bionic (6) xboard.6.gz

Provided by: xboard_4.9.1-1_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 4.9.1 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.
              To run engines that use the UCI  standard  XBoard  will  draw  upon  the  Polyglot  adapter  fully
              transparently, but you will need to have the polyglot package installed for this to work.

       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. To under-promote a Pawn you can drag it backwards
       until it morphs into the piece you want to promote to, after which you drag that forward to the promotion
       square.   Or after selecting the pawn with a first click you can then click the promotion square and move
       the mouse while keeping the button down until the piece that you want appears in  the  promotion  square.
       To  castle  you  move  the King to its destination or, in Chess960, on top of the Rook you want to castle
       with.  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 might 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 situations 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.
       Note that the board window can be sized by the user, but that this will not affect the size of the clocks
       above  it,  and won't be remembered in the settings file.  To persistently change the size of the clocks,
       use the `size' command-line option when starting XBoard.  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).

       shuffle
              Ticking `shuffle' will cause the current variant to be  played  with  shuffled  initial  position.
              Shuffling will preserve the possibility to castle in the way allowed by the variant.

       Fischer castling
              Ticking  `Fischer  castling'  will allow castling with Kings and Rooks that did not start in their
              normal place, as in Chess960.

       Start-position number
       randomize
       pick fixed
              The `Start-position number' selects a particular start position from all allowed shufflings, which
              will  then  be  used  for  every  new game.  Setting this to -1 (which can be done by pressing the
              `randomize' button) will cause a fresh random position to be picked for every new game.   Pressing
              the `pick fixed' button causes `Start-position number' to be set to a random value, to be used for
              all subsequent games.

       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  corresponding  choice  will  be  disabled.  XBoard supports all major
              variants, such as xiangqi, shogi, chess, chess960, makruk, Capablanca Chess, shatranj, crazyhouse,
              bughouse.

              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' for the chosen variant.

       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.  When you do this keeping the `Ctrl' key pressed,
              or start dragging with a double-click, you will move a copy of the piece, leaving the piece itself
              where  it  was.   In  variants  where pieces can promote (such as Shogi), left-clicking an already
              selected piece promotes or demotes 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.   (Note  you
              can  swap  the  function  of button 2 and 3 by pressing the shift key, and that there is an option
              `monoMouse' to combine al functions in one button, which then acts  as  button  3  over  an  empty
              square,  and  as  button 1 over a piece.)  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 already has the move (which is highlighted in
              black).  If you repeat this the board will cycle from empty to a `pallette board' containing every
              piece  once  to  the  initial  position  to the one before clearing.  The quickest way to set up a
              position is usually to start with the pallette board, and move the pieces to were you  want  them,
              duplicating them where necessary by using the `Ctrl' key, dragging those you don't want off board,
              and use static button 2 or 3 clicks to place the Pawns.  The old behavior with a  piece  menu  can
              still  be configured with the aid of the `pieceMenu' option.  Dragging empty squares off board can
              create boards with holes (inaccessible black squares) in them.  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 'save changes'.  When you press the button 'add next move',  and
              play a move on the board, that move will be added to the list with weight 1.  Note that the listed
              percentages are neither used, nor updated when you change the weights; they are just there  as  an
              optical aid.  When you right-click a move in the list it will be played.

       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  ???  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 might be added to the game, depending on the setting of the option 'Play moves of clicked PV',
              when  you  initiate  the  click left of the PV in the score area.  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: Clicking the words 'fewer' or 'more'
              will alter the number of variations shown at each depth,  through  the  engine's  MultiPV  option,
              while  clicking  in  between  those  and moving the mouse horizontally adjust the option 'Multi-PV
              Margin'. (In so far the engines support those.)

       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.  The title bar shows the score
              (and search depth at which it was obtained)  of  the  currently  displayed  position  numerically.
              Clicking  on  the  graph  will  bring the corresponding position in the board display.  A button 3
              click will toggle the display mode between plain and differential (showing the difference in score
              between  successive  half  moves).  Using the mouse wheel over the window will change the scale of
              the low-score region (from -1 to +1).

       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.  The line describing each game is built from a selection of the PGN
              tags.  Which tags contribute, and in what order, can be changed  by  the  `Game  list  tags'  menu
              dialog,  which  can  be  popped  up through the `Tags' button below the Game List.  Display can be
              restricted to a sub-set of the games meeting certain criteria.  A text entry below the  game  list
              allows  you  to  type a text that the game lines must contain in order to be displayed.  Games can
              also be selected based on their Elo PGN tag, as set in the `Load Game Options' dialog,  which  can
              be  popped  up  through the `Thresholds' button below the Game List.  Finally they can be selected
              based on containing a position similar to the one currently  displayed  in  the  main  window,  by
              pressing  the  'Position'  button  below  the  Game  List, (which searches the entire list for the
              position), or the 'Narrow' button (which only searches the already-selected games).   What  counts
              as  similar  enough  to  be selected can also be set in the `Load Game Options' dialog, and ranges
              from an exact match to just the same material.

       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.

       ICS/Chat Console
              This menu item opens a window in which you can interact with the ICS, so you don't have to use the
              messy xterm from which you launched XBoard for that.  The window has a text entry  at  the  bottom
              where  you can type your commands and messages unhindered by the stream of ICS output.  The latter
              will be displayed in a large pane above the input field, the ICS Console.  Up and down arrow  keys
              can  be  used  to  recall  previous  input  lines.   Typing  an <Esc> character in the input field
              transfers focus back to the board window (so you could operate the menus there through accelerator
              keys).   Typing  a printable character in the board window transfers focus back to the input field
              of the `ICS Chat/Console' window.

       Chats  There is a row of buttons at the top of the `ICS  Chat/Console'  dialog,  which  can  be  used  to
              navigate  between upto 5 'chats' with other ICS users (or channels).  These will switch the window
              to 'chat mode', where the ICS output pane is vertically split to divert messages from  a  specific
              user or ICS channel to the lower half.  Lines typed in the input field will then be interpreted as
              messages to be sent to that user or channel, (automatically  prefixed  with  the  apporpriate  ICS
              command  and user name) rather than as commands to the ICS.  Chats will keep collecting ICS output
              intended for them even when not displayed, and their buttons will turn orange to  alert  the  user
              there  has  been  activity.   Typing  <Tab> in the input field will switch to another active chat,
              giving priority to those with content you have not seen yet.

