skeinsum is an implementation of version 1.3 of the Skein cryptographic hash function. It is licensed under version 3 of the GNU General Public License or, at your option, any later version. See COPYING for details. First run autoreconf --install; then see the INSTALL file for installation information. Once the software is installed, invoke skein256sum, skein512sum, or skein1024sum with the --help option to see usage information. The skeinsum home page is http://jxself.org/skein.shtml. Information about the Skein cryptographic hash function itself is available at http://www.skein-hash.info/