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 xboard(6)                           GNU                           xboard(6)
                                   $Date:



 NAME
      xboard - X graphical user interface for chess

 SYNOPSIS
      xboard [options]
      xboard -ics -icshost hostname [options]
      xboard -ncp [options]
      |pxboard
      cmail [options]


 DESCRIPTION
      XBoard is a graphical chessboard that can serve as a user interface to
      chess engines (such as GNU Chess), the Internet Chess Servers,
      electronic mail correspondence chess, or your own collection of saved
      games.

      This manual documents version 4.7.3 of XBoard.


 MAJOR MODES
      XBoard always runs in one of four major modes.  You select the major
      mode from the command line when you start up XBoard.


      xboard [options]
           As an interface to GNU Chess or another chess engine running on
           your machine, XBoard lets you play a game against the machine,
           set up arbitrary positions, force variations, watch a game
           between two chess engines, interactively analyze your stored
           games or set up and analyze arbitrary positions.  (Note: Not all
           chess engines support analysis.)

      xboard -ics -icshost hostname [options]
           As Internet Chess Server (ICS) interface, XBoard lets you play
           against other ICS users, observe games they are playing, or
           review games that have recently finished.  Most of the ICS "wild"
           chess variants are supported, including bughouse.

      xboard -ncp [options]
           XBoard can also be used simply as an electronic chessboard to
           play through games. It will read and write game files and allow
           you to play through variations manually. You can use it to browse
           games off the net or review games you have saved.  These features
           are also available in the other modes.

      |pxboard
           If you want to pipe games into XBoard, use the supplied shell
           script `pxboard'.  For example, from the news reader `xrn', find
           a message with one or more games in it, click the Save button,
           and type `|pxboard' as the file name.



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      cmail [options]
           As an interface to electronic mail correspondence chess, XBoard
           works with the cmail program. See CMail below for instructions.

 BASIC OPERATION
      To move a piece, you can drag it with the left mouse button, or you
      can click the left mouse button once on the piece, then once more on
      the destination square. In crazyhouse, bughouse or shogi you can drag
      and drop pieces to the board from the holdings squares displayed next
      to the board.

      Old behavior, where right-clicking a square brings up a menu where you
      can select what piece to drop on it can still be selected through the
      `Drop Menu' option.  Only in Edit Position mode right and middle
      clicking a square is still used to put a piece on it, and the piece to
      drop is selected by sweeping the mouse vertically with the button held
      down.

      The default function of the right mouse button in other modes is to
      display the position the chess program thinks it will end up in.
      While moving the mouse vertically with this button pressed XBoard will
      step through the principal variation to show how this position will be
      reached.  Lines of play displayed in the engine-output window, or PGN
      variations in the comment window can similarly be played out on the
      board, by right-clicking on them.  Only in Analysis mode, when you
      walk along a PV, releasing the mouse button will forward the game upto
      that point, like you entered all previous PV moves.  As the display of
      the PV in that case starts after the first move a simple right-click
      will play the move the engine indicates.

      In Analysis mode you can also make a move by grabbing the piece with a
      double-click of the left mouse button (or while keeping the Ctrl key
      pressed).  In this case the move you enter will not be played, but
      will be excluded from the analysis of the current position.  (Or
      included if it was already excluded; it is a toggle.) This only works
      for engines that support this feature.

      When connected to an ICS, it is possible to call up a graphical
      representation of players seeking a game in stead of the chess board,
      when the latter is not in use (i.e. when you are not playing or
      observing).  Left-clicking the display area will switch between this
      'seek graph' and the chess board.  Hovering the mouse pointer over a
      dot will show the details of the seek ad in the message field above
      the board.  Left-clicking the dot will challenge that player.  Right-
      clicking a dot will 'push it to the back', to reveal any dots that
      were hidden behind it.  Right-clicking off dots will refresh the
      graph.

      Most other XBoard commands are available from the menu bar. The most
      frequently used commands also have shortcut keys or on-screen buttons.
      These shortcut keystrokes are mostly non-printable characters.  Typing



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      a letter or digit while the board window has focus will bring up a
      type-in box with the typed letter already in it.  You can use that to
      type a move in siuations where it is your turn to enter a move, type a
      move number to call up the position after that move in the display,
      or, in Edit Position mode, type a FEN.  Some rarely used parameters
      can only be set through options on the command line used to invoke
      XBoard.

      XBoard uses a settings file, in which it can remember any changes to
      the settings that are made through menus or command-line options, so
      they will still apply when you restart XBoard for another session.
      The settings can be saved into this file automatically when XBoard
      exits, or on explicit request of the user.  The default name for the
      settings file is /etc/xboard/xboard.conf, but in a standard install
      this file is only used as a master settings file that determines the
      system-wide default settings, and defers reading and writing of user
      settings to a user-specific file like ~/.xboardrc in the user's home
      directory.

      When XBoard is iconized, its graphical icon is a white knight if it is
      White's turn to move, a black knight if it is Black's turn.


 MENUS, BUTTONS, AND KEYS
    File Menu
      New Game
           Resets XBoard and the chess engine to the beginning of a new
           chess game. The `Ctrl-N' key is a keyboard equivalent. In
           Internet Chess Server mode, clears the current state of XBoard,
           then resynchronizes with the ICS by sending a refresh command. If
           you want to stop playing, observing, or examining an ICS game,
           use an appropriate command from the Action menu, not `New Game'.
           See Action Menu.

      New Shuffle Game
           Similar to `New Game', but allows you to specify a particular
           initial position (according to a standardized numbering system)
           in chess variants which use randomized opening positions (e.g.
           Chess960).  You can also press the `Pick Fixed' button to let
           XBoard generate a random number for you.  The thus selected
           opening position will then persistently be chosen on any
           following New Game command until you use this menu to select
           another. Selecting position number -1 (or pushing the `Randomize'
           button) will produce a newly randomized position on any new game.
           Using this menu item in variants that normally do not shuffle
           their opening position does cause these variants to become
           shuffle variants until you use the `New Shuffle Game' menu to
           explicitly switch the randomization off, or select a new variant.

      New Variant
           Allows you to select a new chess variant in non-ICS mode. (In ICS



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           play, the ICS is responsible for deciding which variant will be
           played, and XBoard adapts automatically.)  The shifted `Alt+V'
           key is a keyboard equivalent. If you play with an engine, the
           engine must be able to play the selected variant, or the command
           will be ignored.  XBoard supports all major variants, such as
           xiangqi, shogi, chess, chess960, Capablanca Chess, shatranj,
           crazyhouse, bughouse.  But not every board size has built-in
           bitmaps for un-orthodox pieces!  Only sizes bulky (72) and
           middling (49) have all pieces, while size petite (33) has most.
           These sizes would have to be set at startup through the `size'
           command-line option when you start up XBoard for such variants to
           be playable.

           You can overrule the default board format of the selected
           variant, (e.g. to play suicide chess on a 6 x 6 board), in this
           dialog, but normally you would not do that, and leave them at '-
           1', which means 'default'.

      Load Game
           Plays a game from a record file. The `Ctrl-O' key is a keyboard
           equivalent.  A pop-up dialog prompts you for the file name. If
           the file contains more than one game, a second pop-up dialog
           displays a list of games (with information drawn from their PGN
           tags, if any), and you can select the one you want.
           Alternatively, you can load the Nth game in the file directly, by
           typing the number `N' after the file name, separated by a space.

           The game file parser will accept PGN (portable game notation), or
           in fact almost any file that contains moves in algebraic
           notation. Notation of the form `P@f7' is accepted for piece-drops
           in bughouse games; this is a nonstandard extension to PGN.  If
           the file includes a PGN position (FEN tag), or an old-style
           XBoard position diagram bracketed by `[--' and `--]' before the
           first move, the game starts from that position. Text enclosed in
           parentheses, square brackets, or curly braces is assumed to be
           commentary and is displayed in a pop-up window. Any other text in
           the file is ignored. PGN variations (enclosed in parentheses)
           also are treated as comments; however, if you rights-click them
           in the comment window, XBoard will shelve the current line, and
           load the the selected variation, so you can step through it.  You
           can later revert to the previous line with the `Revert' command.
           This way you can walk quite complex varation trees with XBoard.
           The nonstandard PGN tag [Variant "varname"] functions similarly
           to the -variant command-line option (see below), allowing games
           in certain chess variants to be loaded. Note that it must appear
           before any FEN tag for XBoard to recognize variant FENs
           appropriately.  There is also a heuristic to recognize chess
           variants from the Event tag, by looking for the strings that the
           Internet Chess Servers put there when saving variant ("wild")
           games.




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      Load Position
           Sets up a position from a position file.  A pop-up dialog prompts
           you for the file name.  The shifted `Ctrl-O' key is a keyboard
           equivalent. If the file contains more than one saved position,
           and you want to load the Nth one, type the number N after the
           file name, separated by a space. Position files must be in FEN
           (Forsythe-Edwards notation), or in the format that the Save
           Position command writes when oldSaveStyle is turned on.

      Load Next Position
           Loads the next position from the last position file you loaded.
           The shifted `PgDn' key is a keyboard equivalent.

      Load Previous Position
           Loads the previous position from the last position file you
           loaded. The shifted `PgUp' key is a keyboard equivalent.  Not
           available if the last position was loaded from a pipe.

      Save Game
           Appends a record of the current game to a file.  The `Ctrl-S' key
           is a keyboard equivalent.  A pop-up dialog prompts you for the
           file name. If the game did not begin with the standard starting
           position, the game file includes the starting position used.
           Games are saved in the PGN (portable game notation) format,
           unless the oldSaveStyle option is true, in which case they are
           saved in an older format that is specific to XBoard. Both formats
           are human-readable, and both can be read back by the `Load Game'
           command.  Notation of the form `P@f7' is accepted for piece-drops
           in bughouse games; this is a nonstandard extension to PGN.

      Save Position
           Appends a diagram of the current position to a file.  The shifted
           `Ctrl+S' key is a keyboard equivalent. A pop-up dialog prompts
           you for the file name. Positions are saved in FEN (Forsythe-
           Edwards notation) format unless the `oldSaveStyle' option is
           true, in which case they are saved in an older, human-readable
           format that is specific to XBoard. Both formats can be read back
           by the `Load Position' command.

      Save Games as Book
           Creates an opening book from the currently loaded game file.  The
           book will be saved on the file specified in the `Common Engine'
           options dialog.  The value of `Book Depth' specified in that same
           dialog will be used to determine how many moves of each game will
           be added to the internal book buffer.  This command can take a
           long time to process, and the size of the buffer is currently
           limited.  At the end the buffer will be saved as a Polyglot book,
           but the buffer will ot be cleared, so that you can continue
           adding games from other game files.





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      Mail Move
      Reload CMail Message
           See CMail.

      Exit Exits from XBoard. The `Ctrl-Q' key is a keyboard equivalent.

    Edit Menu
      Copy Game
           Copies a record of the current game to an internal clipboard in
           PGN format and sets the X selection to the game text. The `Ctrl-
           C' key is a keyboard equivalent. The game can be pasted to
           another application (such as a text editor or another copy of
           XBoard) using that application's paste command.  In many X
           applications, such as xterm and emacs, the middle mouse button
           can be used for pasting; in XBoard, you must use the Paste Game
           command.

      Copy Position
           Copies the current position to an internal clipboard in FEN
           format and sets the X selection to the position text. The shifted
           `Ctrl-C' key is a keyboard equivalent.  The position can be
           pasted to another application (such as a text editor or another
           copy of XBoard) using that application's paste command.  In many
           X applications, such as xterm and emacs, the middle mouse button
           can be used for pasting; in XBoard, you must use the Paste
           Position command.

      Copy Game List
           Copies the current game list to the clipboard, and sets the X
           selection to this text.  A format of comma-separated double-
           quoted strings is used, including all tags, so it can be easily
           imported into spread-sheet programs.

      Paste Game
           Interprets the current X selection as a game record and loads it,
           as with Load Game. The `Ctrl-V' key is a keyboard equivalent.

      Paste Position
           Interprets the current X selection as a FEN position and loads
           it, as with Load Position. The shifted `Ctrl-V' key is a keyboard
           equivalent.

      Edit Game
           Allows you to make moves for both Black and White, and to change
           moves after backing up with the `Backward' command. The clocks do
           not run. The `Ctrl-E' key is a keyboard equivalent.

           In chess engine mode, the chess engine continues to check moves
           for legality but does not participate in the game. You can bring
           the chess engine into the game by selecting `Machine White',
           `Machine Black', or `Two Machines'.



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           In ICS mode, the moves are not sent to the ICS: `Edit Game' takes
           XBoard out of ICS Client mode and lets you edit games locally.
           If you want to edit games on ICS in a way that other ICS users
           can see, use the ICS `examine' command or start an ICS match
           against yourself.

      Edit Position
           Lets you set up an arbitrary board position.  The shifted `Ctrl-
           E' key is a keyboard equivalent.  Use mouse button 1 to drag
           pieces to new squares, or to delete a piece by dragging it off
           the board or dragging an empty square on top of it.  To drop a
           new piece on a square, press mouse button 2 or 3 over the square.
           This puts a white or black pawn in the square, respectively, but
           you can change that to any other piece type by dragging the mouse
           down before you release the button.  You will then see the piece
           on the originally clicked square cycle through the available
           pieces (including those of opposite color), and can release the
           button when you see the piece you want.  To alter the side to
           move, you can click the clock (the words White and Black above
           the board) of the side you want to give the move to.  To clear
           the board you can click the clock of the side that alread has the
           move (which is highlighted in black).  The old behavior with a
           piece menu can still be configured with the aid of the
           `pieceMenu' option.  Selecting `Edit Position' causes XBoard to
           discard all remembered moves in the current game.

           In ICS mode, changes made to the position by `Edit Position' are
           not sent to the ICS: `Edit Position' takes XBoard out of `ICS
           Client' mode and lets you edit positions locally. If you want to
           edit positions on ICS in a way that other ICS users can see, use
           the ICS `examine' command, or start an ICS match against
           yourself.  (See also the ICS Client topic above.)

      Edit Tags
           Lets you edit the PGN (portable game notation) tags for the
           current game. After editing, the tags must still conform to the
           PGN tag syntax:

               <tag-section> ::= <tag-pair> <tag-section>
                                       <empty>
               <tag-pair> ::= [ <tag-name> <tag-value> ]
               <tag-name> ::= <identifier>
               <tag-value> ::= <string>

           See the PGN Standard for full details. Here is an example:

               [Event "Portoroz Interzonal"]
               [Site "Portoroz, Yugoslavia"]
               [Date "1958.08.16"]
               [Round "8"]
               [White "Robert J. Fischer"]



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               [Black "Bent Larsen"]
               [Result "1-0"]

           Any characters that do not match this syntax are silently
           ignored. Note that the PGN standard requires all games to have at
           least the seven tags shown above. Any that you omit will be
           filled in by XBoard with `?' (unknown value), or `-'
           (inapplicable value).

      Edit Comment
           Adds or modifies a comment on the current position. Comments are
           saved by `Save Game' and are displayed by `Load Game', PGN
           variations will also be printed in this window, and can be
           promoted to main line by right-clicking them.  `Forward', and
           `Backward'.

      Edit Book
           Pops up a window listing the moves available in the GUI book
           (specified in the `Common Engine Settings' dialog) from the
           currently displayed position, together with their weights and
           (optionally in braces) learn info. You can then edit this list,
           and the new list will be stored back into the book when you press
           OK.  Note that the listed percentages are neither used, nor
           updated when you change the weights; they are just there as an
           optical aid.

      Revert
      Annotate
           If you are examining an ICS game and Pause mode is off, Revert
           issues the ICS command `revert'.  In local mode, when you were
           editing or analyzing a game, and the `-variations' command-line
           option is switched on, you can start a new variation by holding
           the Shift key down while entering a move not at the end of the
           game.  Variations can also become the currently displayed line by
           clicking a PGN variation displayed in the Comment window.  This
           can be applied recursively, so that you can analyze variations on
           variations; each time you create a new variation by entering an
           alternative move with Shift pressed, or select a new one from the
           Comment window, the current variation will be shelved. `Revert'
           allows you to return to the most recently shelved variation.  The
           difference between `Revert' and `Annotate' is that with the
           latter, the variation you are now abandoning will be added as a
           comment (in PGN variation syntax, i.e. between parentheses) to
           the original move where you deviated, for later recalling.  The
           `Home' key is a keyboard equivalent to `Revert'.

      Truncate Game
           Discards all remembered moves of the game beyond the current
           position. Puts XBoard into `Edit Game' mode if it was not there
           already.  The `End' key is a keyboard equivalent.




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      Backward
           Steps backward through a series of remembered moves.  The `[<]'
           button and the `Alt+LeftArrow' key are equivalents, as is turning
           the mouse wheel towards you.  In addition, pressing the Control
           key steps back one move, and releasing it steps forward again.

           In most modes, `Backward' only lets you look back at old
           positions; it does not retract moves. This is the case if you are
           playing against a chess engine, playing or observing a game on an
           ICS, or loading a game.  If you select `Backward' in any of these
           situations, you will not be allowed to make a different move. Use
           `Retract Move' or `Edit Game' if you want to change past moves.

           If you are examining an ICS game, the behavior of `Backward'
           depends on whether XBoard is in Pause mode. If Pause mode is off,
           `Backward' issues the ICS backward command, which backs up
           everyone's view of the game and allows you to make a different
           move. If Pause mode is on, `Backward' only backs up your local
           view.

      Forward
           Steps forward through a series of remembered moves (undoing the
           effect of `Backward') or forward through a game file. The `[>]'
           button and the `Alt+RightArrow' key are equivalents, as is
           turning the mouse wheel away from you.

           If you are examining an ICS game, the behavior of Forward depends
           on whether XBoard is in Pause mode. If Pause mode is off,
           `Forward' issues the ICS forward command, which moves everyone's
           view of the game forward along the current line. If Pause mode is
           on, `Forward' only moves your local view forward, and it will not
           go past the position that the game was in when you paused.

      Back to Start
           Jumps backward to the first remembered position in the game.  The
           `[<<]' button and the `Alt+Home' key are equivalents.

           In most modes, Back to Start only lets you look back at old
           positions; it does not retract moves. This is the case if you are
           playing against a local chess engine, playing or observing a game
           on a chess server, or loading a game. If you select `Back to
           Start' in any of these situations, you will not be allowed to
           make different moves. Use `Retract Move' or `Edit Game' if you
           want to change past moves; or use Reset to start a new game.

           If you are examining an ICS game, the behavior of @samp{Back to
           Start} depends on whether XBoard is in Pause mode. If Pause mode
           is off, `Back to Start' issues the ICS `backward 999999' command,
           which backs up everyone's view of the game to the start and
           allows you to make different moves. If Pause mode is on,
           @samp{Back to Start} only backs up your local view.



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      Forward to End
           Jumps forward to the last remembered position in the game. The
           `[>>]' button and the `Alt+End' key are equivalents.

           If you are examining an ICS game, the behavior of @samp{Forward
           to End} depends on whether XBoard is in Pause mode. If Pause mode
           is off, `Forward to End' issues the ICS `forward 999999' command,
           which moves everyone's view of the game forward to the end of the
           current line. If Pause mode is on, `Forward to End' only moves
           your local view forward, and it will not go past the position
           that the game was in when you paused.

    View Menu
      Flip View
           Inverts your view of the chess board for the duration of the
           current game. Starting a new game returns the board to normal.
           The `F2' key is a keyboard equivalent.