       New Chat
              Buttons for chats currently not assigned to a user or channel will carry the text `New Chat',  and
              pressing  them will switch to chat mode, enabling you to enter the user name or channel number you
              want to use it for.  Typing Ctrl-N in the input field is a keyboard equivalent.

       Chat partner
              To (re-)assign a chat, write the name of your chat partner,  the  channel  number,  or  the  words
              'shouts',  'whispers',  'cshouts' in the `Chat partner' text entry (ending with <Enter>!).  Typing
              Ctrl-O in the input field at the bottom of the window will open a chat with the person  that  last
              sent  you  a  'tell'  that  was  printed  in the ICS Console output pane.  The `ICS text menu' can
              contain a button `Open Chat (name)' that  can  be  used  to  open  a  chat  with  as  partner  the
              word/number you right-clicked in the output pane to pop up this menu.

       End Chat
              This button, only visible when the chat pane is open, will clear the `Chat partner' field, so that
              the chat can be assigned to a new user or channel.  Typing Ctrl-E in the input field is a keyboard
              equivalent.

       Hide   This  button,  only  visible when the chat pane is open, will close the latter, so you can use the
              input field to give commands to the ICS again.  Typing Ctrl-H in the input  field  is  a  keyboard
              equivalent.

       ICS text menu
              Brings up a menu that is user-configurable through the `icsMenu' option.  Buttons in this menu can
              sent pre-configured commands directly to the ICS, or can put partial commands in the  input  field
              of the `ICS Chat/Console' window, so that you can complete those with some text of your own before
              sending them to the ICS by pressing Enter.  This menu item can also be popped up by right-clicking
              in  the  text memos of the ICS Chat/Console window.  In that case the word that was clicked can be
              incorporated in the message sent to the ICS. E.g. to challenge a player whose name you click for a
              game, or prepare for sending him a message through a 'tell' commands.

       Edit ICS menu
              Brings  up an edit box with the definition of the `ICS text menu', so you can adapt its appearance
              to your needs.  The menu is defined by a semi-colon-separated list, each button through a pair  of
              items  in  it.   The  first item of each pair is the text on the button, the second the text to be
              sent when the button is pressed.  The word '$input' in the text will put that text  in  the  input
              field  of  the `ICS Chat/Console' with the cursor in that place, the word '$name' will be replaced
              by the word right-clicked to pop up the text menu.

       Edit Theme List
              Brings up an edit box with the definitions of the themes shown  in  the  listbox  of  the  `Board'
              dialog, so you can delete, re-order or alter themes defined previously.

       Board  Summons a dialog where you can customize the look of the chess board.

       White Piece Color
       Black Piece Color
       Light Square Color
       Dark Square Color
       Highlight Color
       Premove Highlight Color
              These items set the color of pieces, board squares and move highlights (borders or arrow).  Square
              colors are only used when the `Use Board Textures' option is off, the piece colors only when  `Use
              piece  bitmaps with their own colors' is off.  You can type the color as hexadecimally encoded RGB
              value preceded by '#', or adjust it through the R, G, B and D buttons to make it redder,  greener,
              bluer  or  darker.   A sample of the adjusted color will be displayed behind its text description;
              pressing this colored button restores the default value for the color.

       Flip Pieces Shogi Style
              With this option on XBoard will swap white and black pieces, when you flip the view of  the  board
              to  make white play downward.  This should be used with piece themes that do not distinguish sides
              by color, but by orientation.

       Mono Mode
              This option sets XBoard to pure black-and-white  display  (no  grey  scales,  and  thus  no  anti-
              aliasing).

       Logo Size
              Specifies  the width of the engine logos displayed next to the clocks, in pixels.  Setting it to 0
              suppresses the display of such logos.  The height of the logo will be half its width.  In the  GTK
              build  of  XBoard  any  non-zero value is equivalent, and the logos are always sized to 1/4 of the
              board width.

       Line Gap
              This option specifies the width of the grid lines that separate the squares, which change color on
              highlighting the move.  Setting it to 0 suppresses these lines, which in general looks better, but
              hides the square-border highlights, so that you would have to rely on other forms of highlighting.
              Setting the value to -1 makes XBoard choose a width by itself, depending on the square size.

       Use Board Textures
       Light-Squares Texture File
       Dark-Squares Texture File
              When  the  option  `Use  Board  Textures'  is set, the squares will not be drawn as evenly colored
              surfaces, but will be cut from a texture image, as specified by  the  `Texture  Files'.   Separate
              images  can  be  used  for  light and dark squares.  XBoard will try to cut the squares out of the
              texture image with as little overlap as possible, so they all look different.   The  name  of  the
              texture file can contain a size hint, e.g. `xqboard-9x10.png', alerting XBoard to the fact that it
              contains a whole-board image, out of which squares have to be cut in  register  with  the  nominal
              sub-division.

       Use external piece bitmaps with their own color
              When  this  option is on XBoard will ignore the piece-color settings, and draw the piece images in
              their original colors.  The piece-color settings would only work well for evenly  colored  pieces,
              such as the default theme.

       Directory with Pieces Images
              When  a directory is specified here, XBoard will first look for piece images (SVG or PNG files) in
              that directory, and fall back on the image from the default theme only for images it  cannot  find
              there.   An  image  file called White/BlackTile in the directory will be prefered as fall-back for
              missing pieces over the default image, however.

       Selectable themes
       New name for current theme
              When a theme name is specified while pressing 'OK', the combination of settings specified  in  the
              dialog  will  be  stored in XBoard's list of themes, which will be saved with the other options in
              the settings file (as the `themeNames' option).  This name  will  then  appear  in  the  selection
              listbox  next  time you open the dialog, so that you can recall the entire combination of settings
              by double-clicking it.

              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.   The  current  combination of these settings can be assigned a
              'theme' name by typing one in the text entry in the lower-left of  the  dialog,  and  closing  the
              latter  with  OK.   It will then appear in the themes listbox next time you open the dialog, where
              you can recall the complete settings combination with a double-click.

       Fonts  Pops up a dialog where you can set the fonts used in the main elements of various windows.   Pango
              font  names  can  be  typed  for each window type, and behind each text entry there are buttons to
              adjust the point size, and toggle the 'bold' or 'italic' attributes of the font.

       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. Set up the position by any means. (E.g. using `Edit Position' mode, pasing a FEN or  loading  a
              game and stepping to the position.)

