DiscoCheck is a free UCI chess engine. It is not a complete chess program and requires a UCI compatible interface to be used comfortably. You can also use it directly in command line, but that is only of interest for programmers.
DiscoCheck has the following UCI options
- Hash (MB): size of the main hash table.
- Clear Hash (button): clears the hash table.
- Contempt (cp): Make DiscoCheck avoid draws (by chess rules) by scoring them -Contempt for the engine and +Contempt for the opponent.
On Linux (or POSIX), with g++ installed, simply run ./make.sh to compile.
On Windows, and/or with other compilers (eg. MSVC, ICC), I don't know. So you will have to figure it out. That being said, I have tried hard to write code as portable as possible, but there may be a few things that are GCC specific. If you find something that is not portable and should be rewritten to improve portability, please let me know (patches and pull requests are welcome).
DiscoCheck is free, and distributed under the GNU General Public License (GPL). Essentially, this means that you are free to do almost exactly what you want with the program, including distributing it among your friends, making it available for download from your web site, selling it (either by itself or as part of some bigger software package), or using it as the starting point for a software project of your own.
The only real limitation is that whenever you distribute DiscoCheck in some way, you must always include the full source code, or a pointer to where the source code can be found, as well as the GPL license agreement included with it. If you make any changes to the source code, these changes must also be made available under the GPL.
For full details, read the copy of the GPL found in the file named ./license.