      Show Engine Output
           Shows or hides a window in which the thinking output of any
           loaded engines is displayed. The shifted `Alt+O' key is a
           keyboard equivalent.  XBoard will display lines of thinking
           output of the same depth ordered by score, (highest score on
           top), rather than in the order the engine produced them. Usually
           this amounts to the same, as a normal engine search will only
           find new PV (and emit it as thinking output) when it searches a
           move with a higher score than the previous variation. But when
           the engine is in multi-variation mode this needs not always be
           true, and it is more convenient for someone analyzing games to
           see the moves sorted by score. The order in which the engine
           found them is only of interest to the engine author, and can
           still be deduced from the time or node count printed with the
           line.  Right-clicking a line in this window, and then moving the
           mouse vertically with the right button kept down, will make
           XBoard play through the PV listed there.  The use of the board
           window as 'variation board' will normally end when you release
           the right button, or when the opponent plays a move.  But beware:
           in Analysis mode, moves thus played out will be added to the
           game.  The Engine-Output pane for each engine will contain a
           header displaying the multi-PV status and a list of excluded
           moves in Analysis mode, which are also responsive to right-
           clicking.

      Show Move History
           Shows or hides a list of moves of the current game.  The shifted
           `Alt+H' key is a keyboard equivalent.  This list allows you to
           move the display to any earlier position in the game by clicking
           on the corresponding move.

      Show Evaluation Graph
           Shows or hides a window which displays a graph of how the engine



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           score(s) evolved as a function of the move number. The shifted
           `Alt+E' key is a keyboard equivalent.  Clicking on the graph will
           bring the corresponding position in the board display.

      Show Game List
           Shows or hides the list of games generated by the last `Load
           Game' command. The shifted `Alt+G' key is a keyboard equivalent.

      Tags Pops up a window which shows the PGN (portable game notation)
           tags for the current game. For now this is a duplicate of the
           `Edit Tags' item in the `Edit' menu.

      Comments
           Pops up a window which shows any comments to or variations on the
           current move.  For now this is a duplicate of the `Edit Comment'
           item in the `Edit' menu.

      ICS Input Box
           If this option is set in ICS mode, XBoard creates an extra window
           that you can use for typing in ICS commands.  The input box is
           especially useful if you want to type in something long or do
           some editing on your input, because output from ICS doesn't get
           mixed in with your typing as it would in the main terminal
           window.

      Open Chat Window
           This menu item opens a window in which you can conduct upto 5
           chats with other ICS users (or channels).  To use the window,
           write the name of your chat partner, the channel number, or the
           words 'shouts', 'whispers', 'cshouts' in the upper field (closing
           with <Enter>).  Everything you type in the lowest field will then
           automatically be sent to the mentioned party, while everything
           that party sends to you will appear in the central text box,
           rather than appear in the ICS console.  The row of buttons allow
           you to choose between chat; to start a new chat, just select an
           empty button, and complete the `Chat partner' field.

      Board
           Summons a dialog where you can customize the look of the chess
           board.  Here you can specify the directory from which piece
           images should be taken, when you don't want to use the built-in
           piece images (see `pieceImageDirectory' option), external images
           to be used for the board squares (`liteBackTextureFile' and
           `darkBackTextureFile' options), and square and piece colors for
           the default pieces.

      Game List Tags
           a duplicate of the Game List dialog in the Options menu.

    Mode Menu




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      Machine White
           Tells the chess engine to play White. The `Ctrl-W' key is a
           keyboard equivalent.

      Machine Black
           Tells the chess engine to play Black.  The `Ctrl-B' key is a
           keyboard equivalent.

      Two Machines
           Plays a game between two chess engines.  The `Ctrl-T' key is a
           keyboard equivalent.

      Analysis Mode
           XBoard tells the chess engine to start analyzing the current
           game/position and shows you the analysis as you move pieces
           around.  The `Ctrl-A' key is a keyboard equivalent.  Note: Some
           chess engines do not support Analysis mode.

           To set up a position to analyze, you do the following:

           1. Select Edit Position from the Mode Menu

           2. Set up the position.  Use the middle and right buttons to
           bring up the white and black piece menus.

           3. When you are finished, click on either the Black or White
           clock to tell XBoard which side moves first.

           4. Select Analysis Mode from the Mode Menu to start the analysis.

           You can now play legal moves to create follow-up positions for
           the engine to analyze, while the moves will be remembered as a
           stored game, and then step backward through this game to take the
           moves back.  Note that you can also click on the clocks to set
           the opposite side to move (adding a so-called `null move' to the
           game).

           You can also tell the engine to exclude some moves from analysis.
           (Engines that do not support the exclude-moves feature will
           ignore this, however.) The general way to do this is to play the
           move you want to exclude starting with a double click on the
           piece.  When you use drag-drop moving, the piece you grab with a
           double click will also remain on its square, to show you that you
           are not really making the move, but just forbid it from the
           current position.  Playing a thus excluded move a second time
           will include it again.  Excluded moves will be listed as text in
           a header line in the Engine Output window, and you can also re-
           include them by right-clicking them there.  This header line will
           also contain the words 'best' and 'tail'; right-clicking those
           will exclude the currently best move, or all moves not explicitly
           listed in the header line.  Once you leave the current position



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           all memory of excluded moves will be lost when you return there.

           Selecting this menu item while already in `Analysis Mode' will
           toggle the participation of the second engine in the analysis.
           The output of this engine will then be shown in the lower pane of
           the Engine Output window.  The analysis function can also be used
           when observing games on an ICS with an engine loaded (zippy
           mode); the engine then will analyse the positions as they occur
           in the observed game.


      Analyze Game
           This option subjects the currently loaded game to automatic
           analysis by the loaded engine.  The `Ctrl-G' key is a keyboard
           equivalent.  XBoard will start auto-playing the game from the
           currently displayed position, while the engine is analyzing the
           current position.  The game will be annotated with the results of
           these analyses.  In particlar, the score and depth will be added
           as a comment, and the PV will be added as a variation.

           Normally the analysis would stop after reaching the end of the
           game.  But when a game is loaded from a multi-game file while
           `Analyze Game' was already switched on, the analysis will
           continue with the next game in the file until the end of the file
           is reached (or you switch to another mode).

           The time the engine spends on analyzing each move can be
           controlled through the command-line option `-timeDelay', which
           can also be set from the `Load Game Options' menu dialog.  Note:
           Some chess engines do not support Analysis mode.

      Edit Game
           Duplicate of the item in the Edit menu.  Note that `Edit Game' is
           the idle mode of XBoard, and can be used to get you out of other
           modes. E.g. to stop analyzing, stop a game between two engines or
           stop editing a position.

      Edit Position
           Duplicate of the item in the Edit menu.

      Training
           Training mode lets you interactively guess the moves of a game
           for one of the players. You guess the next move of the game by
           playing the move on the board. If the move played matches the
           next move of the game, the move is accepted and the opponent's
           response is auto-played.  If the move played is incorrect, an
           error message is displayed.  You can select this mode only while
           loading a game (that is, after selecting `Load Game' from the
           File menu).  While XBoard is in `Training' mode, the navigation
           buttons are disabled.




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                                   $Date:



      ICS Client
           This is the normal mode when XBoard is connected to a chess
           server.  If you have moved into Edit Game or Edit Position mode,
           you can select this option to get out.

           To use xboard in ICS mode, run it in the foreground with the -ics
           option, and use the terminal you started it from to type commands
           and receive text responses from the chess server.  See Chess
           Servers below for more information.

           XBoard activates some special position/game editing features when
           you use the `examine' or `bsetup' commands on ICS and you have
           `ICS Client' selected on the Mode menu.  First, you can issue the
           ICS position-editing commands with the mouse.  Move pieces by
           dragging with mouse button 1.  To drop a new piece on a square,
           press mouse button 2 or 3 over the square.  This brings up a menu
           of white pieces (button 2) or black pieces (button 3).
           Additional menu choices let you empty the square or clear the
           board.  Click on the White or Black clock to set the side to
           play.  You cannot set the side to play or drag pieces to
           arbitrary squares while examining on ICC, but you can do so in
           `bsetup' mode on FICS.  In addition, the menu commands `Forward',
           `Backward', `Pause', and `Stop Examining' have special functions
           in this mode; see below.

      Machine Match
           Starts a match between two chess programs, with a number of games
           and other parameters set through the `Match Options' menu dialog.
           When a match is already running, selecting this item will make
           XBoard drop out of match mode after the current game finishes.

      Pause
           Pauses updates to the board, and if you are playing against a
           chess engine, also pauses your clock. To continue, select `Pause'
           again, and the display will automatically update to the latest
           position.  The `P' button and keyboard `Pause' key are
           equivalents.

           If you select Pause when you are playing against a chess engine
           and it is not your move, the chess engine's clock will continue
           to run and it will eventually make a move, at which point both
           clocks will stop. Since board updates are paused, however, you
           will not see the move until you exit from Pause mode (or select
           Forward).  This behavior is meant to simulate adjournment with a
           sealed move.

           If you select Pause while you are observing or examining a game
           on a chess server, you can step backward and forward in the
           current history of the examined game without affecting the other
           observers and examiners, and without having your display jump
           forward to the latest position each time a move is made. Select



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           Pause again to reconnect yourself to the current state of the
           game on ICS.

           If you select `Pause' while you are loading a game, the game
           stops loading. You can load more moves manually by selecting
           `Forward', or resume automatic loading by selecting `Pause'
           again.

    Action Menu
      Accept
           Accepts a pending match offer. The `F3' key is a keyboard
           equivalent.  If there is more than one offer pending, you will
           have to type in a more specific command instead of using this
           menu choice.

      Decline
           Declines a pending offer (match, draw, adjourn, etc.).  The `F4'
           key is a keyboard equivalent. If there is more than one offer
           pending, you will have to type in a more specific command instead
           of using this menu choice.

      Call Flag
           Calls your opponent's flag, claiming a win on time, or claiming a
           draw if you are both out of time. The `F5' key is a keyboard
           equivalent.  You can also call your opponent's flag by clicking
           on his clock.

      Draw Offers a draw to your opponent, accepts a pending draw offer from
           your opponent, or claims a draw by repetition or the 50-move
           rule, as appropriate. The `F6' key is a keyboard equivalent.

      Adjourn
           Asks your opponent to agree to adjourning the current game, or
           agrees to a pending adjournment offer from your opponent.  The
           `F7' key is a keyboard equivalent.

      Abort
           Asks your opponent to agree to aborting the current game, or
           agrees to a pending abort offer from your opponent.  The `F8' key
           is a keyboard equivalent. An aborted game ends immediately
           without affecting either player's rating.

      Resign
           Resigns the game to your opponent. The `F9' key is a keyboard
           equivalent.

      Stop Observing
           Ends your participation in observing a game, by issuing the ICS
           observe command with no arguments. ICS mode only.  The `F10' key
           is a keyboard equivalent.




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      Stop Examining
           Ends your participation in examining a game, by issuing the ICS
           unexamine command. ICS mode only.  The `F11' key is a keyboard
           equivalent.

      Upload to Examine
           Create an examined game of the proper variant on the ICS, and
           send the game there that is currenty loaded in XBoard (e.g.
           through pasting or loading from file).  You must be connected to
           an ICS for this to work.

      Adjudicate to White
      Adjudicate to Black
      Adjudicate Draw
           Terminate an ongoing game in Two-Machines mode (including match
           mode), with as result a win for white, for black, or a draw,
           respectively.  The PGN file of the game will accompany the result
           string by the comment "user adjudication".

    Engine Menu
      Load Engine
           Pops up a dialog where you can select or specify an engine to be
           loaded.  You will always have to indicate whether you want to
           load the engine as first or second engine, through the Load
           menitioned engine as drop-down list at the bottom of the
           dialog. You can even replace engines during a game, without
           disturbing that game.  (Beware that after loading an engine,
           XBoard will always be in Edit Game mode, so you will have to tell
           the new engine what to do before it does anything!) When you
           select an already installed engine from the Select Engine from
           List drop-down list, all other fields of the dialog will be
           ignored. In other cases, you have to specify the engine
           executable, possible arguments on the engine command line (if the
           engine docs say the engine needs any), and the directory where
           the engine should look for its files (if this cannot be deduced
           automatically from the specification of the engine executable).
           You will also have to specify (with the aid of checkboxes) if the
           engine is UCI. If Add this engine to the list is ticked
           (which it is by default), the engine will be added to the list of
           installed engines in your settings file, (provided you save the
           settings!), so that next time you can select it from the drop-
           down list. You can also specify a nickname, under which the
           engine will then appear in that drop-down list, and even choose
           to use that nickname for it in PGN files for engine-engine games.
           The info you supply with the checkboxes whether the engine should
           use GUI book, or (for variant engines) automatically switch to
           the current variant when loaded, will also be included in the
           list. For obsolete XBoard engines, which would normally take a
           long delay to load because XBoard is waiting for a response they
           will not give, you can tick WB protocol v1 to speed up the
           loading process.



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                                   $Date:



      Engine #N Settings
           Pop up a menu dialog to alter the settings specific to the
           applicable engine.  (The second engine is only accessible once it
           has been used in Two-Machines mode.) For each parameter the
           engine allows to be set, a control element will appear in this
           dialog that can be used to alter the value.  Depending on the
           type of parameter (text string, number, multiple choice, on/off
           switch, instantaneous signal) the appropriate control will
           appear, with a description next to it.  XBoard has no idea what
           these values mean; it just passes them on to the engine.  How
           this dialog looks is completely determined by the engine, and
           XBoard just passes it on to the user.  Many engines do not have
           any parameters that can be set by the user, and in that case the
           dialog will be empty (except for the OK and cancel buttons).  UCI
           engines usually have many parameters. (But these are only visible
           with a sufficiently modern version of the Polyglot adapter needed
           to run UCI engines, e.g. Polyglot 1.4.55b.) For native XBoard
           engines this is less common.

      Hint Displays a move hint from the chess engine.

      Book Displays a list of possible moves from the chess engine's opening
           book.  The exact format depends on what chess engine you are
           using.  With GNU Chess 4, the first column gives moves, the
           second column gives one possible response for each move, and the
           third column shows the number of lines in the book that include
           the move from the first column. If you select this option and
           nothing happens, the chess engine is out of its book or does not
           support this feature.

      Move Now
           Forces the chess engine to move immediately. Chess engine mode
           only.  The `Ctrl-M' key is a keyboard equivalent.

      Retract Move
           Retracts your last move. In chess engine mode, you can do this
           only after the chess engine has replied to your move; if the
           chess engine is still thinking, use `Move Now' first. In ICS
           mode, `Retract Move' issues the command `takeback 1' or `takeback
           2' depending on whether it is your opponent's move or yours.  The
           `Ctrl-X' key is a keyboard equivalent.

      Recently Used Engines
           At the bottom of the engine menu there can be a list of names of
           engines that you recently loaded through the Load Engine menu
           dialog in previous sessions.  Clicking on such a name will load
           that engine as first engine, so you won't have to search for it
           in your list of installed engines, if that is very long.  The
           maximum number of displayed engine names is set by the
           `recentEngines'command-line option.




                                   - 17 -      Formatted:  December 21, 2024






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                                   $Date:



    Options Menu
      The following items to set option values appear in the dialog summoned
      by the general Options menu item.

      Absolute Analysis Scores
           Controls if scores on the Engine Output window during analysis
           will be printed from the white or the side-to-move point-of-view.

      Almost Always Queen
           If this option is on, 7th-rank pawns automatically change into
           Queens when you pick them up, and when you drag them to the
           promotion square and release them there, they will promote to
           that.  But when you drag such a pawn backwards first, its
           identity will start to cycle through the other available pieces.
           This will continue until you start to move it forward; at which
           point the identity of the piece will be fixed, so that you can
           safely put it down on the promotion square.  If this option is
           off, what happens depends on the option `alwaysPromoteToQueen',
           which would force promotion to Queen when true.  Otherwise XBoard
           would bring up a dialog box whenever you move a pawn to the last
           rank, asking what piece you want to promote to.

      Animate Dragging
           If Animate Dragging is on, while you are dragging a piece with
           the mouse, an image of the piece follows the mouse cursor.  If
           Animate Dragging is off, there is no visual feedback while you
           are dragging a piece, but if Animate Moving is on, the move will
           be animated when it is complete.

      Animate Moving
           If Animate Moving is on, all piece moves are animated.  An image
           of the piece is shown moving from the old square to the new
           square when the move is completed (unless the move was already
           animated by Animate Dragging).  If Animate Moving is off, a moved
           piece instantly disappears from its old square and reappears on
           its new square when the move is complete.  The shifted `Ctrl-A'
           key is a keyboard equivalent.

      Auto Flag
           If this option is on and one player runs out of time before the
           other, XBoard will automatically call his flag, claiming a win on
           time.  The shifted `Ctrl-F' key is a keyboard equivalent.  In ICS
           mode, Auto Flag will only call your opponent's flag, not yours,
           and the ICS may award you a draw instead of a win if you have
           insufficient mating material.  In local chess engine mode, XBoard
           may call either player's flag and will not take material into
           account (?).

      Auto Flip View
           If the Auto Flip View option is on when you start a game, the
           board will be automatically oriented so that your pawns move from



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                                   $Date:



           the bottom of the window towards the top.

           If you are playing a game on an ICS, the board is always oriented
           at the start of the game so that your pawns move from the bottom
           of the window towards the top. Otherwise, the starting
           orientation is determined by the `flipView' command line option;
           if it is false (the default), White's pawns move from bottom to
           top at the start of each game; if it is true, Black's pawns move
           from bottom to top. See User interface options.

      Blindfold
           If this option is on, XBoard displays the board as usual but does
           not display pieces or move highlights.  You can still move in the
           usual way (with the mouse or by typing moves in ICS mode), even
           though the pieces are invisible.

      Drop Menu
           Controls if right-clicking the board in crazyhouse / bughouse
           will pop up a menu to drop a piece on the clicked square (old,
           deprecated behavior) or allow you to step through an engine PV
           (new, recommended behavior).

      Enable Variation Trees
           If this option is on, playing a move in Edit Game or Analyze mode
           while keeping the Shift key pressed will start a new variation.
           You can then recall the previous line through the `Revert' menu
           item.  When off, playing a move will truncate the game and append
           the move irreversibly.

      Hide Thinking
           If this option is off, the chess engine's notion of the score and
           best line of play from the current position is displayed as it is
           thinking. The score indicates how many pawns ahead (or if
           negative, behind) the chess engine thinks it is. In matches
           between two machines, the score is prefixed by `W' or `B' to
           indicate whether it is showing White's thinking or Black's, and
           only the thinking of the engine that is on move is shown.  The
           shifted `Ctrl-H' key is a keyboard equivalent.

      Highlight Last Move
           If Highlight Last Move is on, after a move is made, the starting
           and ending squares remain highlighted. In addition, after you use
           Backward or Back to Start, the starting and ending squares of the
           last move to be unmade are highlighted.

      Highlight with Arrow
           Causes the highlighting described in Highlight Last Move to be
           done by drawing an arrow between the highlighted squares, so that
           it is visible even when the width of the grid lines is set to
           zero.




                                   - 19 -      Formatted:  December 21, 2024






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                                   $Date:



      Move Sound
           Enables the sounding of an audible signal when the computer
           performs a move.  For the selection of the sound, see `Sound
           Options'.  If you turn on this option when using XBoard with the
           Internet Chess Server, you will probably want to give the `set
           bell 0' command to the ICS, since otherwise the ICS will ring the
           terminal bell after every move (not just yours). (The `.icsrc'
           file is a good place for this; see ICS options.)

      One-Click Moving
           If this option is on, XBoard does not wait for you to click both
           the from- and the to-square, or drag the piece, but performs a
           move as soon as it is uniqely specified.  This applies to
           clicking an own piece that only has a single legal move, clicking
           an empty square or opponent piece where only one of your pieces
           can move (or capture) to.  Furthermore, a double-click on a piece
           that can only make a single capture will cause that capture to be
           made.  Promoting a Pawn by clicking its to-square will suppress
           the promotion popup or other methods for selecting an under-
           promotion, and make it promote to Queen.