              2. 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 analyze 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  `Tournament  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
       Edit Engine List
              Opens a window that shows the list of engines registered for use  by  XBoard,  together  with  the
              options  that  would  be used with them when you would select them from the `Load Engine' dialogs.
              You can then edit this list, e.g. for re-ordering the engines, or adding uncommon  options  needed
              by this engine (e.g. to cure non-compliant behavior).

              By  editing you can also organize the engines into collapsible groups.  By sandwiching a number of
              engine lines between lines "# NAME" and "# end", the thus  enclosed  engines  will  not  initially
              appear  in engine listboxes of other dialogs, but only the single line "# NAME" (where NAME can be
              an arbitrary text) will appear in their place.  Selecting that line will then  show  the  enclosed
              engines  in the listbox, which recursively can contain other groups.  The line with the group name
              will still present as a header, and selecting that line will collapse the group again,  and  makes
              the listbox go back to displaying the surrounding group.

       Load New 1st Engine
       Load New 2nd Engine
              Pops  up  a  dialog  where you can select or specify an engine to be loaded.  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!)

       Select engine from list
              The listbox shows the engines registered for use with  XBoard  before.   (This  means  XBoard  has
              information  on  the  engine  type,  whether  it plays book etc.  in the engine list stored in its
              settings file.)  Double-clicking an engine here will load it and close the dialog.  The  list  can
              also  contain  groups, indicated by a starting '#' sign.  Double-clicking such a group will 'open'
              it, and show the group contents in the listbox instead of the total list, with the group  name  as
              header.  Double-clicking the header will 'close' the group again.

       Nickname
       Use nickname in PGN player tags of engine-engine games
              When  a  `Nickname'  is  specified,  the engine will appear under this name in the `Select Engine'
              listbox.  Otherwise the name there will be a tidied version of the engine command.  The  user  can
              specify if the nickname is also to be used in PGN tags; normally the name engines report theselves
              would be used there.

       Engine Command
              The command needed to start the engine from the command line.  For  compliantly  installed  engine
              this is usually just a single word, the name of the engine package (e.g. 'crafty' or 'stockfish').
              Some engines need additional parameters on the command line.  For engines that are not in a  place
              where the system would expect them a full pathname can be specified, and usually the browse button
              for this oprion is the easiest way to obtain that.

       Engine Directory
              Compliant engines could run from any directory, and by default this option is proposed as '.', the
              current  directory.   If  a  (path)name  is  specified  here, XBoard will start the engine in that
              directory.  If you make the field empty, it will try to  derive  the  directory  from  the  engine
              command (if that was a path name).

       UCI    When  the  `UCI'  checkbox is ticked XBoard will assume the engine is of UCI type, and will invoke
              the corresponding adapter (as specified in the `adapterCommand'  option  stored  in  its  settings
              file)to  use  it.   By  default  this adapter is Polyglot, which must be installed from a separate
              package!

       USI/UCCI
              Ticking this checkbox informs XBoard that the engine is of USI or UCCI type (as Shogi  or  Xiangqi
              engines  often  are).  This makes XBoard invoke an adapter to run the engines, as specified by the
              `uxiAdapter' option stored in its settings file.  The UCI2WB program is an adapter that can handle
              both these engine types, as well as UCI.

       WB protocol v1
              Ticking  this  checkbox informs XBoard the engine is using an old version (1) of the communication
              protocol, so that it won't respond to a request to interrogate its properties.  XBoard then  won't
              even  try  that, saving you a wait of several seconds each time the engine is started.  Do not use
              this on state-of-the-art engines, as it would prevent XBoard from interrogating its  capabilities,
              so that many of its features might not work!

       Must not use GUI book
              By  default  XBoard assumes engines are responsible for their own opening book, but unticking this
              option makes XBoard consult its own book (as per `Opening-Book Filename') on behalf of the engine.

       Add this engine to the list
              By default XBoard would add the engine you specified, with all the given options to  its  list  of
              registered  engines  (kept  in  its settings file), when you press 'OK'.  Next time you could then
              simply select it from the listbox, or use the command "xboard -fe NICKNAME" to start  XBoard  with
              the  engine  and  accompanying  options.   New engines are always added at the end of the existing
              list, or, when you have opened a group in the `Select Engine' listbox, at the end of  that  group.
              But  can  be  re-ordered  later with the aid of the `Edit Engine List' menu item.  When you untick
              this checkbox before pressing 'OK' the engine will be loaded, but will not be added to the  engine
              list.

       Force current variant with this engine
              Ticking  this  option will make XBoard automatically start the engine in the current variant, even
              when XBoard was set for a different variant when you loaded the engine.  Useful  when  the  engine
              plays multiple variants, and you specifically want to play one different from its primary one.

       Engine #1 Settings
       Engine #2 Settings
              Pop  up a menu dialog to alter the settings specific to the applicable engine.  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 2.0.1.) For native XBoard engines this is less common.

       Common Settings
              Pops up a menu dialog 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.  The
              shifted `Alt+U' key is a keyboard equivalent.  Older XBoard/WinBoard engines might not respond  to
              these settings, but UCI engines always should.

       Maximum Number of CPUs per Engine
              Specifies  the  number  of search threads any engine can maximally use.  Do not set it to a number
              larger than the number of cores your computer has.  (Or half of it when you want  two  engines  to
              run simultaneously, as in a Two-Machines game with `Ponder Next Move' on.)

       Polyglot Directory

       Hash-Table Size
              Specifies  the  maximum  amount  of memory (RAM) each engine is allowed to use for storing info on
              positions it already searched, so it would not have to search them again.  Do not set it  so  that
              it  is more than half (or if you use two engines, more than a quarter) of the memory your computer
              has, or it would slow the engines down by an extreme amount.

       EGTB Path
              Sets the value of the `egtFormats' option, which specifies where on your computer  the  files  for
              End-Game  Tables  are  stored.  It must be a comma-separated list of path names, the path for each
              EGT   flavor   prefixed   with    the    name    of    the    latter    and    a    colon.    E.g.
              "nalimov:/home/egt/dtm,syzygy:/home/egt/dtz50".   The  path  names after the colon will be sent to
              the engines that say they can use the corresponding EGT flavor.

       EGTB Cache Size
              Specifies the amount of memory the engine should use to  buffer  end-game  information.   Together
              with the `Hash-Table Size' this determines how much memory the engine is allowed to use in total.

