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.

MENUS, BUTTONS, AND KEYS

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

       New Shuffle Game
              Similar to `New Game', but allows you to  specify  a  particular  initial  position
              (according  to  a  standardized  numbering  system)  in  chess  variants  which use
              randomized opening positions (e.g. Chess960).

       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

       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
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       Permission is granted to copy and distribute modified versions of this  manual  under  the
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              You  may  charge  any  price or no price for each copy that you convey, and you may
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       Conveying Modified Source Versions.
              You may convey a work based on the Program, or the modifications to produce it from
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              The work must carry prominent notices stating that you modified it,  and  giving  a
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              You  must  license  the  entire  work, as a whole, under this License to anyone who
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              If the work has interactive user interfaces, each must  display  Appropriate  Legal
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              A compilation of a covered work with other separate and  independent  works,  which
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       Conveying Non-Source Forms.
              You may convey a covered work in object code form under the terms of sections 4 and
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              Convey the object code in, or embodied in, a physical product (including a physical
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              Convey the object code in, or embodied in, a physical product (including a physical
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              Convey  individual  copies  of  the object code with a copy of the written offer to
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              Convey the object code by offering access from a designated place (gratis or for  a
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              Convey  the  object code using peer-to-peer transmission, provided you inform other
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              A  separable  portion  of  the  object code, whose source code is excluded from the
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              A  ``User  Product'' is either (1) a ``consumer product'', which means any tangible
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              ``Installation  Information''  for  a  User  Product means any methods, procedures,
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              If you convey an object code work under this section in, or with,  or  specifically
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              if neither you nor any third party retains the ability to install  modified  object
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              The  requirement to provide Installation Information does not include a requirement
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              Corresponding Source conveyed, and Installation  Information  provided,  in  accord
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              special password or key for unpacking, reading or copying.

       Additional Terms.
              ``Additional  permissions''  are terms that supplement the terms of this License by
              making exceptions from one or more of its conditions.  Additional permissions  that
              are  applicable to the entire Program shall be treated as though they were included
              in this License, to the extent that  they  are  valid  under  applicable  law.   If
              additional  permissions  apply  only  to part of the Program, that part may be used
              separately under those permissions, but the entire Program remains governed by this
              License without regard to the additional permissions.

              When  you  convey  a  copy  of  a  covered  work, you may at your option remove any
              additional permissions from that  copy,  or  from  any  part  of  it.   (Additional
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              modify the work.)  You may place additional permissions on material, added  by  you
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              Notwithstanding  any  other  provision  of  this License, for material you add to a
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              supplement the terms of this License with terms:

              Disclaiming  warranty  or limiting liability differently from the terms of sections
              15 and 16 of this License; or

              Requiring preservation of specified reasonable legal notices or author attributions
              in  that material or in the Appropriate Legal Notices displayed by works containing
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              Prohibiting misrepresentation of the origin of that  material,  or  requiring  that
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              Limiting the use for publicity purposes of names of licensors  or  authors  of  the
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              Declining  to  grant  rights  under  trademark  law  for  use  of some trade names,
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              Requiring indemnification of licensors and authors of that material by  anyone  who
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              All  other  non-permissive additional terms are considered ``further restrictions''
              within the meaning of section 10.  If the Program as you received it, or  any  part
              of  it,  contains a notice stating that it is governed by this License along with a
              term that is a further restriction,  you  may  remove  that  term.   If  a  license
              document  contains a further restriction but permits relicensing or conveying under
              this License, you may add to a covered work material governed by the terms of  that
              license  document,  provided  that  the  further  restriction does not survive such
              relicensing or conveying.

              If you add terms to a covered work in accord with this section, you must place,  in
              the  relevant source files, a statement of the additional terms that apply to those
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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'.