      Periodic Updates
           If this option is off (or if you are using a chess engine that
           does not support periodic updates), the analysis window will only
           be updated when the analysis changes. If this option is on, the
           Analysis Window will be updated every two seconds.

      Play Move(s) of Clicked PV
           If this option is on, right-clicking a PV in the Engine Output
           window during Analyze mode will cause the first move of that PV
           to be played.  You could also play more than one (or no) PV move
           by moving the mouse to engage in the PV walk such a right-click
           will start, to seek out another position along the PV where you
           want to continue the analysis, before releasing the mouse button.

      Ponder Next Move
           If this option is off, the chess engine will think only when it
           is on move.  If the option is on, the engine will also think
           while waiting for you to make your move.  The shifted `Ctrl-P'
           key is a keyboard equivalent.

      Popup Exit Message
           If this option is on, when XBoard wants to display a message just
           before exiting, it brings up a modal dialog box and waits for you
           to click OK before exiting.  If the option is off, XBoard prints
           the message to standard error (the terminal) and exits
           immediately.

      Popup Move Errors
           If this option is off, when you make an error in moving (such as
           attempting an illegal move or moving the wrong color piece), the



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                                   $Date:



           error message is displayed in the message area.  If the option is
           on, move errors are displayed in small pop-up windows like other
           errors.  You can dismiss an error pop-up either by clicking its
           OK button or by clicking anywhere on the board, including down-
           clicking to start a move.

      Scores in Move List
           If this option is on, XBoard will display the depth and score of
           engine moves in the Move List, in the format of a PGN comment.

      Show Coords
           If this option is on, XBoard displays algebraic coordinates along
           the board's left and bottom edges.

      Show Target Squares
           If this option is on, all squares a piece that is 'picked up'
           with the mouse can legally move to are highighted with a fat
           colored dot in the highlightColor (non-captures) or
           premoveHighlightColor (captures).  Legality testing must be on
           for XBoard to know how the piece moves.

      Test Legality
           If this option is on, XBoard tests whether the moves you try to
           make with the mouse are legal and refuses to let you make an
           illegal move.  The shifted `Ctrl-L' key is a keyboard equivalent.
           Moves loaded from a file with `Load Game' are also checked.  If
           the option is off, all moves are accepted, but if a local chess
           engine or the ICS is active, they will still reject illegal
           moves.  Turning off this option is useful if you are playing a
           chess variant with rules that XBoard does not understand.
           (Bughouse, suicide, and wild variants where the king may castle
           after starting on the d file are generally supported with Test
           Legality on.)

      Flash Moves
      Flash Rate
           If this option is non-zero, whenever a move is completed, the
           moved piece flashes the specified number of times.  The flash-
           rate setting determines how rapidly this flashing occurs.

      Animation Speed
           Determines the duration (in msec) of an animation step, when
           `Animate Moving' is swiched on.

      Zoom factor in Evaluation Graph
           Sets the valueof the `evalZoom' option, indicating the factor by
           which the score interval (-1,1) should be blown up on the
           vertical axis of the Evaluation Graph.

      Pops up a sub-menu where you can set the time-control parameters
      interactively.  Allows you to select classical or incremental time



                                   - 21 -      Formatted:  December 21, 2024






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                                   $Date:



      controls, set the moves per session, session duration, and time
      increment.  Also allows specification of time-odds factors for one or
      both engines.  If an engine is given a time-odds factor N, all time
      quota it gets, be it at the beginning of a session or through the time
      increment or fixed time per move, will be divided by N.  The shifted
      `Alt+T' key is a keyboard equivalent.

      Pops up a sub-menu where you can set some engine parameters common to
      most engines, such as hash-table size, tablebase cache size, maximum
      number of processors that SMP engines can use, and where to find the
      Polyglot adapter needed to run UCI engines under XBoard. The feature
      that allows setting of these parameters on engines is new since XBoard
      4.3.15, so not many XBoard/WinBoard engines respond to it yet, but UCI
      engines should.

      It is also possible to specify a GUI opening book here, i.e. an
      opening book that XBoard consults for any position a playing engine
      gets in.  It then forces the engine to play the book move, rather than
      to think up its own, if that position is found in the book.  The book
      can switched on and off independently for either engine.  The way book
      moves are chosen can be influenced through the settings of book depth
      and variety.  After both sides have played more moves than the
      specified depth, the book will no longer be consulted.  When the
      variety is set to 50, moves will be played with the probability
      specified in the book.  When set to 0, only the move(s) with the
      highest probability will be played.  When set to 100, all listed moves
      will be played with equal pobability.  Other settings interpolate
      between that.  The shifted `Alt+U' key is a keyboard equivalent.

      Pops up a sub-menu where you can enable or disable various
      adjudications that XBoard can perform in engine-engine games.  The
      shifted `Alt+J' key is a keyboard equivalent.  You can instruct XBoard
      to detect and terminate the game on checkmate or stalemate, even if
      the engines would not do so, to verify engine result claims
      (forfeiting engines that make false claims), rather than naively
      following the engine, to declare draw on positions which can never be
      won for lack of mating material, (e.g. KBK), or which are impossible
      to win unless the opponent seeks its own demise (e.g. KBKN).  For
      these adjudications to work, `Test Legality' should be switched on.
      It is also possible to instruct XBoard to enforce a 50-move or 3-
      fold-repeat rule and automatically declare draw (after a user-
      adjustable number of moves or repeats) even if the engines are
      prepared to go on.  It is also possible to have XBoard declare draw on
      games that seem to drag on forever, or adjudicate a loss if both
      engines agree (for 3 consecutive moves) that one of them is behind
      more than a user-adjustable score threshold.  For the latter
      adjudication to work, XBoard should be able to properly understand the
      engine's scores. To facilitate the latter, you can inform xboard here
      if the engines report scores from the viewpoint of white, or from that
      of their own color.




                                   - 22 -      Formatted:  December 21, 2024






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                                   $Date:



      The following options occur in a dialog summoned by the ICS Options
      menu item.

      Auto Kibitz
           Setting this option when playing with or aginst a chess program
           on an ICS will cause the last line of thinking output of the
           engine before its move to be sent to the ICS in a kibitz command.
           In addition, any kibitz message received through the ICS from an
           opponent chess program will be diverted to the engine-output
           window, (and suppressed in the console), where you can play
           through its PV by right-clicking it.

      Auto Comment
           If this option is on, any remarks made on ICS while you are
           observing or playing a game are recorded as a comment on the
           current move.  This includes remarks made with the ICS commands
           `say', `tell', `whisper', and `kibitz'.  Limitation: remarks that
           you type yourself are not recognized; XBoard scans only the
           output from ICS, not the input you type to it.

      Auto Observe
           If this option is on and you add a player to your `gnotify' list
           on ICS, XBoard will automatically observe all of that player's
           games, unless you are doing something else (such as observing or
           playing a game of your own) when one starts.  The games are
           displayed from the point of view of the player on your gnotify
           list; that is, his pawns move from the bottom of the window
           towards the top.  Exceptions:  If both players in a game are on
           your gnotify list, if your ICS `highlight' variable is set to 0,
           or if the ICS you are using does not properly support observing
           from Black's point of view, you will see the game from White's
           point of view.

      Auto Raise Board
           If this option is on, whenever a new game begins, the chessboard
           window is deiconized (if necessary) and raised to the top of the
           stack of windows.

      Auto Save
           If this option is true, at the end of every game XBoard prompts
           you for a file name and appends a record of the game to the file
           you specify. Disabled if the `saveGameFile' command-line option
           is set, as in that case all games are saved to the specified
           file.  See Load and Save options.

      Background Observe
           Setting this option will make XBoard suppress display of any
           boards from observed games while you are playing.  In stead the
           last such board will be remembered, and shown to you when you
           right-click the board.  This allows you to peek at your bughouse
           partner's game when you want, without disturbing your own game



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           too much.

      Dual Board
           Setting this option in combination with `Background Observe' will
           display boards of observed games while you are playing on a
           second board next to that of your own game.

      Get Move List
           If this option is on, whenever XBoard receives the first board of
           a new ICS game (or a different game from the one it is currently
           displaying), it retrieves the list of past moves from the ICS.
           You can then review the moves with the `Forward' and `Backward'
           commands or save them with `Save Game'.  You might want to turn
           off this option if you are observing several blitz games at once,
           to keep from wasting time and network bandwidth fetching the move
           lists over and over.  When you turn this option on from the menu,
           XBoard immediately fetches the move list of the current game (if
           any).

      Quiet Play
           If this option is on, XBoard will automatically issue an ICS `set
           shout 0' command whenever you start a game and a `set shout 1'
           command whenever you finish one.  Thus, you will not be
           distracted by shouts from other ICS users while playing.

      Seek Graph
           Setting this option will cause XBoard to display an graph of
           currently active seek ads when you left-click the board while
           idle and logged on to an ICS.

      Auto-Refresh Seek Graph
           In combination with the `Seek Graph' option this will cause
           automatic update of the seek graph while it is up.  This only
           works on FICS and ICC, and requires a lot of bandwidth on a busy
           server.

      Premove
      Premove White
      Premove Black
      First White Move
      First Black Move
           If this option is on while playing a game on an ICS, you can
           register your next planned move before it is your turn.  Move the
           piece with the mouse in the ordinary way, and the starting and
           ending squares will be highlighted with a special color (red by
           default).  When it is your turn, if your registered move is
           legal, XBoard will send it to ICS immediately; if not, it will be
           ignored and you can make a different move.  If you change your
           mind about your premove, either make a different move, or
           double-click on any piece to cancel the move entirely.




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           You can also enter premoves for the first white and black moves
           of the game.

      ICS Alarm
      ICS Alarm Time
           When this option is on, an alarm sound is played when your clock
           counts down to the icsAlarmTime in an ICS game.  (By default, the
           time is 5 seconds, but you can pecify other values with the Alarm
           Time spin control.) For games with time controls that include an
           increment, the alarm will sound each time the clock counts down
           to the icsAlarmTime.  By default, the alarm sound is the terminal
           bell, but on some systems you can change it to a sound file using
           the soundIcsAlarm option; see below.

      Colorize Messages
           Ticking this options causes various types of ICS messages do be
           displayed with different foreground or background colors in the
           console.  The colors can be individually selected for each type,
           through the accompanying text edits.

      Summons a dialog where you can set options important for playing
      automatic matches between two chess programs (e.g. by using the
      `Machine Match' menu item in the `Mode' menu).

      Tournament file
           To run a tournament, XBoard needs a file to record its progress,
           so it can resume the tourney when it is interrupted.  When you
           want to conduct anything more complex than a simple two-player
           match with the currently loaded engines, (i.e. when you select a
           list of participants), you must not leave this field blank. When
           you enter the name of an existing tournament file, XBoard will
           ignore all other input specified in the dialog, and will take
           them from that tournament file.  This resumes an interrupted
           tournament, or adds another XBoard agent playing games for it to
           those that are already doing so.  Specifying a not-yet-existing
           file will cause XBoard to create it, according to the tournament
           parameters specified in the rest of the dialog, before it starts
           the tournament on OK. Provided that you specify
           participants; without participants no tournament file will be
           made, but other entered values (e.g. for the file with opening
           positions) will take effect. Default: configured by the
           `defaultTourneyName' option.

      Sync after round
      Sync after cycle
           The sync options, when on, will cause WinBoard to refrain from
           starting games of the next round or cycle before all games of the
           previous round or cycle are finished.  This guarantees correct
           ordering in the games file, even when multiple XBoard instances
           are concurrently playing games for the same tourney.  Default:
           sync after cycle, but not after round.



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      Select Engine
      Tourney participants
           With the Select Engine drop-down list you can pick an engine from
           your list of installed engines in the settings file, to be added
           to the tournament. The engines selected so far will be listed in
           the Tourney participants memo. The latter is a normal text
           edit, so you can use normal text-editing functions to delete
           engines you selected by accident, or change their order. Do not
           type names yourself there, because names that do not exactly
           match one of the names from the drop-down list will lead to
           undefined behavior.

      Tourney type
           Here you can specify the type of tournament you want. XBoards
           intrinsic tournament manager support round-robins (type = 0),
           where each participant plays every other participant, and
           (multi-)gauntlets, where one (or a few) so-called gauntlet
           engines play an independent set of opponents. In the latter
           case, you specify the number of gauntlet engines. E.g. if you
           specified 10 engines, and tourney type = 2, the first 2 engines
           each play the remaining 8. A value of -1 instructs XBoard to play
           Swiss; for this to work an external pairing engine must be
           specified through the `pairingEngine' option.  Each Swiss round
           will be considered a tourney cycle in that case.  Default:0

      Number of tourney cycles
      Default number of Games
           You can specify tourneys where every two opponents play each
           other multiple times. Such multiple games can be played in a row,
           as specified by the number of games per pairing, or by
           repeating the entire tournament schedule a number of times
           (specified by the number of tourney cycles). The total
           number of times two engine meet will be the product of these two.
           Default is 1 cycle; the number of games per pairing is the same
           as the default number of match games, stored in your settings
           file through the `defaultMatchGames' option.

      Save Tourney Games
           File where the tournament games are saved (duplicate of the item
           in the `Save Game Options').

      Game File with Opening Lines
      File with Start Positions
      Game Number
      Position Number
      Rewind Index after
           These items optionally specify the file with move sequences or
           board positions the tourney games should start from.  The
           corresponding numbers specify the number of the game or position
           in the file.  Here a value -1 means automatic stepping through
           all games on the file, -2 automatic stepping every two games.



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           The Rewind-Index parameter causes a stepping index to reset to
           one after reaching a specified value.  A setting of -2 for the
           game number will also be effective in a tournament without
           specifying a game file, but playing from the GUI book instead.
           In this case the first (odd) games will randomly select from the
           book, but the second (even) games will select the same moves from
           the book as the previous game.  (Note this leads to the same
           opening only if both engines use the GUI book!) Default: No game
           or position file will be used. The default index if such a file
           is used is 1.

      Disable own engine bools be default
           Setting this option reverses the default situation for use of the
           GUI opening book in tournaments from what it normally is, namely
           not using it.  So unless the engine is installed with an option
           to explicitly specify it should not use the GUI book (i.e. `-
           firstHasOwnBookUCI true'), it will be made to use the GUI book.

      Replace Engine
      Upgrade Engine
           With these two buttons you can alter the participants of an
           already running tournament.  After opening the Match Options
           dialog on an XBoard that is playing for the tourney, you will see
           all the tourney parameters in the dialog fields.  You can then
           replace the name of one engine by that of another by editing the
           `participants' field.  (But preserve the order of the others!)
           Pressing the button after that will cause the substitution.  With
           the `Upgrade Engine' button the substitution will only affect
           future games.  With `Replace Engine' all games the substituted
           engine has already played will be invalidated, and they will be
           replayed with the substitute engine.  In this latter case the
           engine must not be playing when you do this, but otherwise there
           is no need to pause the tournament play for making a
           substitution.

      Clone Tourney
           Pressing this button after you have specified an existing
           tournament file will copy the contents of the latter to the
           dialog, and then puts the originally proposed name for the
           tourney file back.  You can then run a tourney with the same
           parameters (possibly after changing the proposed name of the
           tourney file for the new tourney) by pressing 'OK'.

      Summons a dialog where you can set the `autoDisplayComment' and
      `autoDisplayTags' options, (which control popups when viewing loaded
      games), and specify the rate at which loaded games are auto-played, in
      seconds per move (which can be a fractional number, like 1.6).  You
      can also set search criteria for determining which games will be
      displayed in the Game List for a multi-game file, and thus be eligible
      for loading:




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      Elo of strongest player
      Elo of weakest player
      year These numeric fields set thresholds (lower limits) on the Elo
           rating of the mentioned player, or the date the game was played.
           Defaults: 0

      Search mode
           This setting determines which positions in a game will be
           considered a match to the position currently displayed in the
           board window when you press the `find position' button in the
           Game List.  You can search for an exact match, a position that
           has all shown material in the same place, but might contain
           additional material, a position that has all Pawns in the same
           place, but can have the shown material anywhere, a position
           that     can have all shown material anywhere, or a position that
           has material between certain limits anywhere.  For the latter you
           have to place the material that must be present in the four
           lowest ranks of the board, and optional additional material in
           the four highest ranks of the board.  You can request the
           optional material to be balanced.  The `narrow' button is similar
           in fuction to the `find position' button, but only searches in
           the already selected games, rather than the complete game file,
           and can thus be used to refine a search based on multiple
           criteria.

      number of consecutive positions
           When you are searching by material, rather than for an exact
           match, this parameter indicates forhowmany consecutive game
           positions the same amount of material must be on the board before
           it is considered a match.

      Also match reversed colors
      Also match left-right flipped position
           When looking for matching positions rather than by material,
           these settings determine whether mirror images (in case of a
           vertical flip in combination with color reversal) will be also
           considered a match.  The left-right flipping is only useful after
           all castling rights have expired (or in Xiangqi).

      Summons a dialog where you can specify the files on which XBoard
      should automatically save any played or entered games, (the
      `saveGameFile' option), or the final position of such games (the
      `savePositionfile' option).  You can also select 'auto-save' without a
      file name, in which case XBoard will prompt the user for a file name
      after each game.  In ICS mode you can limit the auto-saving to your
      own games (i.e. suppress saving of observed games).  You can also set
      the default value for the PGN Event tag that will be used for each new
      game you start.  Various options for the format of the game can be
      specified as well, such as whether scores and depths of engine games
      should be saved as comments, and if a tag with info about the score
      with which the engine came out of book should be included.  For Chess,



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      always set the format to PGN, rather than "old save stye"!

      Pops up a dialog where you can select the PGN tags that should appear
      on the lines in the game list, and their order.

      Summons a dialog where you can specify the sounds that should
      accompany various events that can occur XBoard.  Most events are only
      relevant to ICS play, but the move sound is an important exception.
      For each event listed in the dialog, you can select a standard sound
      from a menu.  You can also select a user-supplied sound file, by
      typing its name into the designated text-edit field first, and then
      selecting "Above WAV File" from the menu for the event.  A dummy event
      has been provided for trying out the sounds with the "play" button
      next to it.  The directory with standard sounds, and the external
      program for playing the sounds can be specified too, but normally you
      would not touch these once XBoard is properly installed.  When a move
      sound other than 'None' is selected, XBoard alerts you by playing that
      sound after each of your opponent's moves (or after every move if you
      are observing a game on the Internet Chess Server).  The sound is not
      played after moves you make or moves read from a saved game file.

      Selecting this menu item causes the current XBoard settings to be
      written to the settings file, so they will also apply in future
      sessions.  Note that some settings are 'volatile', and are not saved,
      because XBoard considers it too unlikely that you want those to apply
      next time.  In particular this applies to the Chess program names, and
      all options giving information on those Chess programs (such as their
      directory, if they have their own opening book, if they are UCI or
      native XBoard), or the variant you are playing.  Such options would
      still be understood when they appear in the settings file in case they
      were put there with the aid of a text editor, but they would disappear
      from the file as soon as you save the settings.

      Note that XBoard no longer pays attention to options values specified
      in the .Xresources file.  (Specifying key bindings there will still
      work, though.) To alter the default of volatile options, you can use
      the following method: Rename your ~/.xboardrc settings file (to
      ~/.yboardrc, say), and create a new file ~/.xboardrc, which only
      contains the options

          -settingsFile  ~/.yboardrc
          -saveSettingsFile  ~/.yboardrc

      This will cause your settings to be saved on ~/.yboardrc in the
      future, so that ~/.xboardrc is no longer overwritten.  You can then
      safely specify volatile options in ~/.xboardrc, either before or after
      the settingsFile options.  Note that when you specify persistent
      options after the settingsFile options in ~/.xboardrc, you will
      essentially turn them into volatile options with the specified value
      as default, because that value will overrule the value loaded from the
      settings file (being read later).