       Use GUI Book
       Opening-Book Filename
              The  `Opening-Book  Filename'  specifies an opening book in Polyglot format (usually a .bin file),
              from which XBoard can play moves on behalf of the engine.  This is also the book file on which the
              `Edit Book' and `Save Games as Book' menu items operate.  A checkbox `Use GUI Book' can be used to
              temporarily disable the book without losing the setting.  (This does not prevent editing or saving
              games on it!)

       Book Depth
       Book Variety
              The  way moves are selected from the book can be controlled by two options.  `Book Depth' controls
              for how deep into the game the book will be consulted (measured in full  moves).   `Book  Variety'
              controls  the  likelihood  of  playing weaker moves.  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.

       Engine #1 Has Own Book
       Engine #2 Has Own Book
              These checkboxes control on a per-engine basis whether XBoard will consult the  opening  book  for
              them.   If  ticked,  XBoard  will  never  play  moves  from  its  GUI  book, giving the engine the
              opportunity to use its own.  These options are automatically set  whenever  you  load  an  engine,
              based  on the setting of `Must not use GUI book' when you installed that through the `Load Engine'
              menu dialog.

       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.  Many engines won't respond to this.

       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
   Mute all Sounds
       Ticking this menu item toggles all sounds XBoard can make on or off, without losing their definitions.

   General Options
       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.

       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.

       Headers in Engine Output Window
              Controls the presence of column headers above the variations and associated information printed by
              the engine, on which you can issue button 3 clicks  to  open  or  close  the  columns.   Available
              columns are search depth, score, node count, time used, tablebase hits, search speed and selective
              search depth.

       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.

       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 on the first move of a PV or on the data fields left of it 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.  Clicking on later moves of the PV only
              temporarily show the moves for as long you keep the mouse button down, without adding them to  the
              game.

       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 yellow (non-captures) or red (captures).   Special  moves
              might  have  other colors (e.g. magenta for promotion, cyan for a partial move).  Legality testing
              must be on for XBoard to know how the piece moves, but with  legality  testing  off  some  engines
              would offer this information.

       Sticky Windows
              Controls  whether  the  auxiliary windows such as Engine Output, Move History and Evaluation Graph
              should keep touching XBoard's main window when you move the latter.

       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.)

       Top-Level Dialogs
              Controls whether the auxiliary windows will appear as icons in  the  task  bar  and  independently
              controllable, or whether they open and minimize all together with the main window.

       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 value of 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.

   Time Control
       Pops  up a sub-menu where you can set the time-control parameters interactively.  The shifted `Alt+T' key
       is a keyboard equivalent.

       classical
              Selects classical TC, where the game is devided into sessions of a certain number  of  moves,  and
              after each session the start time is again added to the clocks.

       incremental
              Selects  a  TC mode where the game will start with a base time on the clocks, and after every move
              an 'increment' will be added to it.

       fixed max
              Selects a TC mode where you have to make each move within a given time, and any left-over time  is
              not carried over to the next move.

       Divide entered times by 60
              To  allow entering of sub-minute initial time or sub-second increment, you can tick this checkbox.
              The initial time can then be entered in seconds, and the increment in units of 1/60 second.

       Moves per session
              Sets the duration of a session for classical time control.

       Initial time
              Time initially on the clock in classical or incremental time controls.  In classical time controls
              this time will also be added to the clock at the start of ach new session.

       Increment or max
              Time  to  be  added to the clock after every move in incremental TC mode.  Fore 'fixed maximum' TC
              mode, the clock will be set to this time before every move, irrespective of how much was  left  on
              that clock.

       Time-Odds factors
              When  these  options  are  set  to  1 the clocks of the players will be set according to the other
              specified TC parameters.  Players can be given unequal times by specifying a time-odds factor  for
              one  of them (or a different factor for both of them).  Any time received by that player will then
              be divided by that factor.

   Adjudications
       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.

       Detect all Mates
              When  this  option  is  set  XBoard will terminate the game on checkmate or stalemate, even if the
              engines would not do so.  Only works when `Test Legality' is on.

       Verify Engine Result Claims
              When this option is set XBoard will verify engine result claims,  (forfeiting  engines  that  make
              false claims), rather than naively beleiving the engine.  Only works when `Test Legality' is on.

       Draw if Insufficient Mating Material
              When  this option is set XBoard will terminate games with a draw result when so little material is
              left that checkmate is not longer possible.  In normal Chess this applies to KK, KNK, KBK and some
              positions  with multiple Bishops all on the same square shade.  Only works when `Test Legality' is
              on.

       Adjudicate Trivial Draws
              When this option is set XBoard will terminate games with a draw result  in  positions  that  could
              only  be  won  against an idiot.  In normal Chess this applies to KNNK, KRKR, KBKN, KNKN, and KBKB
              with Bishops on different square shades.  KQKQ will also be adjudicated a draw (possibly  unjustly
              so).  Only works when `Test Legality' is on.

       N-Move Rule
              When  this  option  is  set  to a value differnt from zero XBoard will terminate games with a draw
              result after the specified number of reversible moves (i.e. without captures or  pawn  pushes)  is
              made.

       N-fold Repeats
              When  this  option is set to a value larger than 1, XBoard will terminate games with a draw result
              when the same position has occurred the specified number of times.

       Draw after N Moves Total
              When this option is set to a value different from zero, XBoard will terminate games  with  a  draw
              result  after  that  many  moves  have been played.  Useful in automated engine-engine matches, to
              prevent one game between stubborn engines will soak up all your computer time.

       Win / Loss Threshold
              When this option is set to a value different from zero, XBoard will terminate games as a win  when
              both  engines  agree  the score is above the specified value (interpreted as centi-Pawn) for three
              successive moves.

       Negate Score of Engine #1
       Negate Score of Engine #2
              These options should be used with engines that report scores from the white point of view,  rather
              than  the  side-to-move  POV as XBoard would otherwise assume when adjudicating games based on the
              engine score.  When the engine is installed with the extra option `firstScoreIsAbs'  true  in  the
              engine  list  the  option would be automatically set when the engine is loaded throuhgh the Engine
              menu, or with the `fe' or `se' command-line option.

   ICS Options
       Pops up a menu dialog where options can be set that affect playing against an Internet Chess Server.

       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 while Playing
              Setting this option will make XBoard suppress display of any boards from observed games while  you
              are  playing.   Instead  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 for Background-Observed Game
              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.

       Auto-InputBox PopUp
              Controls  whether  the ICS Input Box will pop up automatically when you type a printable character
              to the board window in ICS mode.

