xref: /dports/news/fidogate4/fidogate-4.4.10/doc/texinfo.tex

%
% Modified to use PostScript fonts (mj@fido.de)
%

%% TeX macros to handle texinfo files

%   Copyright (C) 1985, 86, 88, 90, 91, 92, 93, 1994 Free Software Foundation, Inc.

%This texinfo.tex file 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 2, or (at
%your option) any later version.

%This texinfo.tex file 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 texinfo.tex file; see the file COPYING.  If not, write
%to the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
%USA.


%In other words, you are welcome to use, share and improve this program.
%You are forbidden to forbid anyone else to use, share and improve
%what you give them.   Help stamp out software-hoarding!

% This automatically updates the version number based on RCS.
\def\deftexinfoversion$#1: #2 ${\def\texinfoversion{#2/K}}
\deftexinfoversion$Revision: 4.0 $
\message{Loading texinfo package [PostScript Version \texinfoversion]:}

% Print the version number if in a .fmt file.
\everyjob{\message{[Texinfo version \texinfoversion]}\message{}}

% Save some parts of plain tex whose names we will redefine.

\let\ptextilde=\~
\let\ptexlbrace=\{
\let\ptexrbrace=\}
\let\ptexdots=\dots
\let\ptexdot=\.
\let\ptexstar=\*
\let\ptexend=\end
\let\ptexbullet=\bullet
\let\ptexb=\b
\let\ptexc=\c
\let\ptexi=\i
\let\ptext=\t
\let\ptexl=\l
\let\ptexL=\L

\def\tie{\penalty 10000\ }     % Save plain tex definition of ~.
\let\~ = \tie                  % And make it available as @~.

\message{Basics,}
\chardef\other=12

% If this character appears in an error message or help string, it
% starts a new line in the output.
\newlinechar = `^^J

% Set up fixed words for English.
\ifx\putwordChapter\undefined{\gdef\putwordChapter{Chapter}}\fi%
\def\putwordInfo{Info}%
\ifx\putwordSee\undefined{\gdef\putwordSee{See}}\fi%
\ifx\putwordsee\undefined{\gdef\putwordsee{see}}\fi%
\ifx\putwordfile\undefined{\gdef\putwordfile{file}}\fi%
\ifx\putwordpage\undefined{\gdef\putwordpage{page}}\fi%
\ifx\putwordsection\undefined{\gdef\putwordsection{section}}\fi%
\ifx\putwordSection\undefined{\gdef\putwordSection{Section}}\fi%
\ifx\putwordTableofContents\undefined{\gdef\putwordTableofContents{Table of Contents}}\fi%
\ifx\putwordShortContents\undefined{\gdef\putwordShortContents{Short Contents}}\fi%
\ifx\putwordAppendix\undefined{\gdef\putwordAppendix{Appendix}}\fi%

% Ignore a token.
%
\def\gobble#1{}

\hyphenation{ap-pen-dix}
\hyphenation{mini-buf-fer mini-buf-fers}
\hyphenation{eshell}

% Margin to add to right of even pages, to left of odd pages.
\newdimen \bindingoffset  \bindingoffset=0pt
\newdimen \normaloffset   \normaloffset=\hoffset
\newdimen\pagewidth \newdimen\pageheight
\pagewidth=\hsize \pageheight=\vsize

% Sometimes it is convenient to have everything in the transcript file
% and nothing on the terminal.  We don't just call \tracingall here,
% since that produces some useless output on the terminal.
%
\def\gloggingall{\begingroup \globaldefs = 1 \loggingall \endgroup}%
\def\loggingall{\tracingcommands2 \tracingstats2
   \tracingpages1 \tracingoutput1 \tracinglostchars1
   \tracingmacros2 \tracingparagraphs1 \tracingrestores1
   \showboxbreadth\maxdimen\showboxdepth\maxdimen
}%

%---------------------Begin change-----------------------
%
%%%% For @cropmarks command.
% Dimensions to add cropmarks at corners Added by P. A. MacKay, 12 Nov. 1986
%
\newdimen\cornerlong \newdimen\cornerthick
\newdimen \topandbottommargin
\newdimen \outerhsize \newdimen \outervsize
\cornerlong=1pc\cornerthick=.3pt        % These set size of cropmarks
\outerhsize=7in
%\outervsize=9.5in
% Alternative @smallbook page size is 9.25in
\outervsize=9.25in
\topandbottommargin=.75in
%
%---------------------End change-----------------------