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      Setting this option has no immediate effect, but causes the settings
      to be saved when you quit XBoard. What happens then is otherwise
      identical to what happens when you use select "Save Settings Now", see
      there.


    Help Menu
      Info XBoard
           Displays the XBoard documentation in info format.  For this
           feature to work, you must have the GNU info program installed on
           your system, and the file `xboard.info' must either be present in
           the current working directory, or have been installed by the
           `make install' command when you built XBoard.

      Man XBoard
           Displays the XBoard documentation in man page format.  The `F1'
           key is a keyboard equivalent.  For this feature to work, the file
           `xboard.6' must have been installed by the `make install' command
           when you built XBoard, and the directory it was placed in must be
           on the search path for your system's `man' command.

      About XBoard
           Shows the current XBoard version number.

    Other Shortcut Keys
      Show Last Move
           By hitting `Enter' the last move will be re-animated.

      Load Next Game
           Loads the next game from the last game record file you loaded.
           The `Alt+PgDn' key triggers this action.

      Load Previous Game
           Loads the previous game from the last game record file you
           loaded.  The `Alt+PgUp' key triggers this action.  Not available
           if the last game was loaded from a pipe.

      Reload Same Game
           Reloads the last game you loaded.  Not available if the last game
           was loaded from a pipe.  Currently no keystroke is assigned to
           this ReloadGameProc.

      Reload Same Position
           Reloads the last position you loaded.  Not available if the last
           position was loaded from a pipe.  Currently no keystroke is
           assigned to this ReloadPositionProc.

      You can add or remove shortcut keys using the X resources
      `form.translations'. Here is an example of what would go in your
      `.Xresources' file:




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          XBoard*form.translations: \
            Shift<Key>?: AboutGameProc() \n\
            <Key>y: AcceptProc() \n\
            <Key>n: DeclineProc() \n\
            <Key>i: NothingProc()

      Binding a key to `NothingProc' makes it do nothing, thus removing it
      as a shortcut key. The XBoard commands that can be bound to keys are:

          AbortProc, AboutGameProc, AboutProc, AcceptProc, AdjournProc,
          AlwaysQueenProc, AnalysisModeProc, AnalyzeFileProc,
          AnimateDraggingProc, AnimateMovingProc, AutobsProc, AutoflagProc,
          AutoflipProc, AutoraiseProc, AutosaveProc, BackwardProc,
          BlindfoldProc, BookProc, CallFlagProc, CopyGameProc, CopyPositionProc,
          DebugProc, DeclineProc, DrawProc, EditCommentProc, EditGameProc,
          EditPositionProc, EditTagsProc, EnterKeyProc, FlashMovesProc,
          FlipViewProc, ForwardProc, GetMoveListProc, HighlightLastMoveProc,
          HintProc, IcsAlarmProc, IcsClientProc, IcsInputBoxProc,
          InfoProc, LoadGameProc, LoadNextGameProc, LoadNextPositionProc,
          LoadPositionProc, LoadPrevGameProc, LoadPrevPositionProc,
          LoadSelectedProc, MachineBlackProc, MachineWhiteProc, MailMoveProc,
          ManProc, MoveNowProc, MoveSoundProc, NothingProc, OldSaveStyleProc,
          PasteGameProc, PastePositionProc, PauseProc, PeriodicUpdatesProc,
          PonderNextMoveProc, PopupExitMessageProc, PopupMoveErrorsProc,
          PremoveProc, QuietPlayProc, QuitProc, ReloadCmailMsgProc,
          ReloadGameProc, ReloadPositionProc, RematchProc, ResetProc,
          ResignProc, RetractMoveProc, RevertProc, SaveGameProc,
          SavePositionProc, ShowCoordsProc, ShowGameListProc, ShowThinkingProc,
          StopExaminingProc, StopObservingProc, TestLegalityProc, ToEndProc,
          ToStartProc, TrainingProc, TruncateGameProc, and TwoMachinesProc.


 OPTIONS
      This section documents the command-line options to XBoard.  You can
      set these options in two ways: by typing them on the shell command
      line you use to start XBoard, or by editing the settings file (usually
      ~/.xboardrc) to alter the value of the setting that was saved there.
      Some of the options cannot be changed while XBoard is running; others
      set the initial state of items that can be changed with the Options
      menu.

      Most of the options have both a long name and a short name. To turn a
      boolean option on or off from the command line, either give its long
      name followed by the value true or false (`-longOptionName true'), or
      give just the short name to turn the option on (`-opt'), or the short
      name preceded by `x' to turn the option off (`-xopt'). For options
      that take strings or numbers as values, you can use the long or short
      option names interchangeably.






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    Chess Engine Options
      -tc or -timeControl minutes[:seconds]
           Each player begins with his clock set to the `timeControl'
           period.  Default: 5 minutes.  The additional options
           `movesPerSession' and `timeIncrement' are mutually exclusive.

      -mps or -movesPerSession moves
           When both players have made `movesPerSession' moves, a new
           `timeControl' period is added to both clocks.  Default: 40 moves.

      -inc or -timeIncrement seconds
           If this option is specified, `movesPerSession' is ignored.
           Instead, after each player's move, `timeIncrement' seconds are
           added to his clock. Use `-inc 0' if you want to require the
           entire game to be played in one `timeControl' period, with no
           increment.  Default: -1, which specifies `movesPerSession' mode.

      -clock/-xclock or -clockMode true/false
           Determines whether or not to display the chess clocks. If
           clockMode is false, the clocks are not shown, but the side that
           is to play next is still highlighted. Also, unless `searchTime'
           is set, the chess engine still keeps track of the clock time and
           uses it to determine how fast to make its moves.

      -st or -searchTime minutes[:seconds]
           Tells the chess engine to spend at most the given amount of time
           searching for each of its moves. Without this option, the chess
           engine chooses its search time based on the number of moves and
           amount of time remaining until the next time control.  Setting
           this option also sets clockMode to false.

      -depth or -searchDepth number
           Tells the chess engine to look ahead at most the given number of
           moves when searching for a move to make. Without this option, the
           chess engine chooses its search depth based on the number of
           moves and amount of time remaining until the next time control.
           With the option, the engine will cut off its search early if it
           reaches the specified depth.

      -firstNPS number
      -secondNPS number
           Tells the chess engine to use an internal time standard based on
           its node count, rather then wall-clock time, to make its timing
           decisions. The time in virtual seconds should be obtained by
           dividing the node count through the given number, like the number
           was a rate in nodes per second. Xboard will manage the clocks in
           accordance with this, relying on the number of nodes reported by
           the engine in its thinking output. If the given number equals
           zero, it can obviously not be used to convert nodes to seconds,
           and the time reported by the engine is used to decrement the
           XBoard clock in stead. The engine is supposed to report in CPU



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           time it uses, rather than wall-clock time, in this mode. This
           option can provide fairer conditions for engine-engine matches on
           heavily loaded machines, or with very fast games (where the wall
           clock is too inaccurate). `showThinking' must be on for this
           option to work. Default: -1 (off).  Not many engines might
           support this yet!

      -firstTimeOdds factor
      -secondTimeOdds factor
           Reduces the time given to the mentioned engine by the given
           factor. If pondering is off, the effect is indistinguishable from
           what would happen if the engine was running on an n-times slower
           machine. Default: 1.

      -timeOddsMode mode
           This option determines how the case is handled where both engines
           have a time-odds handicap. If mode=1, the engine that gets the
           most time will always get the nominal time, as specified by the
           time-control options, and its opponent's time is renormalized
           accordingly. If mode=0, both play with reduced time. Default: 0.

      -hideThinkingFromHuman true/false
           Controls the Hide Thinking option. See Options Menu. Default:
           true.  (Replaces the Show-Thinking option of older xboard
           versions.)

      -thinking/-xthinking or -showThinking true/false
           Forces the engine to send thinking output to xboard. Used to be
           the only way to control if thinking output was displayed in older
           xboard versions, but as the thinking output in xboard 4.3 is also
           used for several other purposes (adjudication, storing in PGN
           file) the display of it is now controlled by the new option Hide
           Thinking. See Options Menu. Default: false.  (But if xboard needs
           the thinking output for some purpose, it makes the engine send it
           despite the setting of this option.)

      -ponder/-xponder or -ponderNextMove true/false
           Sets the Ponder Next Move menu option. See Options Menu. Default:
           true.

      -smpCores number
           Specifies the maximum number of CPUs an SMP engine is allowed to
           use.  Only works for engines that support the XBoard/WinBoard-
           protocol cores feature.

      -mg or -matchGames n
           Automatically runs an n-game match between two chess engines,
           with alternating colors.  If the `loadGameFile' or
           `loadPositionFile' option is set, XBoard starts each game with
           the given opening moves or the given position; otherwise, the
           games start with the standard initial chess position.  If the



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           `saveGameFile' option is set, a move record for the match is
           appended to the specified file. If the `savePositionFile' option
           is set, the final position reached in each game of the match is
           appended to the specified file. When the match is over, XBoard
           displays the match score and exits. Default: 0 (do not run a
           match).

      -mm/-xmm or -matchMode true/false
           Setting `matchMode' to true is equivalent to setting `matchGames'
           to 1.

      -sameColorGames n
           Automatically runs an n-game match between two chess engines,
           without alternating colors.  Otherwise the same applies as for
           the `-matchGames' option, over which it takes precedence if both
           are specified. (See there.) Default: 0 (do not run a match).

      -fcp or -firstChessProgram program
           Name of first chess engine.  Default: `Fairy-Max'.

      -scp or -secondChessProgram program
           Name of second chess engine, if needed.  A second chess engine is
           started only in Two Machines (match) mode.  Default: `Fairy-Max'.

      -fe or -firstEngine nickname
           This is an alternative to the `fcp' option for specifying the
           first engine, for engines that were already configured (using the
           `Load Engine' dialog) in XBoard's settings file.  It will not
           only retrieve the real name of the engine, but also all options
           configured with it.  (E.g. if it is UCI, whether it should use
           book.)

      -se or -secondEngine nickname
           As `fe', but for the second engine.

      -fb/-xfb or -firstPlaysBlack true/false
           In games between two chess engines, firstChessProgram normally
           plays white.  If this option is true, firstChessProgram plays
           black.  In a multi-game match, this option affects the colors
           only for the first game; they still alternate in subsequent
           games.

      -fh or -firstHost host
      -sh or -secondHost host
           Hosts on which the chess engines are to run. The default for each
           is `localhost'. If you specify another host, XBoard uses `rsh' to
           run the chess engine there. (You can substitute a different
           remote shell program for rsh using the `remoteShell' option
           described below.)





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      -fd or -firstDirectory dir
      -sd or -secondDirectory dir
           Working directories in which the chess engines are to be run.
           The default is "", which means to run the chess engine in the
           same working directory as XBoard itself.  (See the CHESSDIR
           environment variable.) This option is effective only when the
           chess engine is being run on the local host; it does not work if
           the engine is run remotely using the -fh or -sh option.

      -initString string or -firstInitString
      -secondInitString string
           The string that is sent to initialize each chess engine for a new
           game.  Default:

               new
               random

           Setting this option from the command line is tricky, because you
           must type in real newline characters, including one at the very
           end.  In most shells you can do this by entering a `\' character
           followed by a newline. Using the character sequence `\n' in the
           string should work too, though.

           If you change this option, don't remove the `new' command; it is
           required by all chess engines to start a new game.

           You can remove the `random' command if you like; including it
           causes GNU Chess 4 to randomize its move selection slightly so
           that it doesn't play the same moves in every game.  Even without
           `random', GNU Chess 4 randomizes its choice of moves from its
           opening book.  Many other chess engines ignore this command
           entirely and always (or never) randomize.

           You can also try adding other commands to the initString; see the
           documentation of the chess engine you are using for details.

      -firstComputerString string
      -secondComputerString string
           The string that is sent to the chess engine if its opponent is
           another computer chess engine.  The default is `computer\n'.
           Probably the only useful alternative is the empty string (`'),
           which keeps the engine from knowing that it is playing another
           computer.

      -reuse/-xreuse or -reuseFirst true/false
      -reuse2/-xreuse2 or -reuseSecond true/false
           If the option is false, XBoard kills off the chess engine after
           every game and starts it again for the next game. If the option
           is true (the default), XBoard starts the chess engine only once
           and uses it repeatedly to play multiple games.  Some old chess
           engines may not work properly when reuse is turned on, but



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           otherwise games will start faster if it is left on.

      -firstProtocolVersion version-number
      -secondProtocolVersion version-number
           This option specifies which version of the chess engine
           communication protocol to use.  By default, version-number is 2.
           In version 1, the "protover" command is not sent to the engine;
           since version 1 is a subset of version 2, nothing else changes.
           Other values for version-number are not supported.

      -firstScoreAbs true/false
      -secondScoreAbs true/false
           If this option is set, the score reported by the engine is taken
           to be that in favor of white, even when the engine plays black.
           Important when XBoard uses the score for adjudications, or in PGN
           reporting.

      -niceEngines priority
           This option allows you to lower the priority of the engine
           processes, so that the generally insatiable hunger for CPU time
           of chess engines does not interfere so much with smooth operation
           of XBoard (or the rest of your system). Negative values could
           increase the engine priority, which is not recommended.

      -firstOptions string
      -secondOptions string
           The given string is a comma-separated list of (option name=option
           value) pairs, like the following example: "style=Karpov,blunder
           rate=0". If an option announced by the engine at startup through
           the feature commands of the XBoard/WinBoard protocol matches one
           of the option names (i.e. "style" or "blunder rate"), it would be
           set to the given value (i.e. "Karpov" or 0) through a
           corresponding option command to the engine. This provided that
           the type of the value (text or numeric) matches as well.

      -firstNeedsNoncompliantFEN string
      -secondNeedsNoncompliantFEN string
           The castling rights and e.p. fields of the FEN sent to the
           mentioned engine with the setboard command will be replaced by
           the given string. This can for instance be used to run engines
           that do not understand Chess960 FENs in variant fischerandom, to
           make them at least understand the opening position, through
           setting the string to "KQkq -". (Note you also have to give the
           e.p. field!) Other possible applications are to provide work-
           arounds for engines that want to see castling and e.p. fields in
           variants that do not have castling or e.p. (shatranj, courier,
           xiangqi, shogi) so that XBoard would normally omit them (string =
           "- -"), or to add variant-specific fields that are not yet
           supported by XBoard (e.g. to indicate the number of checks in
           3check).




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      -shuffleOpenings
           Forces shuffling of the opening setup in variants that normally
           have a fixed initial position.  Shufflings are symmetric for
           black and white, and exempt King and Rooks in variants with
           normal castling.  Remains in force until a new variant is
           selected.

    UCI + WB Engine Settings
      -fUCI or -firstIsUCI true/false
      -sUCI or -secondIsUCI true/false
           Indicates if the mentioned engine executable file is an UCI
           engine, and should be run with the aid of the Polyglot adapter
           rather than directly. Xboard will then pass the other UCI options
           and engine name to Polyglot on its command line, according to the
           option `adapterCommand'.

      -fUCCI
      -sUCCI
      -fUSI
      -sUSI
           Options similar to `fUCI' and `sUCI', except that they use the
           indicated engine with the protocol adapter specified in the
           `uxiAdapter' option.  This can then be configured for running an
           UCCI or USI adapter, as the need arises.

      -adapterCommand string
           The string conatins the command that should be issued by XBoard
           to start an engine that is accompanied by the `fUCI' option.  Any
           identifier following a percent sign in the command (e.g. %fcp)
           will be considered the name of an XBoard option, and be replaced
           by the value of that option at the time the engine is started.
           For starting the second engine, any leading "f" or "first" in the
           option name will first be replaced by "s" or "second", before
           finding its value.  Default: 'polyglot -noini -ec "%fcp" -ed
           "%fd"'

      -uxiAdapter string
           Similar to `adapterCommand', but used for engines accompanied by
           the `fUCCI' or `fUSI' option, so you can configure XBoard to be
           ready to handle more than one flavor of non-native protocols.
           Default: ""

      -polyglotDir filename
           Gives the name of the directory in which the Polyglot adapter for
           UCI engines resides.  Default: "".

      -usePolyglotBook true/false
           Specifies if the Polyglot book should be used as GUI book.

      -polyglotBook filename
           Gives the filename of the opening book.  The book is only used



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           when the `usePolyglotBook' option is set to true, and the option
           `firstHasOwnBookUCI' or `secondHasOwnBookUCI' applying to the
           engine is set to false.  The engine will be kept in force mode as
           long as the current position is in book, and XBoard will select
           the book moves for it. Default: "".

      -fNoOwnBookUCI or -firstXBook or -firstHasOwnBookUCI true/false
      -sNoOwnBookUCI or -secondXBook or -secondHasOwnBookUCI true/false
           Indicates if the mentioned engine has its own opening book it
           should play from, rather than using the external book through
           XBoard. Default: depends on setting of the option
           `discourageOwnBooks'.

      -discourageOwnBooks true/false
           When set, newly loaded engines will be assumed to use the GUI
           book, unless they explicitly specify differently.  Otherwise they
           will be assumed to not use the GUI book, unless the specify
           differently (e.g. with `firstXBook').  Default: false.

      -bookDepth n
           Limits the use of the GUI book to the first n moves of each side.
           Default: 12.

      -bookVariation n
           A value n from 0 to 100 tunes the choice of moves from the GUI
           books from totally random to best-only. Default: 50

      -mcBookMode
           When this volatile option is specified, the probing algorithm of
           the GUI book is altered to always select the move that is most
           under-represented based on its performance.  When all moves are
           played in approximately the right proportion, a book miss will be
           reported, to give the engine opportunity to explore a new move.
           In addition score of the moves will be kept track of during the
           session in a book buffer.  By playing an match in this mode, a
           book will be built from scratch.  The only output are the saved
           games, which can be converted to an actual book later, with the
           `Save Games as Book' command.  This command can also be used to
           pre-fill the book buffer before adding new games based on the
           probing algorithm.

      -fn string or -firstPgnName string
      -sn string or -secondPgnName string
           Indicates the name that should be used for the engine in PGN tags
           of engine-engine games.  Intended to allow you to install verions
           of the same engine with different settings, and still distinguish
           them.  Default: "".

      -defaultHashSize n
           Sets the size of the hash table to n MegaBytes. Together with the
           EGTB cache size this number is also used to calculate the memory



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           setting of XBoard/WinBoard engines, for those that support the
           memory feature of the XBoard/WinBoard protocol. Default: 64.

      -defaultCacheSizeEGTB n
           Sets the size of the EGTB cache to n MegaBytes. Together with the
           hash-table size this number is also used to calculate the memory
           setting of XBoard/WinBoard engines, for those that support the
           memory feature of the XBoard/WinBoard protocol. Default: 4.

      -defaultPathEGTB filename
           Gives the name of the directory where the end-game tablebases are
           installed, for UCI engines.  Default: "/usr/local/share/egtb".

      -egtFormats string
           Specifies which end-game tables are installed on the computer,
           and where. The argument is a comma-separated list of format
           specifications, each specification consisting of a format name, a
           colon, and a directory path name, e.g.
           "nalimov:/usr/local/share/egtb". If the name part matches that of
           a format that the engine requests through a feature command,
           xboard will relay the path name for this format to the engine
           through an egtpath command. One egtpath command for each matching
           format will be sent. Popular formats are "nalimov" DTM tablebases
           and "scorpio" bitbases.  Default: "".

      -firstChessProgramNames={names}
           This option lets you customize the drop-down list of chess engine
           names that appears in the `Load Engine' and `Match Options'
           dialog. It consists of a list of strings, one per line. When an
           engine is loaded, the corresponding line is prefixed with "-fcp
           ", and processed like it appeared on the command line.  That
           means that apart from the engine command, it can contain any list
           of XBoard options you want to use with this engine.  (Commonly
           used options here are -fd, -firstXBook, -fUCI, -variant.)