       Quit After Game
              Controls whether XBoard will automatically disconnect  from  the  ICS  and  close  when  the  game
              currently in progress finishes.

       Premove
       Premove for White
       Premove for Black
       First White Move
       First Black Move
              If  the  `Premove' 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.

       Alarm
       Alarm Time
              When this option is on, an alarm sound is played when your clock counts down to the  `Alarm  Time'
              in  an  ICS  game.   (By default, the time is 5 seconds, but you can specify 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.

       -icsMenu string
              The  string defines buttons for the `ICS text menu'.  Each button definition consists of two semi-
              colon-terminated pieces of text, the first giving the label to  be  written  on  the  button,  the
              second the text that should be sent to the ICS when that button is pressed.  This second part (the
              'message') can contain linefeeds, so that you can send multiple  ICS  commands  with  one  button.
              Some  message  in  the  text,  all  starting with a $-sign, are treated special.  When the message
              contains '$input', it will not be sent directly to the ICS, but will be put in the input field  of
              the  `ICS  Chat/Console',  with the text cursor at the indicated place, so you can addsome text to
              the message before sending it off.  If such a message starts with '$add' it will be placed  behind
              any  text  that is already present in the input field, otherwise this field will be cleared first.
              The word '$name' occurring in the message will be replaced by the word that was  clicked  (through
              button  3)  in the ICS Chat/Console.  There are two special messages: '$chat' will open a new chat
              with the clicked word in the chat-partner  field,  while  '$copy'  will  copy  the  text  that  is
              currently-selected  in  the  ICS  Console to the clipboard.  An example of a text menu as it might
              occur in your settings file (where you could edit it):

                  -icsMenu {copy;$copy;
                  list players;who;
                  list games;games;
                  finger (player);finger $name;
                  bullet (player);match $name 1 1 r;
                  blitz (player);match $name 5 1 r;
                  rapid (player);match $name 30 0 r;
                  open chat (player);$chat;
                  tell (player);tell $name $input;
                  ask pieces;ptell Please give me a $input;
                  P;$add Pawn $input;
                  N;$add Knight $input;
                  B;$add Bishop $input;
                  R;$add Rook $input;
                  Q;$add Queen $input;
                  }

   Tournament Options
       Summons a dialog where you can set options important for playing automatic matches between  two  or  more
       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 the corresponding info 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
              From the Select Engine listbox you can pick an engine from your list of engines registered 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 accidentally, or change their order.  Typing names here
              yourself is not recommended, because names that do not exactly match one of  the  names  from  the
              selection listbox 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 in Match
              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 engines 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.

       Pause between Match Games
              Time  (in  milliseconds)  XBoard  waits  before  starting  a  new  game  after a previous match or
              tournament game finishes.  Such a waiting period is important for  engines  that  do  not  support
              'ping',  as  these  sometimes  still  produce  a  move long after the game finished because of the
              opponent resigning, which would be mistaken for a move in  the  next  game  if  that  had  already
              started.

       Save Tourney Games on
              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 this many Games
              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 books by 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'.

       Continue Later
              Pressing the `Continue Later' button confirms the current value of all items  in  the  dialog  and
              closes  it,  but  will  not  automatically start the tournament.  This allows you to return to the
              dialog later without losing the settings you already entered, to adjust paramenters through  other
              menu  dialogs.   (The `Common Engine Setting', `Time Control' and `General Options' dialogs can be
              accessed without closing the `Tournament Options' dialog through the  respective  buttons  at  the
              bottom of the latter.)

   Load Game Options
       Summons a dialog where you can set options that control loading of games.

       Auto-Display Tags
              Setting  this option causes a window to pop up on loading a game, displaying the PGN Tags for that
              game.

       Auto-Display Comment
              Setting this option causes a window to pop up whenever there is a comment to (or variation on) the
              currently displayed move.

       Auto-Play speed of loaded games
              This  option sets the number of seconds between moves when a newly loaded game is auto-playing.  A
              decimal fraction on the number is understood.  Setting it to -1 disables auto-play, staying in the
              start  position  of  the game after the loading completes.  Setting it to 0 will instantly move to
              the final position of the game.  The `Auto-Play speed' is also used to determine the analysis time
              for  each  move  during  `Analyze  Game'.  Note that auto-playing (including game analysis) can be
              stopped at any time through the `P' button above the board.

       options to use in game-viewer mode
              Specifies the options automatically set when XBoard is invoked with the option  `-viewer'  on  its
              command  line,  as  will  happen  when it is started in response to clicking a PGN game file.  The
              default setting would start XBoard without engine (due to the `-ncp' option), but if you  want  it
              to  automatically  start  with  your favorite engine, and automatically start analyzing, you could
              include the necessary options for that here (e.g. `-fe <engine> -initialMode analysis').

       Thresholds for position filtering in game list
              The following options can be set to limit the display of games in the `Game List' window to a sub-
              set, meeting the specified criteria.

       Elo of strongest player at least

       Elo of weakest player at least
              Games  with  an Elo tag specifying a lower rating for the mentioned player will not be diplayed in
              the `Game List'.

       No games before year
              Games with a Date tag before the specified year will not be diplayed in the `Game List'.

       Final nr of pieces
              A single number or a range (like 8-10) can be entered here, and will cause only  games  where  the
              number of men in the final position is in the given range will be diplayed in the `Game List'.

       Minimum nr consecutive positions
              Specifies  for how many consecutive positions the more fuzzy position-matching criteria have to be
              satisfied in order to count as a match.

       Search mode
       find position
              XBoard can select games for display in the `Game List'  based  on  whether  (in  addition  to  the
              conditions  on the PGN tags) they contain a position that matches the position currently displayed
              on the board, by pressing the `find position' or `narrow' buttons in the `Game List' window.   The
              `Search  mode'  setting  determines  what  counts  as match.  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 minimally 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, i.e. equal for
              white and black.

       narrow 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.

       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).

   Save Game Options
       Summons  a dialog where you can specify whether XBoard should automatically save files of games when they
       finish, and where and how to do that.

       Auto-Save Games
              When set XBoard will automatically save games on a file as they finish.  (Not when you abort  them
              by  pressing  `New  Game',  though!)   It  will  either prompt you for a filename, or use the file
              specified  by the `saveGameFile' option.

       Own Games Only
              Setting this option will exclude games by  others  observed  on  an  Internet  Chess  Server  from
              automatic saving.

