xenial (6) xboard.6.gz

Provided by: xboard_4.8.0-2_amd64 bug

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 4.8.0 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.

       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  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.

   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 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.

       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 Selected Games
              Will cause all games selected for display in the current Game List to be appended to a file of the
              user's choice.

       Save Games as Book
              Creates  an  opening  book  from  the  currently  loaded  game  file, incorporating only the games
              currently selected in the Game List.  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 not  be  cleared,  so  that  you  can
              continue adding games from other game files.

       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'.

              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"]
                  [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.

       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.

       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 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
       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 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.

       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 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.

       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.

       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.

   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 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.

       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 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 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.

       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 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.

              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.

       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.  XBoard’s 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.  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:

       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 function 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,  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).

       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.

       In  the  Xaw  build  of  XBoard  you  can  add  or  remove  shortcut   keys   using   the   X   resources
       `paneA.translations'.  Here is an example of what could go into your `.Xdefaults' file:

           XBoard*paneA.translations: \
             Shift<Key>?: MenuItem(Help.About) \n\
             Ctrl<Key>y: MenuItem(Action.Accept) \n\
             Ctrl<Key>n: MenuItem(Action.Decline) \n\
             Ctrl<Key>i: MenuItem(Nothing)

       So the key should always be bound to the action 'MenuItem', with the (hierarchical) name of the menu item
       as argument.  There are a few actions available for which no menu item exists: Binding a key to `Nothing'
       makes  it  do nothing, thus removing it as a shortcut key. Other such functions that can be bound to keys
       are:

           AboutGame, DebugProc (switches the -debug option on or off),
           LoadNextGame, LoadPrevGame, ReloadGame, ReloadPosition.

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.

   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 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 `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.)

       -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 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).

       -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 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 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 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 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 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.

                  #!/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 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.

       -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,  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).

       -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.

       -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 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.  Usually 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
       -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.

       -autoInstall list
              When the list is set to a non-empty  string,  XBoard  will  scan  the  operating  system's  plugin
              directory for engines supporting UCI and XBoard protocol at startup.  When it finds an engine that
              was installed after it last saved its settings, a line to launch that engine (as per specs in  the
              plugin  file) is appended to the -firstChessProgramNames list of installed engines.  In the future
              it will be possible to use the list to limit this automatic adding of engines to a  certain  types
              of variants.

       -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.

       -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.  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
       -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 Xaw:
              -*-helvetica-bold-r-normal--*-*-*-*-*-*-*-*.  Default GTK: Sans Bold %d.

       -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 Xaw:  -*-helvetica-bold-r-normal--*-*-*-*-*-*-*-*.   Default  GTK:
              Sans Bold %d.

       -messageFont font
              The  font  used  for  popup  dialogs,  menus, 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  Xaw: -*-helvetica-medium-r-normal--*-*-*-*-*-*-*-*.  Default GTK: Sans Bold %d.  The font
              used in the Edit Tags dialog.  If the option value contains %d,  XBoard  will  replace  it  by  an
              appropriate  font  for the board size being used.  (Only used in GTK build.)  Default: Sans Normal
              %d.  The font used in the Edit Comment dialog.  If the  option  value  contains  %d,  XBoard  will
              replace  it  by  an  appropriate  font  for  the board size being used.  (Only used in GTK build.)
              Default: Sans Normal %d.  The font used to display ICS output in the ICS   Chat  window.   As  ICS
              output  often  contains  tables  aligned by spaces, a mono-space font is recommended here.  If the
              option value contains %d, XBoard will replace it by an appropriate font for the board  size  being
              used.  (Only used in GTK build.)  Default: Monospace Normal %d.  The font used in Move History and
              Engine Output windows.  As these windows display mainly moves, one could use a figurine font here.
              If  the option value contains %d, XBoard will replace it by an appropriate font for the board size
              being used.  (Only used in GTK build.)  Default: Sans Normal %d.  The font used in the listbox  of
              the  Game  List window.  If the option value contains %d, XBoard will replace it by an appropriate
              font for the board size being used.  (Only used in GTK build.)  Default: Sans Bold %d.

       -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
                  -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.
              If the filename ends in "-NxM.png", with integer N and M, it is assumed to contain a bitmap  of  a
              complete  board  of  N  files  and  M ranks, and XBoard will scale it to exactly match the current
              square size.  If N=M=0 it scales the entire bitmap to the size of the board, irrespective  of  the
              number of files and ranks of the latter.  Without any -NxM suffix textures are only blown up by an
              integer factor when they are smaller than the square size, or, when the name starts with "xq", too
              small to cover the complete Xiangqi board.  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  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.

       -memoHeaders true|false
              When true, column headers will be displayed in the Engine Output window for the depth, score, time
              and  nodes  data.  Right-clicking on these headers will hide or show the corresponding data.  (Not
              intended for dynamic use, as already printed data of the current search  will  not  be  affected!)
              Defaul: 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)

       -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
       -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)
                  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)
                  asean         ASEAN Chess (a modernized version of Makruk)
                  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

       -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 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 order pauses before and after sending the "quit" command to an engine that  must  be
              terminated.   The  pause  between quit and the previous command is specified in milliseconds.  The
              pause after quit is used to schedule a kill signal to be sent to  the  engine  process  after  the
              number  of  specified seconds plus one.  This signal is a different one as the terminiation signal
              described in the protocol specs which engines can suppress or ignore, and which is  sent  directly
              after  the  "quit"  command.   Setting  `delayAfterQuit'  to  -1 will suppress sending of the kill
              signal.  Default: 0

       -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 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.)

       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 `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.

       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 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 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.

       -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.

       -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.

   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.

       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 XBOARD

       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

   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.

       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
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       name of Digital not be used in advertising or  publicity  pertaining  to  distribution  of  the  software
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       Digital  disclaims  all  warranties  with  regard  to  this software, including all implied warranties of
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       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
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              The GNU General Public License  does  not  permit  incorporating  your  program  into  proprietary
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