


gnuchess(6)                                           gnuchess(6)


NNAAMMEE
       gnuchess - Chess

SSYYNNOOPPSSIISS
       ggnnuucchheessss [ [[[[--]]aa]] [[--bb bbooookkffiillee]] [[--BB bbiinnbbooookkffiillee]] [[--hh llaanngg--
       ffiillee]] [[--LL llaannggffiillee]] [[--rr lleennggtthh]] [[--ss  ppaatthhnnaammee]]  [[--ll  ppaatthh--
       nnaammee]]  [[--SS bbiinnbbooookkssiizzee]] [[--tt]] [[--cc ssiizzee]] [[--TT ssiizzee]] [[--vv]] [[--xx]]
       aarrgg11 aarrgg22 ]

DDEESSCCRRIIPPTTIIOONN
       _G_n_u_c_h_e_s_s plays a game of chess  against  the  user  or  it
       plays against itself.

       _G_n_u_c_h_e_s_s  is  an  updated version of the GNU chess playing
       program.  It has a simple alpha-numeric board display,  an
       IBM PC compatible interface, or it can be compiled for use
       with the cchheessssttooooll program on a SUN  workstation  or  with
       the xxbbooaarrdd program under X-windows.  To invoke the program
       type:

       ggnnuucchheessss
              - simple curses based version

       ggnnuucchheessssnn
              - fancy version using curses and inverse  video  on
              UNIX,  or  IBM PC cursor controls and characters on
              MSDOS

       ggnnuucchheessssrr
              - ASCII based version

       ggnnuucchheesssscc
              - chesstool compatible version

       ggnnuucchheessssxx
              - xboard compatible version

TTIIMMEE CCOONNTTRROOLLSS
       If one argument is given, it is the search time  per  move
       in  [minutes:]seconds.   So  ggnnuucchheessss 3300 will generate one
       move every 30 seconds, while ggnnuucchheessss 55::0000  will  generate
       one move every 5 minutes.

       If  two  or more arguments are given, they will be used to
       set tournament time controls with the  first  argument  of
       each  pair  being the number of moves and the second being
       the total clock time in minutes[:seconds].  Thus, entering
       ggnnuucchheessss  6600 55 will set the clocks for 5 minutes (300 sec-
       onds) for the first 60 moves, and ggnnuucchheessss  3300  33::3300  will
       allow 3 minutes and 30 seconds for 30 moves.

       ggnnuucchheessss  3300 55 11 ::3300 will allow 5 minutes for the first 30
       moves and 30 seconds for each move after that.   Up  to  4
       pairs of controls may be specified.



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gnuchess(6)                                           gnuchess(6)


       If  no  argument is given the program will prompt the user
       for level of play.

       For use with cchheessssttooooll or xxbbooaarrdd,, see the documentation on
       those programs.

BBOOOOKK
       At  startup  _G_n_u_c_h_e_s_s reads the _b_i_n_b_o_o_k file if it is pre-
       sent. It then looks for a _b_o_o_k file. If it is  present  it
       adds its contents to the _b_i_n_b_o_o_k data. If the _b_i_n_b_o_o_k file
       is writable a new combined _b_i_n_b_o_o_k file is written.

       The book _g_n_u_c_h_e_s_s_._b_o_o_k consists of a sequence of openings.
       An  opening  begins  with  a line starting with a !!  , the
       rest of the line is comments.  Following this is a  series
       of moves in algebraic notation alternating white and black
       separated by white space. A move may have a  ??   after  it
       indicating  this  move  should never be made in this posi-
       tion.  Moves are stored as position:move so transpositions
       between openings can take place.

HHAASSHHFFIILLEE
       The  hashfile  if  created  should  be  on  the order of 4
       megabytes or ggnnuucchheessss --cc 2222..  This file contains positions
       and  moves  learned from previous games.  If a hashfile is
       used the computer makes use of the experience it gained in
       past  games.  Tests run so far show that it plays no worse
       with the hashfile than without, but it is  not  clear  yet
       whether it provides a real advantage.

LLEEGGAALL MMOOVVEESS
       NNoottee::  Piece letters and legal castling notation is deter-
       mined by the language file.  What is specified here is the
       default English.