       Save Games on File
              Name  of  the file on which games should be saved automatically.  Games are always appended to the
              file, and will never overwrite anything.

       Save Final Position on File
              When a name is defined, the final position of each game is appended to the mentioned file.

       PGN Event Header
              Specifies the name of the event used in the PGN event tag of new games that you create.

       Old Save Style
              Saves games in an obsolete and now long forgotten format, rather than as PGN. Never use  this  for
              orthodox Chess!

       Include Number Tag in tourney PGN
              When  on  this  option will cause the non-standard 'Number' tag to be written in any game saved in
              PGN format.  It will contain the unique number of the game in the tourney.   (As  opposed  to  the
              'Round' tag, which can be shared by many games.)

       Save Score/Depth Info in PGN
              When  on  this  option will cause the score and depth at which it was calculated by an engine, and
              (when available) thinking time to be saved with the move as a comment to the move, in  the  format
              {score/depth  time}.   Here 'score'is in pawn units from the point of view of the player that made
              the move, with two digits behind the decimal Pawn.

       Save Out-of-Book Info in PGN
              When on this option causes the score of the first move the engine made after coming out of book in
              an 'Annotator' PGN tag.

   Game List
       Pops  up  a  dialog where you can select the PGN tags that should appear on the lines in the `Game List',
       and their order.

   Sound Options
       Summons a dialog where you can specify the sounds that should accompany various events that can occur  in
       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.

       Sound Program
              Specifies the command XBoard should invoke to play sounds.  The specified text will be suffixed by
              the name of the sound file, and then run as a command.

       Sounds Directory
              Specifies the directory where XBoard will look for files with the names of the standard sounds.

       User WAV File
              When  we type a filename here, it can be assigned to the events by selecting `Above WAV File' from
              the drop downs.

       Try-Out Sound
       Play   The 'event' triggering the Try-Out sound is pressing of the `Play' button behind it.  This  allows
              you to judge the sounds.

   Save Settings Now
       Selecting  this  menu  item  causes  the  current  XBoard  settings  to  be written to the settings file,
       (.xboardrc in your home directory), 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, 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
       this ~/.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).

   Save Settings on Exit
       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.

       -shoMoveTime true/false
              When  this  option  is set the time that has been thought about the current move will be displayed
              behind the remaining time in parentheses (in seconds).  Default: false.

       -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).

       -epd   This  option puts XBoard in a special mode for solving EPD test-suites, for the entire duration of
              the session.  In this mode games are aborted after a single move, and that move will  be  compared
              with  the  best-move  or  avoid-move  from  the EPD position description from which the 'game' was
              started.  Playing a best move counts as a win, playing an avoid move as a loss,  and  playing  any
              other  move  counts  as a draw.  This option should be used in combination with match mode, and an
              EPD file of starting positions with an auto-incrementing index.  Color  assignment  will  be  such
              that  the first engine plays all moves, and the second engine will be never involved.  The results
              for individual positions, as well as the time used for solving them, will be reported in the lower
              pane of the Engine Output window.

       -fcp or -firstChessProgram program
       -scp or -secondChessProgram program
              Name of first and second chess engine, respectively.  A second chess engine is started only in Two
              Machines (match) mode, or in Analyze mode with two engines.  The second engine is by  default  the
              same as the first.  Default for the first engine: `fairymax'.

       -fe or -firstEngine nickname
       -se or -secondEngine nickname
              This  is an alternative to the `fcp' and `scp' options for specifying the first and second engine,
              for engines that were already registered (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.)

       -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.

       -fischerCastling
              Specifies Fischer castling (as in Chess960) should be enabled in variants that normally would  not
              have it.  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 a 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 a  UCCI  or
              USI adapter, as the need arises.

       -adapterCommand string
              The  string  contains  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.  The latter 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 versions 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" and "gaviota" DTM tablebases, syzygy
              DTZ tablebases and "scorpio" bitbases.  Default: "".

       -firstChessProgramNames={names}
              This option lets you customize the listbox with chess-engine  names  that  appears  in  the  `Load
              Engine' and `Tournament 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 number 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 in other ways, (e.g. deleting engines),  use  the
              menu item `Edit Engine List' in the `Engine' menu.

   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 tourney.   Games  currently
              playing  are listed as *, while a space indicates a game that is not yet played.  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,
              or after the 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 instead 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 played when a player other than yourself makes a move.  Default: "$".

       -soundRoar filename
              This sound is played when a Lion makes a hit-and-run or double capture/ Default: "" (no sound).

       -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.

       -positionDir directory
              Specifies the directory where file browsing should start when using the `Load Position' menu item.

       -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.

       -pgnTimeLeft true/false
              If this option is set, XBoard will save the remaining clock time for  the  player  that  has  just
              moved  as part of the `pgnExtendedInfo', rather than the time that player thought about his latest
              move.  Default: false.

       -pgnEventHeader string
              Default: false.  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  succesful  -settingsFile  /  -ini
              command,  if  any, and in /etc/xboard/xboard.conf otherwise.  Usualy the latter is only accessible
              for the system administrator, though, and will be used to contain  system-wide  default  settings,
              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
       -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'.   For  a  human  player  it  will  look  for  a  file
              <username>.png in this directory, but only when ~/.logo.png does not provide one.

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

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

       -monoMouse true/false
              When  set  button  1 clicks on empty squares in Edit Position mode will be interpreted as button 3
              clicks, so they place a piece.  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.

       -analysisBell N
              When N is non-zero, the Move Sound will be played whenever a new PV arrives in analysis mode after
              more than N seconds of analysis.  Default: 0.

       -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

       -tagsFont font
              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.

       -commentFont font
              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.

       -icsFont font
              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.

       -moveHistoryFont font
              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.

       -gameListFont font
              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  first  ty  to  use  an  image White/BlackTile.svg in that same directory, and if that is not
              present either 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.  Default: "".

       -inscriptions utf8string
              The positions in the utf8string correspond to XBoard's piece types, and for each type a glyph  can
              be  defined.   This glyph will then be rendered on top of the image for the piece.  This is useful
              in combination with the White/BlackTile.svg images, which could be the  image  of  a  blank  Shogi
              tile, for writing the kanji piece name on top of it on the fly.  Default: "".

       -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, a button 3 click left of 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 it 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.  A button 3 click 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!