           The value of this option is gradually built as you load new
           engines through the `Load Engine' menu dialog, with `Add to list'
           ticked. To change it, edit your settings file with a plain text
           editor.

    Tournament options
      -defaultMatchGames n
           Sets the number of games that will be used for a match between
           two engines started from the menu to n. Also used as games per
           pairing in other tournament formats.  Default: 10.

      -matchPause n
           Specifies the duration of the pause between two games of a match
           or tournament between engines as n milliseconds.  Especially
           engines that do not support ping need this option, to prevent
           that the move they are thinking on when an opponent unexpectedly



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           resigns will be counted for the next game, (leading to illegal
           moves there).  Default: 10000.

      -tf filename or -tourneyFile filename
           Specifies the name of the tournament file used in match mode to
           conduct a multi-player tournament. This file is a special
           settings file, which stores the description of the tournament
           (including progress info), through normal options (e.g. for time
           control, load and save files), and through some special-purpose
           options listed below.

      -tt number or -tourneyType number
           Specifies the type of tourney: 0 = round-robin, N>0 = (multi-
           )gauntlet with N gauntlet engines, -1 = Swiss through external
           pairing engine. Volatile option, but stored in tourney file.

      -cy number or -tourneyCycles number
           Specifies the number of cycles in a tourney. Volatile option, but
           stored in tourney file.

      -participants list
           The list is a multi-line text string that specifies engines
           occurring in the `firstChesProgramNames' list in the settings
           file by their (implied or explicitly given) nicknames, one engine
           per line. The mentioned engines will play in the tourney.
           Volatile option, but stored in tourney file.

      -results string
           The string of +=- characters lists the result of all played games
           in a toruney. Games currently playing are listed as *, while a
           space indicates a game that is not yet played or playing .
           Volatile option, but stored in tourney file.

      -defaultTourneyName string
           Specifies the name of the tournament file XBoard should propose
           when the `Match Options' dialog is opened. Any %y, %M, %d, %h,
           %m, %s in the string are replaced by the current year, month, day
           of the month, hours, minutes, seconds of the current time,
           respectively, as two-digit number. A %Y would be replaced by the
           year as 4-digit number. Default: empty string.

      -pairingEngine filename
           Specifies the external program to be used to pair the
           participants in Swiss tourneys. XBoard communicates with this
           engine in the same way as it communicates with Chess engines. The
           only commands sent to the pairing engine are results N
           string, (where N is the number of participants, and string the
           results so far in the format of the results option), and
           pairing N, (where N is the number of the tourney game). To
           the latter the pairing engine should answer with A-B, where
           A and B are participant numbers (in the range 1-N). (There should



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           be no reply to the results command.) Default: empty string.

      -afterGame string
      -afterTourney string
           When non-empty, the given string will be executed as a system
           command after each tournament game, orafterthe tourney completes,
           respectively.  This can be used, for example, to autmatically run
           a cross-table generator on the PGN file where games are saved, to
           update the tourney standings.  Default: ""

      -syncAfterRound true/false
      -syncAfterCycle true/false
           Controls whether different instances of XBoard concurrently
           running the same tournament will wait for each other.  Defaults:
           sync after cycle, but not after round.

      -seedBase number
           Used to store the seed of the pseudo-random-number generator in
           the tourneyFile, so that separate instances of XBoard working on
           the same tourney can take coherent 'random' decisions, such as
           picking an opening for a given game number.

    ICS options
      -ics/-xics or -internetChessServerMode true/false
           Connect with an Internet Chess Server to play chess against its
           other users, observe games they are playing, or review games that
           have recently finished. Default: false.

      -icshost or -internetChessServerHost host
           The Internet host name or address of the chess server to connect
           to when in ICS mode. Default: `chessclub.com'.  Another popular
           chess server to try is `freechess.org'.  If your site doesn't
           have a working Internet name server, try specifying the host
           address in numeric form. You may also need to specify the numeric
           address when using the icshelper option with timestamp or
           timeseal (see below).

      -icsport or -internetChessServerPort port-number
           The port number to use when connecting to a chess server in ICS
           mode. Default: 5000.

      -icshelper or -internetChessServerHelper prog-name
           An external helper program used to communicate with the chess
           server.  You would set it to "timestamp" for ICC (chessclub.com)
           or "timeseal" for FICS (freechess.org), after obtaining the
           correct version of timestamp or timeseal for your computer.  See
           "help timestamp" on ICC and "help timeseal" on FICS.  This option
           is shorthand for `-useTelnet -telnetProgram program'.

      -telnet/-xtelnet or -useTelnet true/false
           This option is poorly named; it should be called useHelper.  If



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           set to true, it instructs XBoard to run an external program to
           communicate with the Internet Chess Server. The program to use is
           given by the telnetProgram option.  If the option is false (the
           default), XBoard opens a TCP socket and uses its own internal
           implementation of the telnet protocol to communicate with the
           ICS. See Firewalls.

      -telnetProgram prog-name
           This option is poorly named; it should be called helperProgram.
           It gives the name of the telnet program to be used with the
           `gateway' and `useTelnet' options.  The default is `telnet'. The
           telnet program is invoked with the value of
           `internetChessServerHost' as its first argument and the value of
           `internetChessServerPort' as its second argument.  See Firewalls.

      -gateway host-name
           If this option is set to a host name, XBoard communicates with
           the Internet Chess Server by using `rsh' to run the
           `telnetProgram' on the given host, instead of using its own
           internal implementation of the telnet protocol. You can
           substitute a different remote shell program for `rsh' using the
           `remoteShell' option described below.  See Firewalls.

      -internetChessServerCommPort or -icscomm dev-name
           If this option is set, XBoard communicates with the ICS through
           the given character I/O device instead of opening a TCP
           connection.  Use this option if your system does not have any
           kind of Internet connection itself (not even a SLIP or PPP
           connection), but you do have dial-up access (or a hardwired
           terminal line) to an Internet service provider from which you can
           telnet to the ICS.

           The support for this option in XBoard is minimal. You need to set
           all communication parameters and tty modes before you enter
           XBoard.

           Use a script something like this:

               stty raw -echo 9600 > /dev/tty00
               xboard -ics -icscomm /dev/tty00

           Here replace `/dev/tty00' with the name of the device that your
           modem is connected to. You might have to add several more options
           to these stty commands. See the man pages for `stty' and `tty' if
           you run into problems. Also, on many systems stty works on its
           standard input instead of standard output, so you have to use `<'
           instead of `>'.

           If you are using linux, try starting with the script below.
           Change it as necessary for your installation.




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               #!/bin/sh -f
               # configure modem and fire up XBoard

               # configure modem
               (
                 stty 2400 ; stty raw ; stty hupcl ; stty -clocal
                 stty ignbrk ; stty ignpar ; stty ixon ; stty ixoff
                 stty -iexten ; stty -echo
               ) < /dev/modem
               xboard -ics -icscomm /dev/modem

           After you start XBoard in this way, type whatever commands are
           necessary to dial out to your Internet provider and log in.  Then
           telnet to ICS, using a command like `telnet chessclub.com 5000'.
           Important: See the paragraph below about extra echoes, in
           Limitations.

      -icslogon or -internetChessServerLogonScript file-name
           Whenever XBoard connects to the Internet Chess Server, if it
           finds a file with the name given in this option, it feeds the
           file's contents to the ICS as commands. The default file name is
           `.icsrc'.  Usually the first two lines of the file should be your
           ICS user name and password.  The file can be either in $CHESSDIR,
           in XBoard's working directory if CHESSDIR is not set, or in your
           home directory.

      -msLoginDelay delay
           If you experience trouble logging on to an ICS when using the `-
           icslogon' option, inserting some delay between characters of the
           logon script may help. This option adds `delay' milliseconds of
           delay between characters. Good values to try are 100 and 250.

      -icsinput/-xicsinput or -internetChessServerInputBox true/false
           Sets the ICS Input Box menu option. See Mode Menu. Default:
           false.

      -autocomm/-xautocomm or -autoComment true/false
           Sets the Auto Comment menu option. See Options Menu. Default:
           false.

      -autoflag/-xautoflag or -autoCallFlag true/false
           Sets the Auto Flag menu option.  See Options Menu. Default:
           false.

      -autobs/-xautobs or -autoObserve true/false
           Sets the Auto Observe menu option.  See Options Menu. Default:
           false.

      -autoKibitz
           Enables kibitzing of the engines last thinking output (depth,
           score, time, speed, PV) before it moved to the ICS, in zippy



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           mode. The option `showThinking' must be switched on for this
           option to work.  Also diverts similar kibitz information of an
           opponent engine that is playing you through the ICS to the
           engine-output window, as if the engine was playing locally.

      -seekGraph true/false or -sg
           Enables displaying of the seek graph by left-clicking the board
           when you are logged on to an ICS and currently idle.  The seek
           graph show all players currently seeking games on the ICS,
           plotted according to their rating and the time control of the
           game they seek, in three different colors (for rated, unrated and
           wild games).  Computer ads are displayed as squares, human ads
           are dots.  Default: false.

      -autoRefresh true/false
           Enables automatic updating of the seek graph, by having the ICS
           send a running update of all newly placed and removed seek ads.
           This consumes a substantial amount of communication bandwidth,
           and is only supported for FICS and ICC.  Default: false.

      -backgroundObserve true/false
           When true, boards sent to you by the ICS from other games while
           you are playing (e.g. because you are observing them) will not be
           automatically displayed.  Only a summary of time left and
           material of both players will appear in the message field above
           the board.  XBoard will remember the last board it has received
           this way, and will display it in stead of the position in your
           own game when you press the right mouse button.  No other
           information is stored on such games observed in the background;
           you cannot save such a game later, or step through its moves.
           This feature is provided solely for the benefit of bughouse
           players, to enable them to peek at their partner's game without
           the need to logon twice.  Default: false.

      -dualBoard true/false
           In combination with -backgroundObserve true, this option will
           display the board of the background game side by side with that
           of your own game, so you can have it in view permanently.  Any
           board or holdings info coming in will be displayed on the
           secondary board immediately.  This feature is still experimental
           and largely unfinished.  There is no animation or highlighting of
           moves on the secondary board.  Default: false.

      -disguisePromotedPieces true/false
           When set promoted Pawns in crazyhouse/bughouse are displayed
           identical to primordial pieces of the same type, rather than
           distinguishable.  Default: true.

      -moves/-xmoves or -getMoveList true/false
           Sets the Get Move List menu option.  See Options Menu.  Default:
           true.



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      -alarm/-xalarm or -icsAlarm true/false
           Sets the ICS Alarm menu option.  See Options Menu. Default: true.

      -icsAlarmTime ms
           Sets the time in milliseconds for the ICS Alarm menu option.  See
           Options Menu. Default: 5000.

      lowTimeWarning true/false
           Controls a color change of the board as a warning your time is
           running out.  See Options Menu. Default: false.

      -pre/-xpre or -premove true/false
           Sets the Premove menu option. See Options Menu. Default: true.

      -prewhite/-xprewhite or -premoveWhite
      -preblack/-xpreblack or -premoveBlack
      -premoveWhiteText string
      -premoveBlackText string
           Set the menu options for specifying the first move for either
           color. See Options Menu. Defaults: false and empty strings, so no
           pre-moves.

      -quiet/-xquiet or -quietPlay true/false
           Sets the Quiet Play menu option.  See Options Menu.  Default:
           false.

      -colorizeMessages or -colorize/-xcolorize
           Setting colorizeMessages to true tells XBoard to colorize the
           messages received from the ICS.  Colorization works only if your
           xterm supports ISO 6429 escape sequences for changing text
           colors.  Default: true.

      -colorShout foreground,background,bold
      -colorSShout foreground,background,bold
      -colorCShout foreground,background,bold
      -colorChannel1 foreground,background,bold
      -colorChannel foreground,background,bold
      -colorKibitz foreground,background,bold
      -colorTell foreground,background,bold
      -colorChallege foreground,background,bold
      -colorRequest foreground,background,bold
      -colorSeek foreground,background,bold
      -colorNormal foreground,background,bold
           These options set the colors used when colorizing ICS messages.
           All ICS messages are grouped into one of these categories: shout,
           sshout, channel 1, other channel, kibitz, tell, challenge,
           request (including abort, adjourn, draw, pause, and takeback), or
           normal (all other messages).

           Each foreground or background argument can be one of the
           following: black, red, green, yellow, blue, magenta, cyan, white,



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           or default.  Here ``default'' means the default foreground or
           background color of your xterm.  Bold can be 1 or 0.  If
           background is omitted, ``default'' is assumed; if bold is
           omitted, 0 is assumed.


      -soundProgram progname
           If this option is set to a sound-playing program that is
           installed and working on your system, XBoard can play sound files
           when certain events occur, listed below.  The default program
           name is "play".  If any of the sound options is set to "$", the
           event rings the terminal bell by sending a ^G character to
           standard output, instead of playing a sound file.  If an option
           is set to the empty string "", no sound is played for that event.

      -soundDirectory directoryname
           This option specifies where XBoard will look for sound files,
           when these are not given as an absolute path name.

      -soundShout filename
      -soundSShout filename
      -soundCShout filename
      -soundChannel filename
      -soundChannel1 filename
      -soundKibitz filename
      -soundTell filename
      -soundChallenge filename
      -soundRequest filename
      -soundSeek filename
           These sounds are triggered in the same way as the colorization
           events described above.  They all default to "", no sound.  They
           are played only if the colorizeMessages is on.  CShout is
           synonymous with SShout.

      -soundMove filename
           This sound is used by the Move Sound menu option.  Default: "$".

      -soundIcsAlarm filename
           This sound is used by the ICS Alarm menu option.  Default: "$".

      -soundIcsWin filename
           This sound is played when you win an ICS game.  Default: "" (no
           sound).

      -soundIcsLoss filename
           This sound is played when you lose an ICS game.  Default: "" (no
           sound).

      -soundIcsDraw filename
           This sound is played when you draw an ICS game.  Default: "" (no
           sound).



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      -soundIcsUnfinished filename
           This sound is played when an ICS game that you are participating
           in is aborted, adjourned, or otherwise ends inconclusively.
           Default: "" (no sound).

    Load and Save options
      -lgf or -loadGameFile file
      -lgi or -loadGameIndex index
           If the `loadGameFile' option is set, XBoard loads the specified
           game file at startup. The file name `-' specifies the standard
           input. If there is more than one game in the file, XBoard pops up
           a menu of the available games, with entries based on their PGN
           (Portable Game Notation) tags.  If the `loadGameIndex' option is
           set to `N', the menu is suppressed and the N th game found in the
           file is loaded immediately.  The menu is also suppressed if
           `matchMode' is enabled or if the game file is a pipe; in these
           cases the first game in the file is loaded immediately.  Use the
           `pxboard' shell script provided with XBoard if you want to pipe
           in files containing multiple games and still see the menu.  If
           the loadGameIndex specifies an index -1, this triggers auto-
           increment of the index in `matchMode', which means that after
           every game the index is incremented by one, causing each game of
           the match to be played from the next game in the file. Similarly,
           specifying an index value of -2 causes the index to be
           incremented every two games, so that each game in the file is
           used twice (with reversed colors).  The `rewindIndex' option
           causes the index to be reset to the first game of the file when
           it has reached a specified value.

      -rewindIndex n
           Causes a position file or game file to be rewound to its
           beginning after n positions or games in auto-increment
           `matchMode'. See `loadPositionIndex' and `loadGameIndex'.
           default: 0 (no rewind).

      -td or -timeDelay seconds
           Time delay between moves during `Load Game' or `Analyze File'.
           Fractional seconds are allowed; try `-td 0.4'. A time delay value
           of -1 tells XBoard not to step through game files automatically.
           Default: 1 second.

      -sgf or -saveGameFile file
           If this option is set, XBoard appends a record of every game
           played to the specified file. The file name `-' specifies the
           standard output.

      -autosave/-xautosave or -autoSaveGames true/false
           Sets the Auto Save menu option.  See Options Menu.  Default:
           false.  Ignored if `saveGameFile' is set.





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      -onlyOwnGames true/false
           Suppresses auto-saving of ICS observed games. Default: false.

      -lpf or -loadPositionFile file
      -lpi or -loadPositionIndex index
           If the `loadPositionFile' option is set, XBoard loads the
           specified position file at startup. The file name `-' specifies
           the standard input. If the `loadPositionIndex' option is set to
           N, the Nth position found in the file is loaded; otherwise the
           first position is loaded.  If the loadPositionIndex specifies an
           index -1, this triggers auto-increment of the index in
           `matchMode', which means that after every game the index is
           incremented by one, causing each game of the match to be played
           from the next position in the file. Similarly, specifying an
           index value of -2 causes the index to be incremented every two
           games, so that each position in the file is used twice (with the
           engines playing opposite colors).  The `rewindIndex' option
           causes the index to be reset to the first position of the file
           when it has reached a specified value.

      -spf or -savePositionFile file
           If this option is set, XBoard appends the final position reached
           in every game played to the specified file. The file name `-'
           specifies the standard output.

      -pgnExtendedInfo true/false
           If this option is set, XBoard saves depth, score and time used
           for each move that the engine found as a comment in the PGN file.
           Default: false.

      -pgnEventHeader string
           Sets the name used in the PGN event tag to string. Default:
           "Computer Chess Game".

      -pgnNumberTag true/false
           Include the (unique) sequence number of a tournament game into
           the saved PGN file as a 'number' tag.  Default: false.

      -saveOutOfBookInfo true/false
           Include the information on how the engine(s) game out of its
           opening book in a special 'annotator' tag with the PGN file.
           Default: true.

      -oldsave/-xoldsave or -oldSaveStyle true/false
           Sets the Old Save Style menu option.  See Options Menu.  Default:
           false.

      -gameListTags string
           The character string lists the PGN tags that should be printed in
           the Game List, and their order. The meaning of the codes is
           e=event, s=site, d=date, o=round, p=players, r=result, w=white



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           Elo, b=black Elo, t=time control, v=variant, a=out-of-book info,
           c=result comment.  Default: "eprd"

      -ini or -settingsFile filename
      -saveSettingsFile filename
      @filename
           When XBoard encounters an option -settingsFile (or -ini for
           short), or @filename, it tries to read the mentioned file, and
           substitutes the contents of it (presumaby more command-line
           options) in place of the option.  In the case of -ini or
           -settingsFile, the name of a successfully read settings file is
           also remembered as the file to use for saving settings
           (automatically on exit, or on user command).  An option of the
           form @filename does not affect saving.  The option
           -saveSettingsFile does specify a name of the file to use for
           saving, without reading any options from it, and is thus also
           effective when the file did not exist yet.  So the settings will
           be saved to the file specified in the last -saveSettingsFile or
           succesfull -settingsFile / -ini command, if any, and in
           /etc/xboard/xboard.conf otherwise.  Usualy the latter is only
           accessible for the system administrator, though, and will be used
           to contain system-wide default setings, amongst which a
           -saveSettingsFile and -settingsFile options to specify a settings
           file accessible to the individual user, such as ~/.xboardrc in
           the user's home directory.

      -saveSettingsOnExit true/false
           Controls saving of options on the settings file.  See Options
           Menu.  Default: true.

    User interface options
      -display
      -geometry
      -iconic
      -name
           These and most other standard Xt options are accepted.

      -noGUI
           Suppresses all GUI functions of XBoard (to speed up automated
           ultra-fast engine-engine games, which you don't want to watch).
           There will be no board or clock updates, no printing of moves,
           and no update of the icon on the task bar in this mode.

      -logoSize N
           This option controls the drawing of player logos next to the
           clocks.  The integer N specifies the width of the logo in pixels;
           the logo height will always be half the width.  When N = 0, no
           logos will be diplayed.  Default: 0.