       Once  _g_n_u_c_h_e_s_s  is  invoked,  the program will display the
       board and prompt the user for a move. To enter a move, use
       the notation ee22ee44 where the first letter-number pair indi-
       cates the origination square and the second  letter-number
       pair  indicates the destination square.  An alternative is
       to use the notation nnff33 where the first  letter  indicates
       the  piece type (p,n,b,r,q,k).  To castle, type the origin
       and destination squares of the king just as you  would  do
       for  a  regular  move,  or  type  oo--oo  or 00--00 for kingside
       castling and oo--oo--oo or 00--00--00 for queenside.  To  promote  a
       pawn  append  the type of the new piece to the move, as in
       ee77ee88qq or cc77cc88rr..

FFUUNNCCTTIIOONN LLEETTTTEERRSS
       --LL llaanngg
              Use language _l_a_n_g _f_r_o_m _t_h_e _f_i_l_e ggnnuucchheessss..llaanngg..   If
              -L  is  not specified it uses the first language in
              the file.




                                                                2





gnuchess(6)                                           gnuchess(6)


       --aa     Do not search on opponents time.

       aa      Do search on opponents time.

       --bb bbooookkffiillee
              Use bookfile for opening book.

       --BB bbiinnbbooookkffiillee
              Use binbookfile for binary opening book.

       --SS ssiizzee
              Size of binbookfile for memory based and GDX books.
              For creating a binbookfile.

       --PP ppllyylleevveellss
              Number  of  plys to include in the binbookfile. For
              generating a binbookfile.

       --cc ssiizzee
              Create a new HASHFILE. File size is 2^size  entries
              of approximately 65 bytes.

       --hh     Do not use hashfile.

       hh      Do use hashfile.

       --ll ppaatthhnnaammee
              Pathname  of the loadfile use with the ggeett or xxggeett..

       --rr lleennggtthh
              Rehash length times in searching  entries for posi-
              tion in transposition table.

       --ss ppaatthhnnaammee
              Pathname of the save file to use with the ssaavvee com-
              mand.

       --tt     Show statistics for HASHFILE

       --TT ssiizzee
              Set the transposition table size to 2^size entries.

       --vv     Show version and patchlevel.

       --xx vvaalluuee
              Use vvaalluuee as the evaluation window xxwwnnddww..

CCOOMMMMAANNDDSS
       In  addition  to  legal  moves, the following commands are
       available as responses.  NNoottee:: command  names  are  deter-
       mined by the _l_a_n_g_u_a_g_e file and may vary with the implemen-
       tation. This is default English.

       aallgg -- allow algebraic input (not implemented)



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gnuchess(6)                                           gnuchess(6)


       AAwwiinnddooww -- change Alpha window (default score + 90)

       BBwwiinnddooww -- change Beta window (default score - 90)

       bbeeeepp -- causes the program to beep after each move.

       bbdd -- updates the current board position on the display.

       bbooookk -- turns off use of the opening library.

       bbootthh -- causes the computer to play both sides of a  chess
       game.

       bbllaacckk -- causes the computer to take the black pieces.  If
       the computer is to move  first  the  ggoo  command  must  be
       given.

       ccoooorrddss -- show coordinates on the display (visual only)

       ccoonntteemmpptt -- allows the value of _c_o_n_t_e_m_p_t to be modified.

       ddeebbuugg  --   asks  for a piece as color piece, as wb or bn,
       and shows its calculated value on each square.

       ddeebbuugglleevveell --  sets level of debugging output if  compiled
       with debug options.

       ddeepptthh -- allows the user to change the search depth of the
       program.  The maximum depth is 29 ply.  Normally the depth
       is  set to 29 and the computer terminates its search based
       on elapsed time rather than depth.  If  depth  is  set  to
       (say)  4 ply, the program will search until all moves have
       been examined to a depth of 4 ply (with extensions  up  to
       11  additional  ply for sequences of checks and captures).
       If you set a maximum time per move and also use the  depth
       command, the search will stop at the specified time or the
       specified depth, whichever comes first.

       eeaassyy -- toggles easy mode (thinking on opponents time)  on
       and  off.  The  default  is easy mode ON.  If easy mode is
       disabled, the keyboard is polled for input every so  often
       and  when  input  is seen the search is terminated. It may
       also be terminated with a _s_i_g_i_n_t_.

       eeddiitt -- allows the user to set up a board position.

            ## - command will clear the board.

            cc - toggle piece color.