   Install options
       --show-config parameter
              When called with this option, XBoard will close  immediately  after  printing  the  value  of  the
              indicated  configuration  parameter, or, when no parameter was given, after printing a list of all
              such parameters.  Currently the only valid values for parameter are Datadir and Sysconfdir.   This
              option  can  be  used by install scripts for board themes to figure out where the currently active
              XBoard stores its data.

       -date timestamp
       -saveDate timestamp
              These options specify an epoch as an integer number.  The `saveDate' option is written  by  XBoard
              in  the settings file every time the settings are saved, with the current time, so that later runs
              of XBoard can know this.  The `date' option can be included in settings  files  to  indicate  when
              lines following it were added to those files.  Some options will be ignored if the epoch specified
              by the latest `date' option predates the -saveDate setting (implying  they  must  have  been  seen
              before).

       -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 autoInstall list to limit this automatic adding of engines based on
              the chess variant they play.

       -addMasterOption string
              Adds the mentioned string as an additional line of XBoard's master settings file, after  adding  a
              line  with  a  `date'  option to timestamp it.  Intended to add options of the 'install' type (see
              below) to the master file, which will then be processed by any XBoard that has not seen them since
              it last saved its settings.

       -autoClose
              The  presence  of  this  option cause XBoard to close immediately after processing all its options
              (from settings file and command line).  Typically used from install scripts together with  options
              that  change  XBoard's  settings  files,  so  that  XBoard  can  be  run in batch mode rather than
              interactively.

       -installEngine string
              Adds the given string as an additional line to the value of  the  `firstChessProgramNames'  option
              when the -saveDate setting preceeds the -date setting.  Intended for adding to the master settings
              file with the aid of  -addMasterOption  in  the  install  script  of  engines,  as  a  method  for
              broadcasting  the  presence  of  a  new engine to all users, which would then see it automatically
              registered with XBoard.  Made obsolete by the advent of the plugin standard (see the `autoInstall'
              option),  which broadcasts such presence in a non-XBoard-specific way by dropping *.eng files in a
              certain system directory.

       -installTheme string
              Adds the given string as an additional line to the  value  of  the  -themeNames  option  when  the
              -saveDate  setting  preceeds  the  -date setting.  Intended for adding to the master settings file
              with the aid of -addMasterOption in the install script of board graphics themes, as a  method  for
              broadcasting  the  availability  of  a new theme to all users, who would then see the theme appear
              automatically in the listbox in the View Board menu dialog next time they run XBoard.

   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 append 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   (sometimes  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 diagonally
                  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)
                  great         Great Shatranj, a 10x8 variant without sliders
                  grand         Grand Chess, on 10x10 with Capablanca pieces
                  lion          Mighty-Lion Chess, with a multi-capturing Lion
                  elven         Eleven Chess, with Lion and crowned sliders on 10x10
                  chu           Chu Shogi, historic 12x12 variant with 2x46 pieces
                  fairy         A catchall variant in which all piece types
                                known to XBoard can participate (8x8)
                  unknown       Catchall for other unknown variants

              In the shuffle variants, XBoard 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.  Berolina and cylinder chess are only partially supported, and can only be played with
              legality testing off.

              Apart  from  these  standard  variants,  engines  can define variants of arbitrary names, briefing
              XBoard transparently on the rules for piece movement, board size and initial setup, so  that  they
              work  nearly  as  well as fully-supported standard variants.  (But obviously only while using that
              engine.)  The user might have to alter the adjudication settings for some variants, however.  E.g.
              it  makes  no sense to adjudicate a draw after 50 reversible moves in variants that have a 64-move
              rule, or no similar rule at all.

              Default: "normal". Except when the first engine gave an explicit list of variants it supports, and
              'normal'  is  not  amongst those.  In that case the first variant the engine mentioned it did play
              will be chosen.

       -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.  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.  The string argument
              has to specify an even number of pieces (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  FEACWMOHIJGDVLSU,  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 fewer characters in the string than XBoard has pieces,
              the pieces not mentioned will get assigned a period, and will not be usable in the  variant.   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 to 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).  By default the second 11 pieces
              known to XBoard are the promoted forms of the first  11.   A  piece  specified  by  the  character
              combination  ^  plus letter will be assumed to be the promoted form of the piece indicated by that
              letter, and get a '+' assigned.  To get around the limitation of the alphabet, piece IDs can  also
              be  'dressed  letters', i.e. a single letter (upper case for white, lower case for black) followed
              by a single quote or an exclamation point.  Default: "" (meaning the default for  the  variant  is
              used).

       -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
       both  that  copyright  notice and this permission notice appear in supporting documentation, and that the
       name of Digital not be used in advertising or  publicity  pertaining  to  distribution  of  the  software
       without specific, written prior permission.

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

       Enhancements  copyright  (C) 1992-2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014,
       2015, 2016 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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       Permission  is  granted  to copy and distribute modified versions of this manual under the conditions for
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       instead of in the original English.

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              Additional terms, permissive or non-permissive, may be stated in the form of a separately  written
              license, or stated as exceptions; the above requirements apply either way.

       Termination.
              You  may  not  propagate or modify a covered work except as expressly provided under this License.
              Any attempt otherwise to propagate or modify it is void, and  will  automatically  terminate  your
              rights  under  this  License  (including  any patent licenses granted under the third paragraph of
              section 11).

              However, if you cease all violation of this License, then your license from a particular copyright
              holder  is  reinstated  (a)  provisionally,  unless  and until the copyright holder explicitly and
              finally terminates your license, and (b) permanently, if the copyright holder fails to notify  you
              of the violation by some reasonable means prior to 60 days after the cessation.

              Moreover,  your  license  from  a  particular  copyright  holder  is reinstated permanently if the
              copyright holder notifies you of the violation by some reasonable means, this is  the  first  time
              you  have  received notice of violation of this License (for any work) from that copyright holder,
              and you cure the violation prior to 30 days after your receipt of the notice.

              Termination of your rights under this section does not terminate the licenses of parties who  have
              received  copies  or  rights from you under this License.  If your rights have been terminated and
              not permanently reinstated, you do not qualify to receive new licenses for the same material under
              section 10.

       Acceptance Not Required for Having Copies.
              You  are  not  required  to  accept this License in order to receive or run a copy of the Program.
              Ancillary propagation of a covered work occurring solely as a consequence  of  using  peer-to-peer
              transmission  to receive a copy likewise does not require acceptance.  However, nothing other than
              this License grants you permission to  propagate  or  modify  any  covered  work.   These  actions
              infringe  copyright  if  you do not accept this License.  Therefore, by modifying or propagating a
              covered work, you indicate your acceptance of this License to do so.