      -firstLogo imagefile




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      -secondLogo imagefile
           Specify the images to be used as player logos when `logoSize' is
           non-zero, next to the white and black clocks, respectively.

      -autoLogo true/false

      -logoDir filename
           When `autoLogo' is set, XBoard will search for a PNG image file
           with the name of the engine or ICS in the directory specified by
           `logoDir'.

      -recentEngines number
      -recentEngineList list
           When the number is larger than zero, it determines how many
           recently used engines will be appended at the bottom of the
           `Engines' menu.  The engines will be saved in your settings file
           as the option `recentEngineList', by their nicknames, and the
           most recently used one will always be sorted to the top.  If the
           list after that is longer than the specified number, the last one
           is discarded.  Changes in the list will only become visible the
           next session, provided you saved the settings.  Default: 6.

      -oneClickMove true/false
           When set, this option allows you to enter moves by only clicking
           the to- or from-square, when only a single legal move to or from
           that square is possible.  Double-clicking a piece (or clicking an
           already selected piece) will instruct that piece to make the only
           capture it can legally do.  Default: false.

      -movesound/-xmovesound or -ringBellAfterMoves true/false
           Sets the Move Sound menu option.  See Options Menu.  Default:
           false.  For compatibility with old XBoard versions, -bell/-xbell
           are also accepted as abbreviations for this option.

      -exit/-xexit or -popupExitMessage true/false
           Sets the Popup Exit Message menu option.  See Options Menu.
           Default: true.

      -popup/-xpopup or -popupMoveErrors true/false
           Sets the Popup Move Errors menu option.  See Options Menu.
           Default: false.

      -queen/-xqueen or -alwaysPromoteToQueen true/false
           Sets the Always Queen menu option.  See Options Menu.  Default:
           false.

      -sweepPromotions true/false
           Sets the `Almost Always Promote to Queen' menu option. See
           Options Menu.  Default: false.





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      -legal/-xlegal or -testLegality true/false
           Sets the Test Legality menu option.  See Options Menu.  Default:
           true.

      -size or -boardSize (sizeName | n1,n2,n3,n4,n5,n6,n7)
           Determines how large the board will be, by selecting the pixel
           size of the pieces and setting a few related parameters.  The
           sizeName can be one of: Titanic, giving 129x129 pixel pieces,
           Colossal 116x116, Giant 108x108, Huge 95x95, Big 87x87, Large
           80x80, Bulky 72x72, Medium 64x64, Moderate 58x58, Average 54x54,
           Middling 49x49, Mediocre 45x45, Small 40x40, Slim 37x37, Petite
           33x33, Dinky 29x29, Teeny 25x25, or Tiny 21x21.  Xboard installs
           with a set of scalable (svg) piece images, which it scales to any
           of the requested sizes.  The square size can further be
           continuously scaled by sizing the board window, but this only
           adapts the size of the pieces, and has no effect on the width of
           the grid lines or the font choice (both of which would depend on
           he selected boardSize).  The default depends on the size of your
           screen; it is approximately the largest size that will fit
           without clipping.

           You can select other sizes or vary other layout parameters by
           providing a list of comma-separated values (with no spaces) as
           the argument.  You do not need to provide all the values; for any
           you omit from the end of the list, defaults are taken from the
           nearest built-in size.  The value `n1' gives the piece size, `n2'
           the width of the black border between squares, `n3' the desired
           size for the clockFont, `n4' the desired size for the coordFont,
           `n5' the desired size for the messageFont, `n6' the smallLayout
           flag (0 or 1), and `n7' the tinyLayout flag (0 or 1). All
           dimensions are in pixels.  If the border between squares is
           eliminated (0 width), the various highlight options will not
           work, as there is nowhere to draw the highlight.  If smallLayout
           is 1 and `titleInWindow' is true, the window layout is rearranged
           to make more room for the title.  If tinyLayout is 1, the labels
           on the menu bar are abbreviated to one character each and the
           buttons in the button bar are made narrower.

      -overrideLineGap n
           When n >= 0, this forces the width of the black border between
           squares to n pixels for any board size. Mostly used to suppress
           the grid entirely by setting n = 0, e.g. in xiangqi or just
           getting a prettier picture. When n < 0 this the size-dependent
           width of the grid lines is used. Default: -1.

      -coords/-xcoords or -showCoords true/false
           Sets the Show Coords menu option.  See Options Menu.  Default:
           false.  The `coordFont' option specifies what font to use.

      -autoraise/-xautoraise or -autoRaiseBoard true/false
           Sets the Auto Raise Board menu option.  See Options Menu.



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           Default: true.

      -autoflip/-xautoflip or -autoFlipView true/false
           Sets the Auto Flip View menu option.  See Options Menu.  Default:
           true.

      -flip/-xflip or -flipView true/false
           If Auto Flip View is not set, or if you are observing but not
           participating in a game, then the positioning of the board at the
           start of each game depends on the flipView option.  If flipView
           is false (the default), the board is positioned so that the white
           pawns move from the bottom to the top; if true, the black pawns
           move from the bottom to the top.  In any case, the Flip menu
           option (see Options Menu) can be used to flip the board after the
           game starts.

      -title/-xtitle or -titleInWindow true/false
           If this option is true, XBoard displays player names (for ICS
           games) and game file names (for `Load Game') inside its main
           window. If the option is false (the default), this information is
           displayed only in the window banner. You probably won't want to
           set this option unless the information is not showing up in the
           banner, as happens with a few X window managers.

      -buttons/-xbuttons or -showButtonBar True/False
           If this option is False, xboard omits the [<<] [<] [P] [>] [>>]
           button bar from the window, allowing the message line to be
           wider.  You can still get the functions of these buttons using
           the menus or their keyboard shortcuts.  Default: true.

      -evalZoom factor
           The score interval (-1,1) is blown up on the vertical axis of the
           Evaluation Graph by the given factor.  Default: 1

      -evalThreshold n
           Score below n (centiPawn) are plotted as 0 in the Evaluation
           Graph.  Default: 25

      -mono/-xmono or -monoMode true/false
           Determines whether XBoard displays its pieces and squares with
           two colors (true) or four (false). You shouldn't have to specify
           `monoMode'; XBoard will determine if it is necessary.

      -showTargetSquares true/false
           Determines whether XBoard can highlight the squares a piece has
           legal moves to, when you grab that piece with the mouse.
           Default: false.

      -flashCount count
      -flashRate rate




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      -flash/-xflash
           These options enable flashing of pieces when they land on their
           destination square.  `flashCount' tells XBoard how many times to
           flash a piece after it lands on its destination square.
           `flashRate' controls the rate of flashing (flashes/sec).
           Abbreviations: `flash' sets flashCount to 3.  `xflash' sets
           flashCount to 0.  Defaults:  flashCount=0 (no flashing),
           flashRate=5.

      -highlight/-xhighlight or -highlightLastMove true/false
           Sets the Highlight Last Move menu option. See Options Menu.
           Default: false.

      -highlightMoveWithArrow true/false
           Sets the Highlight with Arrow menu option. See Options Menu.
           Default: false.

      -blind/-xblind or -blindfold true/false
           Sets the Blindfold menu option.  See Options Menu.  Default:
           false.

      -periodic/-xperiodic or -periodicUpdates true/false
           Controls updating of current move andnode counts in analysis
           mode. Default: true.

      -fSAN
      -sSAN
           Causes the PV in thinking output of the mentioned engine to be
           converted to SAN before it is further processed.  Warning: this
           might lose engine output not understood by the parser, and uses a
           lot of CPU power.  Default: the PV is displayed exactly as the
           engine produced it.

      -showEvalInMoveHistory true/false
           Controls whether the evaluation scores and search depth of engine
           moves are displayed with the move in the move-history window.
           Default: true.

      -clockFont font
           The font used for the clocks. If the option value is a pattern
           that does not specify the font size, XBoard tries to choose an
           appropriate font for the board size being used.  Default: -*-
           helvetica-bold-r-normal--*-*-*-*-*-*-*-*.

      -coordFont font
           The font used for rank and file coordinate labels if `showCoords'
           is true. If the option value is a pattern that does not specify
           the font size, XBoard tries to choose an appropriate font for the
           board size being used.  Default: -*-helvetica-bold-r-normal--*-
           *-*-*-*-*-*-*.




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      -messageFont font
           The font used for popup dialogs, menus, comments, etc.  If the
           option value is a pattern that does not specify the font size,
           XBoard tries to choose an appropriate font for the board size
           being used.  Default: -*-helvetica-medium-r-normal--*-*-*-
           *-*-*-*-*.

      -fontSizeTolerance tol
           In the font selection algorithm, a nonscalable font will be
           preferred over a scalable font if the nonscalable font's size
           differs by `tol' pixels or less from the desired size.  A value
           of -1 will force a scalable font to always be used if available;
           a value of 0 will use a nonscalable font only if it is exactly
           the right size; a large value (say 1000) will force a nonscalable
           font to always be used if available.  Default: 4.

      -pid or -pieceImageDirectory dir
           This options control what piece images xboard uses.  XBoard will
           look in the specified directory for an image in png or svg format
           for every piece type, with names like BlackQueen.svg,
           WhiteKnight.svg etc.  When neither of these is found (or no valid
           directory is specified) XBoard will use the svg piece that was
           installed with it (from the source-tree directory `svg').  Both
           svg and png images will be scaled by XBoard to the required size,
           but the png pieces lose much in quality when scaled too much.


      -whitePieceColor color
      -blackPieceColor color
      -lightSquareColor color
      -darkSquareColor color
      -highlightSquareColor color
      -preoveHighlightColor color
      -lowTimeWarningColor color
           Colors to use for the pieces, squares, and square highlights.
           Defaults:

               -whitePieceColor       #FFFFCC
               -blackPieceColor       #202020
               -lightSquareColor      #C8C365
               -darkSquareColor       #77A26D
               -highlightSquareColor  #FFFF00
               -premoveHighlightColor #FF0000
               -lowTimeWarningColor   #FF0000

           On a grayscale monitor you might prefer:

               -whitePieceColor       gray100
               -blackPieceColor       gray0
               -lightSquareColor      gray80
               -darkSquareColor       gray60



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               -highlightSquareColor  gray100
               -premoveHighlightColor gray70
               -lowTimeWarningColor   gray70

           The PieceColor options only work properly if the image files
           defining the pieces were pure black & white (possibly anti-
           aliased to produce gray scales and semi-transparancy), like the
           pieces images that come with the install.  Their effect on
           colored pieces is undefined.  The SquareColor option only have an
           effect when no board textures are used.

      -trueColors true/false
           When set, this option suppresses the effect  of the PieceColor
           options mentioned above.  This is recommended for images that are
           already colored.

      -useBoardTexture true/false
      -liteBackTextureFile filename
      -darkBackTextureFile filename
           Indicate the png image files to be used for drawing the board
           squares, and if they should be used rather than using simple
           colors.  The algorithm for cutting squares out of a given bitmap
           is such that the picture is perfectly reproduced when a bitmap
           the size of the complete board is given.  Default: false and ""

      -drag/-xdrag or -animateDragging true/false
           Sets the Animate Dragging menu option. See Options Menu.
           Default: true.

      -animate/-xanimate or -animateMoving true/false
           Sets the Animate Moving menu option. See Options Menu.  Default:
           true.

      -animateSpeed n
           Number of milliseconds delay between each animation frame when
           Animate Moves is on.

      -autoDisplayComment true/false
      -autoDisplayTags true/false
           If set to true, these options cause the window with the move
           comments, and the window with PGN tags, respectively, to pop up
           automatically when such tags or comments are encountered during
           the replaying a stored or loaded game.  Default: true.

      -pasteSelection true/false
           If this option is set to true, the Paste Position and Paste Game
           options paste from the currently selected text.  If false, they
           paste from the clipboard.  Default: false.

      -autoCopyPV true|false
           When this option is set, the position displayed on the board when



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           you terminate a PV walk (initiated by a right-click on board or
           engine-output window) will be automatically put on the clipboard
           as FEN.  Default: false.

      -dropMenu true|false
           This option allows you to emulate old behavior, where the right
           mouse button brings up the (now deprecated) drop menu rather than
           displaying the position at the end of the principal variation.
           Default: False.

      -pieceMenu true|false
           This option allows you to emulate old behavior, where the right
           mouse button brings up the (now deprecated) piece menu in Edit
           Position mode.  From this menu you can select the piece to put on
           the square you clicked to bring up the menu, or select items such
           as `clear board'.  You can also `promote' or `demote' a clicked
           piece to convert it into an unorthodox piece that is not directly
           in the menu, or give the move to `black' or `white'.

      -variations true|false
           When this option is on, you can start new variations in Edit Game
           or Analyze mode by holding the Shift key down while entering a
           move.  When it is off, the Shift key will be ignored.  Default:
           False.

      -appendPV true|false
           When this option is on, right-clicking a PV in the Engine Output
           window will play the first move of that PV in Analyze mode, or as
           many moves as you walk through by moving the mouse.  Default:
           False.

      -absoluteAnalysisScores true|false
           When true, scores on the Engine Output window during analysis
           will be printed from the white point-of-view, rather than the
           side-to-move point-of-view.  Default: False.

      -scoreWhite true|false
           When true, scores will always be printed from the white point-
           of-view, rather than the side-to-move point-of-view.  Default:
           False.

    Adjudication Options
      -adjudicateLossThreshold n
           If the given value is non-zero, XBoard adjudicates the game as a
           loss if both engines agree for a duration of 6 consecutive ply
           that the score is below the given score threshold for that
           engine. Make sure the score is interpreted properly by XBoard,
           using `-firstScoreAbs' and `-secondScoreAbs' if needed. Default:
           0 (no adjudication)





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      -adjudicateDrawMoves n
           If the given value is non-zero, XBoard adjudicates the game as a
           draw if after the given number of moves it was not yet decided.
           Default: 0 (no adjudication)

      -checkMates true/false
           If this option is set, XBoard detects all checkmates and
           stalemates, and ends the game as soon as they occur. Legality-
           testing must be switched on for this option to work.  Default:
           true

      -testClaims true/false
           If this option is set, XBoard verifies all result claims made by
           engines, and those who send false claims will forfeit the game
           because of it. Legality-testing must be switched on for this
           option to work. Default: true

      -materialDraws true/false
           If this option is set, XBoard adjudicates games as draws when
           there is no sufficient material left to inflict a checkmate. This
           applies to KBKB with like bishops (any number, actually), and to
           KBK, KNK and KK. Legality-testing must be switched on for this
           option to work. Default: true

      -trivialDraws true/false
           If this option is set, XBoard adjudicates games as draws that
           cannot be usually won without opponent cooperation. This applies
           to KBKB with unlike bishops, and to KBKN, KNKN, KNNK, KRKR and
           KQKQ. The draw is called after 6 ply into these end-games, to
           allow quick mates that can occur in some exceptional positions to
           be found by the engines. KQKQ does not really belong in this
           category, and might be taken out in the future. (When bitbase-
           based adjudications are implemented.) Legality-testing must be on
           for this option to work. Default: false

      -ruleMoves n
           If the given value is non-zero, XBoard adjudicates the game as a
           draw after the given number of consecutive reversible moves.
           Engine draw claims are always accepted after 50 moves,
           irrespective of the given value of n.

      -repeatsToDraw n
           If the given value is non-zero, xboard adjudicates the game as a
           draw if a position is repeated the given number of times. Engines
           draw claims are always accepted after 3 repeats, (on the 3rd
           occurrence, actually), irrespective of the value of n. Beware
           that positions that have different castling or en-passant rights
           do not count as repeats, XBoard is fully e.p. and castling aware!

    Other options




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      -ncp/-xncp or -noChessProgram true/false
           If this option is true, XBoard acts as a passive chessboard; it
           does not start a chess engine at all. Turning on this option also
           turns off clockMode. Default: false.

      -viewer
      -viewerOptions string
           Presence of the volatile option `viewer' on the command line will
           cause the value of the persistent option `viewerOptions' as
           stored in the settings file to be appended to the command line.
           The `view' option will be used by desktop associations with game
           or position file types, so that `viewerOptions' can be used to
           configure the exact mode XBoard will start in when it should act
           on such a file (e.g. in -ncp mode, or analyzing with your
           favorite engine). The options are also automatically appended
           when Board is invoked with a single argument not being an option
           name, which is then assumed to be the name of a `loadGameFile' or
           (when the name ends in .fen) a `loadPositionFile'.  Default: "-
           ncp -engineOutputUp false -saveSettingsOnExit false".

      -tourneyOptions string
           When XBoard is invoked with a single argument that is a file with
           .trn extension, it will assume this argument to be the value of a
           `tourneyFile' option, and apped the value of the persistent
           option `tourneyOptions' as stored in the settings file to the
           command line.  Thus the value of `tourneyOptions' can be used to
           configure XBoard to automatically start running a tournament when
           it should act on such a file.  Default: "-ncp -mm
           -saveSettingsOnExit false".

      -mode or -initialMode modename
           If this option is given, XBoard selects the given modename from
           the Mode menu after starting and (if applicable) processing the
           loadGameFile or loadPositionFile option. Default: "" (no
           selection). Other supported values are MachineWhite,
           MachineBlack, TwoMachines, Analysis, AnalyzeFile, EditGame,
           EditPosition, and Training.

      -variant varname
           Activates preliminary, partial support for playing chess variants
           against a local engine or editing variant games.  This flag is
           not needed in ICS mode.  Recognized variant names are:

               normal        Normal chess
               wildcastle    Shuffle chess, king can castle from d file
               nocastle      Shuffle chess, no castling allowed
               fischerandom  Fischer Random shuffle chess
               bughouse      Bughouse, ICC/FICS rules
               crazyhouse    Crazyhouse, ICC/FICS rules
               losers        Lose all pieces or get mated (ICC wild 17)
               suicide       Lose all pieces including king (FICS)



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               giveaway      Try to have no legal moves (ICC wild 26)
               twokings      Weird ICC wild 9
               kriegspiel    Opponent's pieces are invisible
               atomic        Capturing piece explodes (ICC wild 27)
               3check        Win by giving check 3 times (ICC wild 25)
               shatranj      An ancient precursor of chess (ICC wild 28)
               xiangqi       Chinese Chess (on a 9x10 board)
               shogi         Japanese Chess (on a 9x9 board & piece drops)
               capablanca    Capablanca Chess (10x8 board, with Archbishop
                             and Chancellor pieces)
               gothic        similar, with a better initial position
               caparandom    An FRC-like version of Capablanca Chess (10x8)
               janus         A game with two Archbishops (10x8 board)
               courier       Medieval intermediate between shatranj and
                             modern Chess (on 12x8 board)
               falcon        Patented 10x8 variant with two Falcon pieces
               berolina      Pawns capture straight ahead, and move diagonal
               cylinder      Pieces wrap around the board edge
               knightmate    King moves as Knight, and vice versa
               super         Superchess (shuffle variant with 4 exo-pieces)
               makruk        Thai Chess (shatranj-like, P promotes on 6th rank)
               spartan       Spartan Chess (black has unorthodox pieces)
               fairy         A catchall variant in which all piece types
                             known to XBoard can participate (8x8)
               unknown       Catchall for other unknown variants

           NOT ALL BOARDSIZES PROVIDE A COMPLETE SET OF BUILT-IN BITMAPS FOR
           ALL UN-ORTHODOX PIECES, though. Only in `boardSize' middling and
           bulky all 22 piece types are provided, while -boardSize petite
           has most of them. Archbishop, Chancellor and Amazon are supported
           in every size from petite to bulky. Kings or Amazons are
           substituted for missing bitmaps. You can still play variants
           needing un-orthodox pieces in other board sizes providing your
           own bitmaps through the `bitmapDirectory' or `pixmapDirectory'
           options.