            ..  - command will exit setup mode.

       ppbb33 - place a pawn on b3




                                                                4





gnuchess(6)                                           gnuchess(6)


       Pieces are entered by typing a  letter  (p,n,b,r,q,k)  for
       the piece followed by the coordinate.

       The usual warning about the _l_a_n_g_u_a_g_e _f_i_l_e applies.

       eexxiitt -- exits gnuchess.

       ffiirrsstt -- tells the computer to move first. Computer begins
       searching for a move.  (same as "go").

       ffoorrccee -- allows the user to enter moves for both sides. To
       get the program to play after a sequence of moves has been
       entered use the 'white' or  'black'  command  followed  by
       'go'.

       ggaammeeiinn -- toggles game mode time control. Assumes the time
       specified for time control is  the  time  for  a  complete
       game. Input with the level command should be the game time
       and the expected number of moves in a game.

       ggeett -- retrieves a  game  from  disk.   The  program  will
       prompt the user for a file name.

       hhaasshh -- use/don't use hashfile.

       hhaasshhddeepptthh  --  allows the user to change the minimum depth
       for using the hashfile and the number of  moves  from  the
       begining of the game to use it.

       hheellpp  --  displays a short description of the commands and
       the current status of options.

       ggoo -- tells the computer to move  first.  Computer  begins
       searching for a move.  (same as "first").

       hhiinntt  --  causes  the  program to supply the user with its
       predicted move.

       lleevveell -- allows the user to set time controls such  as  60
       moves  in  5 minutes etc.  In tournament mode, the program
       will vary the time it takes for each move depending on the
       situation.   If  easy  mode  is disabled (using the 'easy'
       command), the program will often  respond  with  its  move
       immediately, saving time on its clock for use later on.

       lliisstt  --  writes  the  game  moves  and some statistics on
       search depth, nodes, and time to the file 'chess.lst'.

       mmaatteerriiaall -- toggle material flag - draws on no  pawns  and
       both sides < rook

       MMwwppaawwnn,,  MMbbppaawwnn,, MMwwkknniigghhtt,, MMbbkknniigghhtt,, MMwwbbiisshhoopp,, MMbbbbiisshhoopp --
       print out static position evaluation table




                                                                5





gnuchess(6)                                           gnuchess(6)


       nneeww -- starts a new game.

       pp -- evaluates the board and shows  the  point  score  for
       each  piece.  The total score for a position is the sum of
       these individual piece scores.

       ppoosstt -- causes the program to display the principle varia-
       tion  and  the score during the search.  A score of 100 is
       equivalent to a 1 pawn advantage for the computer.

       qquuiitt -- exits the game.

       rraannddoomm -- causes the program to randomize its move  selec-
       tion slightly.

       rrccppttrr -- set recapture mode.

       rreemmoovvee  -- backout the last level for both sides. Equal to
       2 _u_n_d_o_'_s_.

       rreevveerrssee -- causes the board display to be reversed.   That
       is,  the  white  pieces  will now appear at the top of the
       board.

       rrvv -- reverse board display.

       sseettuupp -- Compatibility with Unix chess and the nchesstool.
       Set  up a board position.  Eight lines of eight characters
       are used to setup the board.  a8-h8  is  the  first  line.
       Black pieces are  represented  by  uppercase characters.

       ssttaarrss -- (gnuchessn only) add stars (*) to black pieces.

       ssaavvee -- saves a game to disk.  The program will prompt the
       user for a file name.

       sswwiittcchh -- causes the program to  switch  places  with  the
       opponent and begin searching.

       tteesstt  --  performs  some speed tests for MoveList and Cap-
       tureList generation, and  ScorePosition  position  scoring
       for the current board.

       ttiimmee  --  set  computers time remaining, intended for syn-
       chronizing clocks among multiple players.

       uunnddoo -- undoes the last move whether it was the computer's
       or the human's. You may also type "remove". This is equiv-
       alent to two "undo's" (e.g.  retract  one  move  for  each
       side).

       wwhhiittee -- causes the computer to take the white pieces.  If
       the computer is to move  first  the  ggoo  command  must  be
       given.



                                                                6





gnuchess(6)                                           gnuchess(6)


       xxggeett -- read an _x_b_o_a_r_d position file.

       xxwwnnddww  --  change  X  window. The window around alpha/beta
       used to determine whether the position should be scored or
       just estimated.

BBUUGGSS
SSEEEE AALLSSOO
       chesstool(6)
       xboard(6)















































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