the qt company, and under a. There is written in lgpl license that i can use not modified, linked code in commercial, closed product without changing license of product to lgpl. Qt lgpl license query for embedded system qt forum.
Even modules like the virtual keyboard, the software renderer for qml without opengl and the unittest integration into qtcreator will become available under gpl. Multilicensing is the practice of distributing software under two or more different sets of terms. The thing is, pyside2 is for using the qt framework with python programs. I need to use qt and i choose to use lgpl license for qt in my app. If you are making an application under a different license for example, a commercial application, you have to be careful to meet the requirements of lgpl andor gpl.
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