           In the shuffle variants, XBoard now does shuffle the pieces,
           although you can still do it by hand using Edit Position.  Some
           variants are supported only in ICS mode, including bughouse, and
           kriegspiel.  The winning/drawing conditions in crazyhouse (off-
           board interposition on mate) are not fully understood, but
           losers, suicide, giveaway, atomic, and 3check should be OK.
           Berolina and cylinder chess can only be played with legality
           testing off.  In crazyhouse, XBoard now does keep track of off-
           board pieces.  In shatranj it does implement the baring rule when
           mate detection is switched on.

      -boardHeight N
           Allows you to set a non-standard number of board ranks in any
           variant. If the height is given as -1, the default height for the
           variant is used.  Default: -1



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      -boardWidth N
           Allows you to set a non-standard number of board files in any
           variant. If the width is given as -1, the default width for the
           variant is used. With a non-standard width, the initial position
           will always be an empty board, as the usual opening array will
           not fit.  Default: -1

      -holdingsSize N
           Allows you to set a non-standard size for the holdings in any
           variant. If the size is given as -1, the default holdings size
           for the variant is used. The first N piece types will go into the
           holdings on capture, and you will be able to drop them on the
           board in stead of making a normal move. If size equals 0, there
           will be no holdings.  Default: -1

      -defaultFrcPosition N
           Specifies the number of the opening position in shuffle games
           like Chess960. A value of -1 means the position is randomly
           generated by XBoard at the beginning of every game.  Default: -1

      -pieceToCharTable string
           The characters that are used to represent the piece types XBoard
           knows in FEN diagrams and SAN moves. The string argument has to
           have an even length (or it will be ignored), as white and black
           pieces have to be given separately (in that order). The last
           letter for each color will be the King. The letters before that
           will be PNBRQ and then a whole host of fairy pieces in an order
           that has not fully crystallized yet (currently FEACWMOHIJGDVSLU,
           F=Ferz, Elephant, A=Archbishop, C=Chancellor, W=Wazir,
           M=Commoner, O=Cannon, H=Nightrider). You should list at least all
           pieces that occur in the variant you are playing. If you have
           less than 44 characters in the string, the pieces not mentioned
           will get assigned a period, and you will not be able to
           distinguish them in FENs. You can also explicitly assign pieces a
           period, in which case they will not be counted in deciding which
           captured pieces can go into the holdings.  A tilde '~' as a piece
           name does mean this piece is used to represent a promoted Pawn in
           crazyhouse-like games, i.e. on capture it turns back onto a Pawn.
           A '+' similarly indicates the piece is a shogi-style promoted
           piece, that should revert to its non-promoted version on capture
           (rather than to a Pawn).  Note that promoted pieces are
           represented by pieces 11 further in the list.  You should not
           have to use this option often: each variant has its own default
           setting for the piece representation in FEN, which should be
           sufficient in normal use.  Default: ""

      -pieceNickNames string
           The characters in the string are interpreted the same way as in
           the `pieceToCharTable' option. But on input, piece-ID letters are
           first looked up in the nicknames, and only if not defined there,
           in the normal pieceToCharTable. This allows you to have two



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           letters designate the same piece, (e.g. N as an alternative to H
           for Horse in Xiangqi), to make reading of non-compliant notations
           easier.  Default: ""

      -colorNickNames string
           The side-to-move field in a FEN will be first matched against the
           letters in the string (first character for white, second for
           black), before it is matched to the regular 'w' and 'b'.  This
           makes it easier to read non-compliant FENs, which, say, use 'r'
           for white.  Default: ""

      -debug/-xdebug or -debugMode true/false
           Turns on debugging printout.

      -debugFile filename or -nameOfDebugFile filename
           Sets the name of the file to which XBoard saves debug information
           (including all communication to and from the engines).  A `%d' in
           the given file name (e.g. game%d.debug) will be replaced by the
           unique sequence number of a tournament game, so that the debug
           output of each game will be written on a separate file.

      -engineDebugOutput number
           Specifies how XBoard should handle unsolicited output from the
           engine, with respect to saving it in the debug file. The output
           is further (hopefully) ignored. If number=0, XBoard refrains from
           writing such spurious output to the debug file. If number=1, all
           engine output is written faithfully to the debug file. If
           number=2, any protocol-violating line is prefixed with a '#'
           character, as the engine itself should have done if it wanted to
           submit info for inclusion in the debug file.  This option is
           provided for the benefit of applications that use the debug file
           as a source of information, such as the broadcaster of live games
           TLCV / TLCS. Such applications can be protected from spurious
           engine output that might otherwise confuse them.

      -rsh or -remoteShell shell-name
           Name of the command used to run programs remotely. The default is
           `rsh' or `remsh', determined when XBoard is configured and
           compiled.

      -ruser or -remoteUser user-name
           User name on the remote system when running programs with the
           `remoteShell'. The default is your local user name.

      -userName username
           Name under which the Human player will be listed in the PGN file.
           Default is the login name on your local computer.

      -delayBeforeQuit number
      -delayAfterQuit number
           These options specify how long XBoard has to wait before sending



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           a termination signal to rogue engine processes, that do not want
           to react to the 'quit' command. The second one determines the
           pause after killing the engine, to make sure it dies.

      -searchMode n
           The integer n encodes the mode for the `find position' function.
           Default: 1 (= Exact position match)

      -eloThresholdBoth elo
      -eloThresholdAny elo
           Defines a lower limit for the Elo rating, which has to be
           surpassed before a game will be considered when searching for a
           board position.  Default: 0

      -dateThreshold year
           Only games not played before the given year will be considered
           when searching for a board position


 CHESS SERVERS
      An "Internet Chess Server", or "ICS", is a place on the Internet where
      people can get together to play chess, watch other people's games, or
      just chat.  You can use either `telnet' or a client program like
      XBoard to connect to the server.  There are thousands of registered
      users on the different ICS hosts, and it is not unusual to meet 200 on
      both chessclub.com and freechess.org.

      Most people can just type `xboard -ics' to start XBoard as an ICS
      client.  Invoking XBoard in this way connects you to the Internet
      Chess Club (ICC), a commercial ICS.  You can log in there as a guest
      even if you do not have a paid account.  To connect to the largest
      Free ICS (FICS), use the command `xboard -ics -icshost freechess.org'
      instead, or substitute a different host name to connect to your
      favorite ICS.  For a full description of command-line options that
      control the connection to ICS and change the default values of ICS
      options, see ICS options.

      While you are running XBoard as an ICS client, you use the terminal
      window that you started XBoard from as a place to type in commands and
      read information that is not available on the chessboard.

      The first time you need to use the terminal is to enter your login
      name and password, if you are a registered player. (You don't need to
      do this manually; the `icsLogon' option can do it for you.  See ICS
      options.)  If you are not registered, enter `g' as your name, and the
      server will pick a unique guest name for you.

      Some useful ICS commands include

      help <topic>
           to get help on the given <topic>. To get a list of possible



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           topics type "help" without topic.  Try the help command before
           you ask other people on the server for help.

           For example `help register' tells you how to become a registered
           ICS player.

      who <flags>
           to see a list of people who are logged on.  Administrators
           (people you should talk to if you have a problem) are marked with
           the character `*', an asterisk. The <flags> allow you to display
           only selected players: For example, `who of' shows a list of
           players who are interested in playing but do not have an
           opponent.

      games
           to see what games are being played

      match <player> [<mins>] [<inc>]
           to challenge another player to a game. Both opponents get <mins>
           minutes for the game, and <inc> seconds will be added after each
           move.  If another player challenges you, the server asks if you
           want to accept the challenge; use the `accept' or `decline'
           commands to answer.

      accept
      decline
           to accept or decline another player's offer. The offer may be to
           start a new game, or to agree to a `draw', `adjourn' or `abort'
           the current game. See Action Menu.

           If you have more than one pending offer (for example, if more
           than one player is challenging you, or if your opponent offers
           both a draw and to adjourn the game), you have to supply
           additional information, by typing something like `accept
           <player>', `accept draw', or `draw'.

      draw
      adjourn
      abort
           asks your opponent to terminate a game by mutual agreement.
           Adjourned games can be continued later. Your opponent can either
           `decline' your offer or accept it (by typing the same command or
           typing `accept').  In some cases these commands work immediately,
           without asking your opponent to agree.  For example, you can
           abort the game unilaterally if your opponent is out of time, and
           you can claim a draw by repetition or the 50-move rule if
           available simply by typing `draw'.

      finger <player>
           to get information about the given <player>. (Default: yourself.)




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      vars to get a list of personal settings

      set <var> <value>
           to modify these settings

      observe <player>
           to observe an ongoing game of the given <player>.

      examine
      oldmoves
           to review a recently completed game

      Some special XBoard features are activated when you are in examine
      mode on ICS.  See the descriptions of the menu commands `Forward',
      `Backward', `Pause', `ICS Client', and `Stop Examining' on the Edit
      Menu, Mode Menu, and Action Menu.


 FIREWALLS
      By default, XBoard communicates with an Internet Chess Server by
      opening a TCP socket directly from the machine it is running on to the
      ICS. If there is a firewall between your machine and the ICS, this
      won't work. Here are some recipes for getting around common kinds of
      firewalls using special options to XBoard.  Important: See the
      paragraph in the below about extra echoes, in Limitations.

      Suppose that you can't telnet directly to ICS, but you can telnet to a
      firewall host, log in, and then telnet from there to ICS.  Let's say
      the firewall is called `firewall.example.com'. Set command-line
      options as follows:

          xboard -ics -icshost firewall.example.com -icsport 23

      Then when you run XBoard in ICS mode, you will be prompted to log in
      to the firewall host. This works because port 23 is the standard
      telnet login service. Do so, then telnet to ICS, using a command like
      `telnet chessclub.com 5000', or whatever command the firewall provides
      for telnetting to port 5000.

      If your firewall lets you telnet (or rlogin) to remote hosts but
      doesn't let you telnet to port 5000, you may be able to connect to the
      chess server on port 23 instead, which is the port the telnet program
      uses by default.  Some chess servers support this (including
      chessclub.com and freechess.org), while some do not.

      If your chess server does not allow connections on port 23 and your
      firewall does not allow you to connect to other ports, you may be able
      to connect by hopping through another host outside the firewall that
      you have an account on.  For instance, suppose you have a shell
      account at `foo.edu'. Follow the recipe above, but instead of typing
      `telnet chessclub.com 5000' to the firewall, type `telnet foo.edu' (or



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      `rlogin foo.edu'), log in there, and then type `telnet chessclub.com
      5000'.

      Suppose that you can't telnet directly to ICS, but you can use rsh to
      run programs on a firewall host, and that host can telnet to ICS.
      Let's say the firewall is called `rsh.example.com'. Set command-line
      options as follows:

          xboard -ics -gateway rsh.example.com -icshost chessclub.com

      Then when you run XBoard in ICS mode, it will connect to the ICS by
      using `rsh' to run the command `telnet chessclub.com 5000' on host
      `rsh.example.com'.

      Suppose that you can telnet anywhere you want, but you have to run a
      special program called `ptelnet' to do so.

      First, we'll consider the easy case, in which `ptelnet chessclub.com
      5000' gets you to the chess server.  In this case set command line
      options as follows:

          xboard -ics -telnet -telnetProgram ptelnet

      Then when you run XBoard in ICS mode, it will issue the command
      `ptelnet chessclub.com 5000' to connect to the ICS.

      Next, suppose that `ptelnet chessclub.com 5000' doesn't work; that is,
      your `ptelnet' program doesn't let you connect to alternative ports.
      As noted above, your chess server may allow you to connect on port 23
      instead.  In that case, just add the option `-icsport ""' to the above
      command.  But if your chess server doesn't let you connect on port 23,
      you will have to find some other host outside the firewall and hop
      through it. For instance, suppose you have a shell account at
      `foo.edu'. Set command line options as follows:

          xboard -ics -telnet -telnetProgram ptelnet -icshost foo.edu -icsport ""

      Then when you run XBoard in ICS mode, it will issue the command
      `ptelnet foo.edu' to connect to your account at `foo.edu'. Log in
      there, then type `telnet chessclub.com 5000'.

      ICC timestamp and FICS timeseal do not work through some firewalls.
      You can use them only if your firewall gives a clean TCP connection
      with a full 8-bit wide path.  If your firewall allows you to get out
      only by running a special telnet program, you can't use timestamp or
      timeseal across it.  But if you have access to a computer just outside
      your firewall, and you have much lower netlag when talking to that
      computer than to the ICS, it might be worthwhile running timestamp
      there.  Follow the instructions above for hopping through a host
      outside the firewall (foo.edu in the example), but run timestamp or
      timeseal on that host instead of telnet.



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      Suppose that you have a SOCKS firewall that will give you a clean 8-
      bit wide TCP connection to the chess server, but only after you
      authenticate yourself via the SOCKS protocol.  In that case, you could
      make a socksified version of XBoard and run that.  If you are using
      timestamp or timeseal, you will to socksify it, not XBoard; this may
      be difficult seeing that ICC and FICS do not provide source code for
      these programs.  Socksification is beyond the scope of this document,
      but see the SOCKS Web site at http://www.socks.permeo.com/.  If you
      are missing SOCKS, try http://www.funbureau.com/.


 ENVIRONMENT VARIABLES
      Game and position files are found in a directory named by the
      `CHESSDIR' environment variable. If this variable is not set, the
      current working directory is used. If `CHESSDIR' is set, XBoard
      actually changes its working directory to `$CHESSDIR', so any files
      written by the chess engine will be placed there too.


 LIMITATIONS AND KNOWN BUGS
      There is no way for two people running copies of XBoard to play each
      other without going through an Internet Chess Server.

      Under some circumstances, your ICS password may be echoed when you log
      on.

      If you are connecting to the ICS by running telnet on an Internet
      provider or firewall host, you may find that each line you type is
      echoed back an extra time after you hit <Enter>. If your Internet
      provider is a Unix system, you can probably turn its echo off by
      typing `stty -echo' after you log in, and/or typing <^E><Enter>
      (Ctrl+E followed by the Enter key) to the telnet program after you
      have logged into ICS.  It is a good idea to do this if you can,
      because the extra echo can occasionally confuse XBoard's parsing
      routines.

      The game parser recognizes only algebraic notation.

      Many of the following points used to be limitations in XBoard 4.2.7
      and earlier, but are now fixed: The internal move legality tester in
      XBoard 4.3.xx does look at the game history, and is fully aware of
      castling or en-passant-capture rights. It permits castling with the
      king on the d file because this is possible in some "wild 1" games on
      ICS. The piece-drop menu does not check piece drops in bughouse to see
      if you actually hold the piece you are trying to drop. But this way of
      dropping pieces should be considered an obsolete feature, now that
      pieces can be dropped by dragging them from the holdings to the board.
      Anyway, if you would attempt an illegal move when using a chess engine
      or the ICS, XBoard will accept the error message that comes back, undo
      the move, and let you try another.  FEN positions saved by XBoard do
      include correct information about whether castling or en passant are



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      legal, and also handle the 50-move counter.  The mate detector does
      not understand that non-contact mate is not really mate in bughouse.
      The only problem this causes while playing is minor: a "#" (mate
      indicator) character will show up after a non-contact mating move in
      the move list. XBoard will not assume the game is over at that point,
      not even when the option Detect Mates is on.  Edit Game mode always
      uses the rules of the selected variant, which can be a variant that
      uses piece drops. You can load and edit games that contain piece
      drops. The (obsolete) piece menus are not active, but you can perform
      piece drops by dragging pieces from the holdings.  Fischer Random
      castling is fully understood. You can enter castlings by dragging the
      King on top of your Rook. You can probably also play Fischer Random
      successfully on ICS by typing castling moves into the ICS Interaction
      window.

      The menus may not work if your keyboard is in Caps Lock or Num Lock
      mode.  This seems to be a problem with the Athena menu widget, not an
      XBoard bug.

      Also see the ToDo file included with the distribution for many other
      possible bugs, limitations, and ideas for improvement that have been
      suggested.

 REPORTING PROBLEMS
      You can report bugs and problems with XBoard using the bug tracker at
      `https://savannah.gnu.org/projects/xboard/' or by sending mail to
      `<bug-xboard@gnu.org>'.  It can also be useful to report or discuss
      bugs in the WinBoard Forum at `http://www.open-aurec.com/wbforum/',
      WinBoard development section.

      Please use the `script' program to start a typescript, run XBoard with
      the `-debug' option, and include the typescript output in your
      message.  Also tell us what kind of machine and what operating system
      version you are using.  The command `uname -a' will often tell you
      this.

      If you improve XBoard, please send a message about your changes, and
      we will get in touch with you about merging them in to the main line
      of development.


 AUTHORS AND CONTRIBUTORS
      Chris Sears and Dan Sears wrote the original XBoard.  They were
      responsible for versions 1.0 through 1.2.  The color scheme was taken
      from Wayne Christopher's `XChess' program.

      Tim Mann was primarily responsible for XBoard versions 1.3 through
      4.2.7, and for WinBoard (a port of XBoard to Microsoft Win32) from its
      inception through version 4.2.7.

      John Chanak contributed the initial implementation of ICS mode.  Evan



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      Welsh wrote `CMail', and Patrick Surry helped in designing, testing,
      and documenting it.  Elmar Bartel contributed the new piece bitmaps
      introduced in version 3.2.  Jochen Wiedmann converted the
      documentation to texinfo.  Frank McIngvale added click/click moving,
      the Analysis modes, piece flashing, ZIICS import, and ICS text
      colorization to XBoard.  Hugh Fisher added animated piece movement to
      XBoard, and Henrik Gram added it to WinBoard.  Mark Williams
      contributed the initial (WinBoard-only) implementation of many new
      features added to both XBoard and WinBoard in version 4.1.0, including
      copy/paste, premove, icsAlarm, autoFlipView, training mode, auto
      raise, and blindfold.  Ben Nye contributed X copy/paste code for
      XBoard.

      In a fork from version 4.2.7, Alessandro Scotti added many elements to
      the user interface of WinBoard, including the board textures and
      font-based rendering, the evaluation-graph, move-history and engine-
      output window.  He was also responsible for adding the UCI support.

      H. G. Muller continued this fork of the project, producing version
      4.3.  He made WinBoard castling- and e.p.-aware, added variant support
      with adjustable board sizes, the crazyhouse holdings, and the fairy
      pieces.  In addition he added most of the adjudication options, made
      WinBoard more robust in dealing with buggy and crashing engines, and
      extended time control with a time-odds and node-count-based modes.
      Most of the options that initially were WinBoard only have now been
      back-ported to XBoard.

      Michel van den Bergh provided the code for reading Polyglot opening
      books.

      Meanwhile, some work continued on the GNU XBoard project maintained at
      savannah.gnu.org, but version 4.2.8 was never released.  Daniel
      Mehrmann was responsible for much of this work.

      Most recently, Arun Persaud worked with H. G. Muller to merge all the
      features of the never-released XBoard/WinBoard 4.2.8 of the GNU XBoard
      project and the never-released 4.3.16 from H. G.'s fork into a unified
      XBoard/WinBoard 4.4, which is now available both from the
      savannah.gnu.org web site and the WinBoard forum.


 CMAIL
      The `cmail' program can help you play chess by email with opponents of
      your choice using XBoard as an interface.

      You will usually run `cmail' without giving any options.


    CMail options
      -h   Displays `cmail' usage information.




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      -c   Shows the conditions of the GNU General Public License.  See
           Copying.

      -w   Shows the warranty notice of the GNU General Public License.  See
           Copying.

      -v
      -xv  Provides or inhibits verbose output from `cmail' and XBoard,
           useful for debugging. The `-xv' form also inhibits the cmail
           introduction message.

      -mail
      -xmail
           Invokes or inhibits the sending of a mail message containing the
           move.

