XZ Utils Licensing ================== Different licenses apply to different files in this package. Here is a rough summary of which licenses apply to which parts of this package (but check the individual files to be sure!): - liblzma is in the public domain. - xz, xzdec, and lzmadec command line tools are in the public domain unless GNU getopt_long had to be compiled and linked in from the lib directory. The getopt_long code is under GNU LGPLv2.1+. - The scripts to grep, diff, and view compressed files have been adapted from gzip. These scripts and their documentation are under GNU GPLv2+. - All the documentation in the doc directory and most of the XZ Utils specific documentation files in other directories are in the public domain. Note: The JavaScript files (under the MIT license) have been removed from the Doxygen-generated HTML version of the liblzma API documentation. Doxygen itself is under the GNU GPL but the remaining files generated by Doxygen are not affected by the licenses used in Doxygen because Doxygen licensing has the following exception: "Documents produced by doxygen are derivative works derived from the input used in their production; they are not affected by this license." - Translated messages are in the public domain. - The build system contains public domain files, and files that are under GNU GPLv2+ or GNU GPLv3+. None of these files end up in the binaries being built. - Test files and test code in the tests directory, and debugging utilities in the debug directory are in the public domain. - The extra directory may contain public domain files, and files that are under various free software licenses. You can do whatever you want with the files that have been put into the public domain. If you find public domain legally problematic, take the previous sentence as a license grant. If you still find the lack of copyright legally problematic, you have too many lawyers. As usual, this software is provided "as is", without any warranty. If you copy significant amounts of public domain code from XZ Utils into your project, acknowledging this somewhere in your software is polite (especially if it is proprietary, non-free software), but naturally it is not legally required. Here is an example of a good notice to put into "about box" or into documentation: This software includes code from XZ Utils <https://tukaani.org/xz/>. The following license texts are included in the following files: - COPYING.LGPLv2.1: GNU Lesser General Public License version 2.1 - COPYING.GPLv2: GNU General Public License version 2 - COPYING.GPLv3: GNU General Public License version 3 Note that the toolchain (compiler, linker etc.) may add some code pieces that are copyrighted. Thus, it is possible that e.g. liblzma binary wouldn't actually be in the public domain in its entirety even though it contains no copyrighted code from the XZ Utils source package. If you have questions, don't hesitate to ask the author(s) for more information.