The Q Public License (QPL) is a non-
copyleft license, created by
Trolltech for its
free
Free may refer to:
Concept
* Freedom, having the ability to do something, without having to obey anyone/anything
* Freethought, a position that beliefs should be formed only on the basis of logic, reason, and empiricism
* Emancipate, to procur ...
edition of the
Qt. It was used until Qt 3.0, as Trolltech toolkit version 4.0 was released under GPL version 2.
It fails the
Debian Free Software Guidelines,
used by several
Linux distributions, though it qualifies for the Free Software Foundation's
Free Software Definition; however, it is not compatible with the FSF's
GNU General Public License,
meaning that products derived from code under both the GPL and the QPL cannot be redistributed.
History
KDE
KDE is an international Free software movement, free software community that develops free and open-source software. As a central development hub, it provides tools and resources that allow collaborative work on this kind of software. Well-know ...
, a
desktop environment for
Linux, is based on Qt. Only the free open source edition of Qt was covered by the QPL; the commercial edition, which is functionally equal, is under a pay-per-use license and could not be freely distributed. Meanwhile, the
Free Software Foundation and authors of the GPL objected to the QPL as it was a non-copyleft license incompatible with the GPL.
As KDE grew in popularity, the
free software community urged Trolltech to license Qt under the GPL to ensure that it would remain free software forever and could be used and developed by commercial third parties. Eventually, under pressure, Trolltech dual-licensed the free edition of Qt 2.2 for use under the terms of the GPL or the QPL.
Adoption
Other projects that have adopted the Q Public License, sometimes with a change in the choice of jurisdiction clause, include:
* LibreSource is a versatile collaborative platform provided by
artenum and dedicated to collaborative software development
* Jpgraph is a graph generation tool written in PHP that dynamically produces charts and graphs as image files for presentation on websites.
*
Hercules, a software implementation of the
System/370,
ESA/390
The IBM System/390 is a discontinued mainframe product family implementing the ESA/390, the fifth generation of the System/360 instruction set architecture. The first computers to use the ESA/390 were the Enterprise System/9000 (ES/9000) ...
, and
z/Architecture
z/Architecture, initially and briefly called ESA Modal Extensions (ESAME), is IBM's 64-bit complex instruction set computer (CISC) instruction set architecture, implemented by its mainframe computers. IBM introduced its first z/Architecture-b ...
mainframe computer architectures.
*
Tgif switched from a free-of-charge non-commercial license to the Q Public License.
Previous projects using the Q Public License include:
* The
OCaml
OCaml ( , formerly Objective Caml) is a general-purpose programming language, general-purpose, multi-paradigm programming language which extends the Caml dialect of ML (programming language), ML with object-oriented programming, object-oriented ...
compiler and related tools from Projet Cristal at
INRIA. Since April 2016 OCaml is released under the
GNU Lesser General Public License version 2.1 with linking exception.
*
CGAL
The Computational Geometry Algorithms Library (CGAL) is an open source software library of computational geometry algorithms. While primarily written in C++, Scilab bindings and bindings generated with SWIG (supporting Python and Java for now) ar ...
for versions 3.x. The CGAL library is released under
GNU General Public License/LGPL since CGAL version 4.0 (March 2012).
The
Debian
Debian (), also known as Debian GNU/Linux, is a Linux distribution composed of free and open-source software, developed by the community-supported Debian Project, which was established by Ian Murdock on August 16, 1993. The first version of D ...
project rejects software covered by solely QPL
(and not dual licensed with something else like the GPL) because of:
* A forum selection clause, choice of venue clause
* Forced distribution to a third party
* Forced blanket license to the original developer
Compliance
All legal disputes about the license are settled in Oslo, Norway,
but it has never been legally contested.
See also
* Open source license
References
External links
The Q Public License, version 1.0
{{Qt
Free and open-source software licenses
Qt (software)