% \onepageout takes a vbox as an argument.  Note that \pagecontents
% does insertions itself, but you have to call it yourself.
\chardef\PAGE=255  \output={\onepageout{\pagecontents\PAGE}}
\def\onepageout#1{\hoffset=\normaloffset
\ifodd\pageno  \advance\hoffset by \bindingoffset
\else \advance\hoffset by -\bindingoffset\fi
{\escapechar=`\\\relax % makes sure backslash is used in output files.
\shipout\vbox{{\let\hsize=\pagewidth \makeheadline} \pagebody{#1}%
{\let\hsize=\pagewidth \makefootline}}}%
\advancepageno \ifnum\outputpenalty>-20000 \else\dosupereject\fi}

%%%% For @cropmarks command %%%%

% Here is a modification of the main output routine for Near East Publications
% This provides right-angle cropmarks at all four corners.
% The contents of the page are centerlined into the cropmarks,
% and any desired binding offset is added as an \hskip on either
% site of the centerlined box.  (P. A. MacKay, 12 November, 1986)
%
\def\croppageout#1{\hoffset=0pt % make sure this doesn't mess things up
{\escapechar=`\\\relax % makes sure backslash is used in output files.
                 \shipout
                 \vbox to \outervsize{\hsize=\outerhsize
                 \vbox{\line{\ewtop\hfill\ewtop}}
                 \nointerlineskip
                 \line{\vbox{\moveleft\cornerthick\nstop}
                       \hfill
                       \vbox{\moveright\cornerthick\nstop}}
                 \vskip \topandbottommargin
                 \centerline{\ifodd\pageno\hskip\bindingoffset\fi
                        \vbox{
                        {\let\hsize=\pagewidth \makeheadline}
                        \pagebody{#1}
                        {\let\hsize=\pagewidth \makefootline}}
                        \ifodd\pageno\else\hskip\bindingoffset\fi}
                 \vskip \topandbottommargin plus1fill minus1fill
                 \boxmaxdepth\cornerthick
                 \line{\vbox{\moveleft\cornerthick\nsbot}
                       \hfill
                       \vbox{\moveright\cornerthick\nsbot}}
                 \nointerlineskip
                 \vbox{\line{\ewbot\hfill\ewbot}}
        }}
  \advancepageno
  \ifnum\outputpenalty>-20000 \else\dosupereject\fi}
%
% Do @cropmarks to get crop marks
\def\cropmarks{\let\onepageout=\croppageout }

\def\pagebody#1{\vbox to\pageheight{\boxmaxdepth=\maxdepth #1}}
{\catcode`\@ =11
\gdef\pagecontents#1{\ifvoid\topins\else\unvbox\topins\fi
\dimen@=\dp#1 \unvbox#1
\ifvoid\footins\else\vskip\skip\footins\footnoterule \unvbox\footins\fi
\ifr@ggedbottom \kern-\dimen@ \vfil \fi}
}

%
% Here are the rules for the cropmarks.  Note that they are
% offset so that the space between them is truly \outerhsize or \outervsize
% (P. A. MacKay, 12 November, 1986)
%
\def\ewtop{\vrule height\cornerthick depth0pt width\cornerlong}
\def\nstop{\vbox
  {\hrule height\cornerthick depth\cornerlong width\cornerthick}}
\def\ewbot{\vrule height0pt depth\cornerthick width\cornerlong}
\def\nsbot{\vbox
  {\hrule height\cornerlong depth\cornerthick width\cornerthick}}

% Parse an argument, then pass it to #1.  The argument is the rest of
% the input line (except we remove a trailing comment).  #1 should be a
% macro which expects an ordinary undelimited TeX argument.
%
\def\parsearg#1{%
  \let\next = #1%
  \begingroup
    \obeylines
    \futurelet\temp\parseargx
}

% If the next token is an obeyed space (from an @example environment or
% the like), remove it and recurse.  Otherwise, we're done.
\def\parseargx{%
  % \obeyedspace is defined far below, after the definition of \sepspaces.
  \ifx\obeyedspace\temp
    \expandafter\parseargdiscardspace
  \else
    \expandafter\parseargline
  \fi
}

% Remove a single space (as the delimiter token to the macro call).
{\obeyspaces %
 \gdef\parseargdiscardspace {\futurelet\temp\parseargx}}

