4.3BSD-Tahoe/usr/man/cat6/gnuchess.0
ADVENTURE(6) UNIX Programmer's Manual ADVENTURE(6)
NNAAMMEE
gnuchess - The Technology Chess Program for GNU Unix
SSYYNNOOPPSSIISS
ggnnuucchheessss [ --nn ]
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_C_h_e_s_s plays a game of chess against the user. Or it plays
against itself. Or it referees a game.
_C_h_e_s_s has two display modes. The first mode is simply a nor-
mal mode that you could use with a terminal. The second mode
is a fancy display mode you can use with a SUN workstation.
To use the former, simply type 'gnuchess'. To use the
latter, simply type 'chesstool gnuchess' on a SUN worksta-
tion where 'chesstool' is installed. In the latter example,
the argument should be the path specifying where to find the
gnuchess binary.
The following documentation assumes you are in the first
mode (e.g. normal mode using a regular terminal). If not,
then you should read the chesstool documentation.
For help once in _C_h_e_s_s type a question-mark. To type in your
move, use the notation "e2e4" where the first letter-number
pair indicates the origination square and the second
letter-number pair indicates the destination square. The
letter indicates the column with the left-most column being
"a" and the right-most column being "h". The number indi-
cates the row, the first row (White's first rank) being "1"
and the last row (Black's first rank) being "8". To castle,
type the origin square of the king and the destination
square of the king, just as you would do for a regular move.
The "bd" command prints what the current board position
looks like. You may type this to see what the board looks
like after the computer moves.
The "book" command compiles the opening book into dbm(3)
format. This book is then consulted whenever the computer
makes a move. If the current position is in the book, then
the suggested move associated with that position will be
made as the computer's move. Note that this command is a
maintenance command, usually used only once per site per
book.
The "depth" command allows the user to change how many moves
ahead the computer looks. Normally, it looks ahead three
half-moves, examining every move for each side. Then, it
examines all captures for both sides for another two half-
moves. "Depth" changes the first of these values. There is
an upper boundary of five half-moves as set by the
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quiescence search which searches captures a little deeper to
get better tactical play.
The "enter" command causes the current game played thus far
to be entered in the human-readable version of the opening
book. If no current game is in progress, this command
requests the name of a file from which to read games. These
are then added to the binary database. Since the versions
of the two files are slightly different, in the former case,
you must additionally type "book" to get the new game fully
entered in the book. Also, the "enter" command tries to
mail your new additions to the book maintainers so that your
contributions can be added to the master copy of the book.
If you are not on our network, you should send us your new
additions via some other method.
"Fill" allows the user to specify a completely different
board position. Input is based on Forsythe notation. For
example, the opening position in Forsythe notation is
"rnbqkbnrpppppppp8888PPPPPPPPRNBQKBNR+". Capital letters
indicate a White piece, lower-case Black. A plus means it is
White's move, a minus means Black's.
"History" and "historyf" list the game as played so far to
the terminal and a file respectively. The file is assumed to
be "GAMES/chXXXXXX" where XXXXXX is a random number and
GAMES is a subdirectory. If GAMES does not exist, an error
message is reported. The equivalent of "historyf" is done
after every move automatically to record the game thus far.
"Legals" shows legal moves for the current position along
with the rating for each move based on a positional presort.
"Neither" instructs the program to play neither side, that
is, to simply act as a referee.
"Reset" resets the board to the starting position.
"Quit" exits the game.
"Read" restores a game as if you were still playing it. The
game must be in the format as written by "historyf" or as
automatically recorded by the program itself after every
move.
"Self" causes the program to play against itself.
"Static" causes a static evaluation to be done for the
current position. A static evaluation is based on material
difference only. Positional considerations are handled by
the ply-1 positional presort.
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"Switch" causes the program to move, whether or not it is
the program's turn to do so. Continually typing "switch" is
equivalent to typing "self".
"Test-moves" initiates a test of the speed of the move gen-
erator. An initial series of move generations is done for
the opening position and the timing speed is reported.
Then, for each of ten stored test positions, a series of
move generations is done and the timing speed is reported
for each one. Finally, the program averages across those ten
runs and reports the overall average.
"Test-search" uses the ten stored test positions to actually
conduct a search at the current depth to choose a move for
each position.
"Undo" undoes the last move whether it was the computer's or
the human's. You may also type "remove". This is equivalent
to two "undo's" (e.g. retract one move for each side).
The flag-option on the command line allows specification of
how deep to search in half-moves as with 'Chess -3' to
search three half-moves ahead. Capture searches are normally
carried out a few half-moves further than the regular full
search specified with this option. This is known as the
quiescence search and it usually is conducted to 6 ply. This
option is identical to the "depth" command once in the pro-
gram.
BBUUGGSS
En passant is not currently implemented. Also, promotion to
pieces other than queens is disallowed. Checks and check-
mates are not detected in the tree-search and are not han-
dled as "forcing" variations.
There are other bugs. Suggestions for improvements and
caveats are contained in the files README and TODO which
come with this distribution.
AAUUTTHHOORR
Stuart Cracraft Stuart Cracraft
P.O. Box 13123 UCLA, Dept. of Mathematics
Torrance, Ca. Los Angeles, Ca.
90503 90024
(213) 214-1136 (213) 825-9040
AAUUTTHHOORR''SS CCOOMMMMEENNTT
This software is being made available by the Free Software
Foundation under the restrictions described in its license
agreement which accompanies this distribution. This
software, its sources, binaries, documentation and all asso-
ciated parts are copyright (C) 1986 by the Free Software
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ADVENTURE(6) UNIX Programmer's Manual ADVENTURE(6)
Foundation, Inc.
SSEEEE AALLSSOO
chesstool(6)
dbm(3)
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