gnuchess

gnuchess [options]

-?
    Display help and exit.

--help
    Display help and exit.

-v
    Display version and exit.

--version
    Display version and exit.

-f <file>
    Read commands from file.

--file <file>
    Read commands from file.

-e <command>
    Execute a command.

--eval <command>
    Execute a command.

-d <depth>
    Set the search depth to depth.

--depth <depth>
    Set the search depth to depth.

-m <moves>
    Set the number of moves to analyze to moves.

--moves <moves>
    Set the number of moves to analyze to moves.

-s <seconds>
    Set the time limit per move to seconds.

--seconds <seconds>
    Set the time limit per move to seconds.

-l <level>
    Set skill level (0-20).

--level <level>
    Set skill level (0-20).

--variant <variant>
    Set chess variant (e.g., normal, suicide, loser).

--uci
    Use UCI protocol for communication.

GNU Chess is a free, command-line chess program. It provides a chess engine that can be used by other chess programs or played directly from the command line. It supports various chess variants and can be configured with different levels of strength. It's primarily used for playing chess, analyzing positions, and testing chess interfaces. The user interacts through a text-based interface or via a GUI if coupled with another program that handles the graphical display. The chess engine calculates moves based on configurable search depth and heuristics to determine the best move.

It doesn't have a built in graphical display so external tools are needed to show the chessboard to the user. The command provides an interface to a chess engine.

GNU Chess is primarily an engine. You'll need a separate GUI (like XBoard, Arena, or similar) to interact with it graphically. The command-line interface is primarily for debugging and advanced users.

To play a game, you usually start `gnuchess` with a GUI. The GUI allows you to see the board and make moves with the mouse. The GUI will communicate the moves to `gnuchess`, and `gnuchess` will respond with its moves.

UCI (Universal Chess Interface) is a standard protocol used by chess engines to communicate with GUIs. Using the `--uci` option allows gnuchess to communicate with modern GUIs. UCI protocol usage is the recommended approach to run GNU Chess.

GNU Chess was created as a free software chess engine. It has been continually developed and improved over several decades. Its focus has always been on being a robust and portable chess engine, capable of running on a variety of platforms.

Early versions used simpler evaluation functions and search algorithms, but as computing power increased, so did the complexity and sophistication of the engine. It has played a significant role in the open-source chess community, serving as a foundation for many other chess programs and interfaces.

xboard(1), stockfish(1)