       Automatic Licensing of Downstream Recipients.
              Each time you convey a covered work, the recipient  automatically  receives  a  license  from  the
              original  licensors, to run, modify and propagate that work, subject to this License.  You are not
              responsible for enforcing compliance by third parties with this License.

              An  ``entity  transaction''  is  a  transaction  transferring  control  of  an  organization,   or
              substantially  all  assets  of  one, or subdividing an organization, or merging organizations.  If
              propagation of a covered work results from an entity transaction, each party to  that  transaction
              who  receives  a  copy  of  the  work  also  receives  whatever  licenses  to the work the party's
              predecessor in interest had or could give under the previous paragraph, plus a right to possession
              of  the  Corresponding Source of the work from the predecessor in interest, if the predecessor has
              it or can get it with reasonable efforts.

              You may not impose any further restrictions on the exercise of  the  rights  granted  or  affirmed
              under  this  License.  For example, you may not impose a license fee, royalty, or other charge for
              exercise of rights granted under this License, and you may not initiate  litigation  (including  a
              cross-claim  or  counterclaim in a lawsuit) alleging that any patent claim is infringed by making,
              using, selling, offering for sale, or importing the Program or any portion of it.

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

              A contributor's ``essential patent claims'' are all patent  claims  owned  or  controlled  by  the
              contributor,  whether  already  acquired  or  hereafter  acquired, that would be infringed by some
              manner, permitted by this License, of making, using, or selling its contributor  version,  but  do
              not  include  claims  that would be infringed only as a consequence of further modification of the
              contributor version.  For purposes of this definition, ``control'' includes  the  right  to  grant
              patent sublicenses in a manner consistent with the requirements of this License.

              Each  contributor  grants  you  a  non-exclusive, worldwide, royalty-free patent license under the
              contributor's essential patent claims, to make, use, sell, offer for sale,  import  and  otherwise
              run, modify and propagate the contents of its contributor version.

              In  the  following  three paragraphs, a ``patent license'' is any express agreement or commitment,
              however denominated, not to enforce a patent (such as an express permission to practice  a  patent
              or  covenant  not  to sue for patent infringement).  To ``grant'' such a patent license to a party
              means to make such an agreement or commitment not to enforce a patent against the party.

              If you convey a covered work, knowingly relying on a patent license, and the Corresponding  Source
              of  the  work  is  not  available  for  anyone to copy, free of charge and under the terms of this
              License, through a publicly available network server or other readily accessible means,  then  you
              must  either  (1)  cause  the  Corresponding  Source to be so available, or (2) arrange to deprive
              yourself of the benefit of the patent license for this particular  work,  or  (3)  arrange,  in  a
              manner  consistent  with  the  requirements  of  this  License,  to  extend  the patent license to
              downstream recipients.  ``Knowingly relying'' means you have actual knowledge that,  but  for  the
              patent  license,  your  conveying  the  covered  work in a country, or your recipient's use of the
              covered work in a country, would infringe one or more identifiable patents in  that  country  that
              you have reason to believe are valid.

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

              A  patent  license  is ``discriminatory'' if it does not include within the scope of its coverage,
              prohibits the exercise of, or is conditioned on the non-exercise of one or more of the rights that
              are specifically granted under this License.  You may not convey a covered work if you are a party
              to an arrangement with a third party that is in the business of distributing software, under which
              you  make  payment  to the third party based on the extent of your activity of conveying the work,
              and under which the third party grants, to any of the parties who would receive the  covered  work
              from  you,  a  discriminatory  patent  license  (a)  in connection with copies of the covered work
              conveyed by you (or copies made from those copies), or (b) primarily for and  in  connection  with
              specific  products  or  compilations  that  contain the covered work, unless you entered into that
              arrangement, or that patent license was granted, prior to 28 March 2007.

              Nothing in this License shall be construed as excluding or limiting any implied license  or  other
              defenses to infringement that may otherwise be available to you under applicable patent law.

       No Surrender of Others' Freedom.
              If  conditions are imposed on you (whether by court order, agreement or otherwise) that contradict
              the conditions of this License, they do not excuse you from the conditions of  this  License.   If
              you  cannot  convey  a  covered  work  so as to satisfy simultaneously your obligations under this
              License and any other pertinent obligations, then as a consequence you may not convey it  at  all.
              For  example,  if  you agree to terms that obligate you to collect a royalty for further conveying
              from those to whom you convey the Program, the only way you could satisfy  both  those  terms  and
              this License would be to refrain entirely from conveying the Program.

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

       Revised Versions of this License.
              The Free Software Foundation may publish revised and/or new versions of  the  GNU  General  Public
              License  from  time  to time.  Such new versions will be similar in spirit to the present version,
              but may differ in detail to address new problems or concerns.

              Each version is given a distinguishing version number.  If the Program specifies  that  a  certain
              numbered  version  of  the  GNU General Public License ``or any later version'' applies to it, you
              have the option of following the terms and conditions either of that numbered version  or  of  any
              later  version  published  by  the  Free  Software  Foundation.  If the Program does not specify a
              version number of the GNU General Public License, you may choose any version ever published by the
              Free Software Foundation.

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

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

       Disclaimer of Warranty.
              THERE  IS  NO  WARRANTY  FOR  THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
              OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE  THE  PROGRAM  ``AS
              IS'' WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE
              IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS TO
              THE  QUALITY  AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU
              ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

       Limitation of Liability.
              IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY  COPYRIGHT  HOLDER,
              OR  ANY  OTHER  PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU
              FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES  ARISING  OUT  OF
              THE  USE  OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
              RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE  OF  THE  PROGRAM  TO
              OPERATE  WITH  ANY  OTHER  PROGRAMS),  EVEN  IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
              POSSIBILITY OF SUCH DAMAGES.

       Interpretation of Sections 15 and 16.
              If the disclaimer of warranty and limitation of liability provided above  cannot  be  given  local
              legal  effect  according  to their terms, reviewing courts shall apply local law that most closely
              approximates an absolute waiver of all civil liability in connection with the  Program,  unless  a
              warranty or assumption of liability accompanies a copy of the Program in return for a fee.

              If  you  develop  a new program, and you want it to be of the greatest possible use to the public,
              the best way to achieve this is to make it free  software  which  everyone  can  redistribute  and
              change under these terms.

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

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

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

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

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

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

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

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

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

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

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