      -xboard
      -xxboard
           Invokes or inhibits the running of XBoard on the game file.

      -reuse
      -xreuse
           Invokes or inhibits the reuse of an existing XBoard to display
           the current game.

      -remail
           Resends the last mail message for that game. This inhibits
           running XBoard.

      -game <name>
           The name of the game to be processed.

      -wgames <number>
      -bgames <number>
      -games <number>
           Number of games to start as White, as Black or in total. Default
           is 1 as white and none as black. If only one color is specified
           then none of the other color is assumed. If no color is specified
           then equal numbers of White and Black games are started, with the
           extra game being as White if an odd number of total games is
           specified.

      -me <short name>
      -opp <short name>
           A one-word alias for yourself or your opponent.

      -wname <full name>
      -bname <full name>
      -myname <full name>
      -oppname <full name>
           The full name of White, Black, yourself or your opponent.



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      -wna <net address>
      -bna <net address>
      -na <net address>
      -oppna <net address>
           The email address of White, Black, yourself or your opponent.

      -dir <directory>
           The directory in which `cmail' keeps its files. This defaults to
           the environment variable `$CMAIL_DIR' or failing that,
           `$CHESSDIR', `$HOME/Chess' or `~/Chess'. It will be created if it
           does not exist.

      -arcdir <directory>
           The directory in which `cmail' archives completed games. Defaults
           to the environment variable `$CMAIL_ARCDIR' or, in its absence,
           the same directory as cmail keeps its working files (above).

      -mailprog <mail program>
           The program used by cmail to send email messages. This defaults
           to the environment variable `$CMAIL_MAILPROG' or failing that
           `/usr/ucb/Mail', `/usr/ucb/mail' or `Mail'. You will need to set
           this variable if none of the above paths fit your system.

      -logFile <file>
           A file in which to dump verbose debugging messages that are
           invoked with the `-v' option.

      -event <event>
           The PGN Event tag (default `Email correspondence game').

      -site <site>
           The PGN Site tag (default `NET').

      -round <round>
           The PGN Round tag (default `-', not applicable).

      -mode <mode>
           The PGN Mode tag (default `EM', Electronic Mail).

      Other options
           Any option flags not listed above are passed through to XBoard.
           Invoking XBoard through CMail changes the default values of two
           XBoard options: The default value for `-noChessProgram' is
           changed to true; that is, by default no chess engine is started.
           The default value for `-timeDelay' is changed to 0; that is, by
           default XBoard immediately goes to the end of the game as played
           so far, rather than stepping through the moves one by one.  You
           can still set these options to whatever values you prefer by
           supplying them on CMail's command line.  See Options.





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                                   $Date:



    Starting a CMail Game
      Type `cmail' from a shell to start a game as white. After an opening
      message, you will be prompted for a game name, which is optional -- if
      you simply press <Enter>, the game name will take the form `you-VS-
      opponent'. You will next be prompted for the short name of your
      opponent. If you haven't played this person before, you will also be
      prompted for his/her email address. `cmail' will then invoke XBoard in
      the background. Make your first move and select `Mail Move' from the
      `File' menu. See File Menu. If all is well, `cmail' will mail a copy
      of the move to your opponent. If you select `Exit' without having
      selected `Mail Move' then no move will be made.


    Answering a Move
      When you receive a message from an opponent containing a move in one
      of your games, simply pipe the message through `cmail'. In some
      mailers this is as simple as typing `| cmail' when viewing the
      message, while in others you may have to save the message to a file
      and do `cmail < file' at the command line. In either case `cmail' will
      display the game using XBoard. If you didn't exit XBoard when you made
      your first move then `cmail' will do its best to use the existing
      XBoard instead of starting a new one. As before, simply make a move
      and select `Mail Move' from the `File' menu. See File Menu. `cmail'
      will try to use the XBoard that was most recently used to display the
      current game. This means that many games can be in progress
      simultaneously, each with its own active XBoard.

      If you want to look at the history or explore a variation, go ahead,
      but you must return to the current position before XBoard will allow
      you to mail a move. If you edit the game's history you must select
      `Reload Same Game' from the `File' menu to get back to the original
      position, then make the move you want and select `Mail Move'.  As
      before, if you decide you aren't ready to make a move just yet you can
      either select `Exit' without sending a move or just leave XBoard
      running until you are ready.


    Multi-Game Messages
      It is possible to have a `cmail' message carry more than one game.
      This feature was implemented to handle IECG (International Email Chess
      Group) matches, where a match consists of one game as white and one as
      black, with moves transmitted simultaneously. In case there are more
      general uses, `cmail' itself places no limit on the number of
      black/white games contained in a message; however, XBoard does.


    Completing a Game
      Because XBoard can detect checkmate and stalemate, `cmail' handles
      game termination sensibly. As well as resignation, the `Action' menu
      allows draws to be offered and accepted for `cmail' games.




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                                   $Date:



      For multi-game messages, only unfinished and just-finished games will
      be included in email messages. When all the games are finished, they
      are archived in the user's archive directory, and similarly in the
      opponent's when he or she pipes the final message through `cmail'. The
      archive file name includes the date the game was started.


    Known CMail Problems
      It's possible that a strange conjunction of conditions may
      occasionally mean that `cmail' has trouble reactivating an existing
      XBoard. If this should happen, simply trying it again should work.  If
      not, remove the file that stores the XBoard's PID (`game.pid') or use
      the `-xreuse' option to force `cmail' to start a new XBoard.

      Versions of `cmail' after 2.16 no longer understand the old file
      format that XBoard used to use and so cannot be used to correspond
      with anyone using an older version.

      Versions of `cmail' older than 2.11 do not handle multi-game messages,
      so multi-game correspondence is not possible with opponents using an
      older version.


 OTHER PROGRAMS YOU CAN USE WITH
      Here are some other programs you can use with XBoard


    GNU Chess
      The GNU Chess engine is available from:

      ftp://ftp.gnu.org/gnu/gnuchess/

      You can use XBoard to play a game against GNU Chess, or to interface
      GNU Chess to an ICS.


    Fairy-Max
      Fairy-Max is a derivative from the once World's smallest Chess program
      micro-Max, which measures only about 100 lines of source code.  The
      main difference with micro-Max is that Fairy-Max loads its move-
      generator tables from a file, so that the rules for piece movement can
      be easily configured to implement unorthodox pieces.  Fairy-Max can
      therefore play a large number of variants, normal Chess being one of
      those.  In addition it plays Knightmate, Capablanca and Gothic Chess,
      Shatranj, Courier Chess, Cylinder chess, Berolina Chess, while the
      user can easily define new variants.  It can be obtained from:

      http://home.hccnet.nl/h.g.muller/dwnldpage.html






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                                   $Date:



    HoiChess
      HoiChess is a not-so-very-strong Chess engine, which comes with a
      derivative HoiXiangqi, able to play Chinese Chess. It can be obtained
      from the standard Linux repositories through:

      sudo apt-get install hoichess


    Crafty
      Crafty is a chess engine written by Bob Hyatt.  You can use XBoard to
      play a game against Crafty, hook Crafty up to an ICS, or use Crafty to
      interactively analyze games and positions for you.

      Crafty is a strong, rapidly evolving chess program. This rapid pace of
      development is good, because it means Crafty is always getting better.
      This can sometimes cause problems with backwards compatibility, but
      usually the latest version of Crafty will work well with the latest
      version of XBoard.  Crafty can be obtained from its author's FTP site:
      ftp://ftp.cis.uab.edu/hyatt/.

      To use Crafty with XBoard, give the -fcp and -fd options as follows,
      where <crafty's directory> is the directory in which you installed
      Crafty and placed its book and other support files.


    zic2xpm
      The ``zic2xpm'' program is used to import chess sets from the ZIICS(*)
      program into XBoard. ``zic2xpm'' is part of the XBoard distribution.
      ZIICS is available from:

      ftp://ftp.freechess.org/pub/chess/DOS/ziics131.exe

      To import ZIICS pieces, do this:

      1. Unzip ziics131.exe into a directory:

               unzip -L ziics131.exe -d ~/ziics

      2. Use zic2xpm to convert a

           For example, let's say you want to use the FRITZ4 set. These
           files are named ``fritz4.*'' in the ZIICS distribution.

               mkdir ~/fritz4
               cd ~/fritz4
               zic2xpm ~/ziics/fritz4.*

      3. Give XBoard the ``-pixmap'' option

               xboard -pixmap ~/fritz4




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                                   $Date:



      (*) ZIICS is a separate copyrighted work of Andy McFarland.  The
      ``ZIICS pieces'' are copyrighted works of their respective creators.
      Files produced by ``zic2xpm'' are for PERSONAL USE ONLY and may NOT be
      redistributed without explicit permission from the original creator(s)
      of the pieces.


 COPYRIGHT
      Copyright (C) 1991 Digital Equipment Corporation, Maynard,
      Massachusetts.

      All Rights Reserved.

      Permission to use, copy, modify, and distribute this software and its
      documentation for any purpose and without fee is hereby granted,
      provided that the above copyright notice appear in all copies and that
      both that copyright notice and this permission notice appear in
      supporting documentation, and that the name of Digital not be used in
      advertising or publicity pertaining to distribution of the software
      without specific, written prior permission.

      Digital disclaims all warranties with regard to this software,
      including all implied warranties of merchantability and fitness.  In
      no event shall Digital be liable for any special, indirect or
      consequential damages or any damages whatsoever resulting from loss of
      use, data or profits, whether in an action of contract, negligence or
      other tortious action, arising out of or in connection with the use or
      performance of this software.

      Enhancements copyright (C) 1992-2003, 2004, 2005, 2006, 2007, 2008,
      2009, 2010, 2011, 2012, 2013, 2014 Free Software Foundation, Inc.

      Published by the Free Software Foundation
      59 Temple Place - Suite 330
      Boston, MA 02111-1307 USA

      Permission is granted to make and distribute verbatim copies of this
      manual provided the copyright notice and this permission notice are
      preserved on all copies.

      Permission is granted to copy and distribute modified versions of this
      manual under the conditions for verbatim copying, provided also that
      the section entitled ``GNU General Public License,'' is included
      exactly as in the original, and provided that the entire resulting
      derived work is distributed under the terms of a permission notice
      identical to this one.

      Permission is granted to copy and distribute translations of this
      manual into another language, under the above conditions for modified
      versions, except that the section entitled ``GNU General Public
      License,'' and this permission notice, may be included in translations



                                   - 74 -      Formatted:  December 21, 2024






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                                   $Date:



      approved by the Free Software Foundation instead of in the original
      English.


 GNU GENERAL PUBLIC LICENSE
      Copyright (C) 2007 Free Software Foundation, Inc. `http://fsf.org/'

      Everyone is permitted to copy and distribute verbatim copies of this
      license document, but changing it is not allowed.

      The GNU General Public License is a free, copyleft license for
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      The licenses for most software and other practical works are designed
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      To protect your rights, we need to prevent others from denying you
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      Developers that use the GNU GPL protect your rights with two steps:
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      authors' sake, the GPL requires that modified versions be marked as
      changed, so that their problems will not be attributed erroneously to
      authors of previous versions.




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      Some devices are designed to deny users access to install or run
      modified versions of the software inside them, although the
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      Finally, every program is threatened constantly by software patents.
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      assures that patents cannot be used to render the program non-free.

      The precise terms and conditions for copying, distribution and
      modification follow.


      Definitions.
           ``This License'' refers to version 3 of the GNU General Public
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           ``Copyright'' also means copyright-like laws that apply to other
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           making available to the public, and in some countries other
           activities as well.



                                   - 76 -      Formatted:  December 21, 2024






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                                   $Date:



           To ``convey'' a work means any kind of propagation that enables
           other parties to make or receive copies.  Mere interaction with a
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           An interactive user interface displays ``Appropriate Legal
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           data communication or control flow between those subprograms and



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                                   $Date:



           other parts of the work.

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                                   - 78 -      Formatted:  December 21, 2024






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                                   $Date:



      Conveying Verbatim Copies.
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                                   - 79 -      Formatted:  December 21, 2024






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                                   $Date:



           of the aggregate.


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           excluded from the Corresponding Source as a System Library, need
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           or key for unpacking, reading or copying.


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           If you add terms to a covered work in accord with this section,
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           Additional terms, permissive or non-permissive, may be stated in
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      Termination.
           You may not propagate or modify a covered work except as
           expressly provided under this License.  Any attempt otherwise to
           propagate or modify it is void, and will automatically terminate
           your rights under this License (including any patent licenses
           granted under the third paragraph of section 11).

           However, if you cease all violation of this License, then your
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           Moreover, your license from a particular copyright holder is
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           Termination of your rights under this section does not terminate
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      Acceptance Not Required for Having Copies.
           You are not required to accept this License in order to receive
           or run a copy of the Program.  Ancillary propagation of a covered



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           work occurring solely as a consequence of using peer-to-peer
           transmission to receive a copy likewise does not require
           acceptance.  However, nothing other than this License grants you
           permission to propagate or modify any covered work.  These
           actions infringe copyright if you do not accept this License.
           Therefore, by modifying or propagating a covered work, you
           indicate your acceptance of this License to do so.


      Automatic Licensing of Downstream Recipients.
           Each time you convey a covered work, the recipient automatically
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           An ``entity transaction'' is a transaction transferring control
           of an organization, or substantially all assets of one, or
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           propagation of a covered work results from an entity transaction,
           each party to that transaction who receives a copy of the work
           also receives whatever licenses to the work the party's
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           You may not impose any further restrictions on the exercise of
           the rights granted or affirmed under this License.  For example,
           you may not impose a license fee, royalty, or other charge for
           exercise of rights granted under this License, and you may not
           initiate litigation (including a cross-claim or counterclaim in a
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           using, selling, offering for sale, or importing the Program or
           any portion of it.


      Patents.
           A ``contributor'' is a copyright holder who authorizes use under
           this License of the Program or a work on which the Program is
           based.  The work thus licensed is called the contributor's
           ``contributor version''.

           A contributor's ``essential patent claims'' are all patent claims
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           or hereafter acquired, that would be infringed by some manner,
           permitted by this License, of making, using, or selling its
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           infringed only as a consequence of further modification of the
           contributor version.  For purposes of this definition,
           ``control'' includes the right to grant patent sublicenses in a



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           manner consistent with the requirements of this License.

           Each contributor grants you a non-exclusive, worldwide, royalty-
           free patent license under the contributor's essential patent
           claims, to make, use, sell, offer for sale, import and otherwise
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           In the following three paragraphs, a ``patent license'' is any
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           party.

           If you convey a covered work, knowingly relying on a patent
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           the Corresponding Source to be so available, or (2) arrange to
           deprive yourself of the benefit of the patent license for this
           particular work, or (3) arrange, in a manner consistent with the
           requirements of this License, to extend the patent license to
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           actual knowledge that, but for the patent license, your conveying
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           covered work in a country, would infringe one or more
           identifiable patents in that country that you have reason to
           believe are valid.

           If, pursuant to or in connection with a single transaction or
           arrangement, you convey, or propagate by procuring conveyance of,
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           receiving the covered work authorizing them to use, propagate,
           modify or convey a specific copy of the covered work, then the
           patent license you grant is automatically extended to all
           recipients of the covered work and works based on it.

           A patent license is ``discriminatory'' if it does not include
           within the scope of its coverage, prohibits the exercise of, or
           is conditioned on the non-exercise of one or more of the rights
           that are specifically granted under this License.  You may not
           convey a covered work if you are a party to an arrangement with a
           third party that is in the business of distributing software,
           under which you make payment to the third party based on the
           extent of your activity of conveying the work, and under which
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           the covered work from you, a discriminatory patent license (a) in
           connection with copies of the covered work conveyed by you (or



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           copies made from those copies), or (b) primarily for and in
           connection with specific products or compilations that contain
           the covered work, unless you entered into that arrangement, or
           that patent license was granted, prior to 28 March 2007.

           Nothing in this License shall be construed as excluding or
           limiting any implied license or other defenses to infringement
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           law.


      No Surrender of Others' Freedom.
           If conditions are imposed on you (whether by court order,
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           to collect a royalty for further conveying from those to whom you
           convey the Program, the only way you could satisfy both those
           terms and this License would be to refrain entirely from
           conveying the Program.


      Use with the GNU Affero General
           Notwithstanding any other provision of this License, you have
           permission to link or combine any covered work with a work
           licensed under version 3 of the GNU Affero General Public License
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           The terms of this License will continue to apply to the part
           which is the covered work, but the special requirements of the
           GNU Affero General Public License, section 13, concerning
           interaction through a network will apply to the combination as
           such.


      Revised Versions of this License.
           The Free Software Foundation may publish revised and/or new
           versions of the GNU General Public License from time to time.
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           version, but may differ in detail to address new problems or
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           Each version is given a distinguishing version number.  If the
           Program specifies that a certain numbered version of the GNU
           General Public License ``or any later version'' applies to it,
           you have the option of following the terms and conditions either
           of that numbered version or of any later version published by the
           Free Software Foundation.  If the Program does not specify a
           version number of the GNU General Public License, you may choose



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           any version ever published by the Free Software Foundation.

           If the Program specifies that a proxy can decide which future
           versions of the GNU General Public License can be used, that
           proxy's public statement of acceptance of a version permanently
           authorizes you to choose that version for the Program.

           Later license versions may give you additional or different
           permissions.  However, no additional obligations are imposed on
           any author or copyright holder as a result of your choosing to
           follow a later version.


      Disclaimer of Warranty.
           THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
           APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE
           COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM ``AS
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      Limitation of Liability.
           IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
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           THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA
           BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
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      Interpretation of Sections 15 and 16.
           If the disclaimer of warranty and limitation of liability
           provided above cannot be given local legal effect according to
           their terms, reviewing courts shall apply local law that most
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           If you develop a new program, and you want it to be of the
           greatest possible use to the public, the best way to achieve this
           is to make it free software which everyone can redistribute and
           change under these terms.




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           To do so, attach the following notices to the program.  It is
           safest to attach them to the start of each source file to most
           effectively state the exclusion of warranty; and each file should
           have at least the ``copyright'' line and a pointer to where the
           full notice is found.

           ONE LINE TO GIVE THE PROGRAM'S NAME AND A BRIEF IDEA OF WHAT IT DOES.
           Copyright (C) YEAR NAME OF AUTHOR

           This program is free software: you can redistribute it and/or modify
           it under the terms of the GNU General Public License as published by
           the Free Software Foundation, either version 3 of the License, or (at
           your option) any later version.

           This program is distributed in the hope that it will be useful, but
           WITHOUT ANY WARRANTY; without even the implied warranty of
           MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
           General Public License for more details.

           You should have received a copy of the GNU General Public License
           along with this program.  If not, see `http://www.gnu.org/licenses/'.

           Also add information on how to contact you by electronic and
           paper mail.

           If the program does terminal interaction, make it output a short
           notice like this when it starts in an interactive mode:

           PROGRAM Copyright (C) YEAR NAME OF AUTHOR
           This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
           This is free software, and you are welcome to redistribute it
           under certain conditions; type `show c' for details.

           The hypothetical commands `show w' and `show c' should show the
           appropriate parts of the General Public License.  Of course, your
           program's commands might be different; for a GUI interface, you
           would use an ``about box''.

           You should also get your employer (if you work as a programmer)
           or school, if any, to sign a ``copyright disclaimer'' for the
           program, if necessary.  For more information on this, and how to
           apply and follow the GNU GPL, see `http://www.gnu.org/licenses/'.

           The GNU General Public License does not permit incorporating your
           program into proprietary programs.  If your program is a
           subroutine library, you may consider it more useful to permit
           linking proprietary applications with the library.  If this is
           what you want to do, use the GNU Lesser General Public License
           instead of this License.  But first, please read
           `http://www.gnu.org/philosophy/why-not-lgpl.html'.




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