{\obeylines %
  \gdef\parseargline#1^^M{%
    \endgroup % End of the group started in \parsearg.
    %
    % First remove any @c comment, then any @comment.
    % Result of each macro is put in \toks0.
    \argremovec #1\c\relax %
    \expandafter\argremovecomment \the\toks0 \comment\relax %
    %
    % Call the caller's macro, saved as \next in \parsearg.
    \expandafter\next\expandafter{\the\toks0}%
  }%
}

% Since all \c{,omment} does is throw away the argument, we can let TeX
% do that for us.  The \relax here is matched by the \relax in the call
% in \parseargline; it could be more or less anything, its purpose is
% just to delimit the argument to the \c.
\def\argremovec#1\c#2\relax{\toks0 = {#1}}
\def\argremovecomment#1\comment#2\relax{\toks0 = {#1}}

% \argremovec{,omment} might leave us with trailing spaces, though; e.g.,
%    @end itemize  @c foo
% will have two active spaces as part of the argument with the
% `itemize'.  Here we remove all active spaces from #1, and assign the
% result to \toks0.
%
% This loses if there are any *other* active characters besides spaces
% in the argument -- _ ^ +, for example -- since they get expanded.
% Fortunately, Texinfo does not define any such commands.  (If it ever
% does, the catcode of the characters in questionwill have to be changed
% here.)  But this means we cannot call \removeactivespaces as part of
% \argremovec{,omment}, since @c uses \parsearg, and thus the argument
% that \parsearg gets might well have any character at all in it.
%
\def\removeactivespaces#1{%
  \begingroup
    \ignoreactivespaces
    \edef\temp{#1}%
    \global\toks0 = \expandafter{\temp}%
  \endgroup
}

% Change the active space to expand to nothing.
%
\begingroup
  \obeyspaces
  \gdef\ignoreactivespaces{\obeyspaces\let =\empty}
\endgroup


\def\flushcr{\ifx\par\lisppar \def\next##1{}\else \let\next=\relax \fi \next}

%% These are used to keep @begin/@end levels from running away
%% Call \inENV within environments (after a \begingroup)
\newif\ifENV \ENVfalse \def\inENV{\ifENV\relax\else\ENVtrue\fi}
\def\ENVcheck{%
\ifENV\errmessage{Still within an environment.  Type Return to continue.}
\endgroup\fi} % This is not perfect, but it should reduce lossage

% @begin foo  is the same as @foo, for now.
\newhelp\EMsimple{Type <Return> to continue.}

\outer\def\begin{\parsearg\beginxxx}

\def\beginxxx #1{%
\expandafter\ifx\csname #1\endcsname\relax
{\errhelp=\EMsimple \errmessage{Undefined command @begin #1}}\else
\csname #1\endcsname\fi}

% @end foo executes the definition of \Efoo.
%
\def\end{\parsearg\endxxx}
\def\endxxx #1{%
  \removeactivespaces{#1}%
  \edef\endthing{\the\toks0}%
  %
  \expandafter\ifx\csname E\endthing\endcsname\relax
    \expandafter\ifx\csname \endthing\endcsname\relax
      % There's no \foo, i.e., no ``environment'' foo.
      \errhelp = \EMsimple
      \errmessage{Undefined command `@end \endthing'}%
    \else
      \unmatchedenderror\endthing
    \fi
  \else
    % Everything's ok; the right environment has been started.
    \csname E\endthing\endcsname
  \fi
}

% There is an environment #1, but it hasn't been started.  Give an error.
%
\def\unmatchedenderror#1{%
  \errhelp = \EMsimple
  \errmessage{This `@end #1' doesn't have a matching `@#1'}%
}

% Define the control sequence \E#1 to give an unmatched @end error.
%
\def\defineunmatchedend#1{%
  \expandafter\def\csname E#1\endcsname{\unmatchedenderror{#1}}%
}


% Single-spacing is done by various environments (specifically, in
% \nonfillstart and \quotations).
\newskip\singlespaceskip \singlespaceskip = 12.5pt
\def\singlespace{%
  % Why was this kern here?  It messes up equalizing space above and below
  % environments.  --karl, 6may93
  %{\advance \baselineskip by -\singlespaceskip
  %\kern \baselineskip}%
  \setleading \singlespaceskip
}

%% Simple single-character @ commands

% @@ prints an @
% Kludge this until the fonts are right (grr).
\def\@{{\tt \char '100}}

% This is turned off because it was never documented
% and you can use @w{...} around a quote to suppress ligatures.
%% Define @` and @' to be the same as ` and '
%% but suppressing ligatures.
%\def\`{{`}}
%\def\'{{'}}

% Used to generate quoted braces.

\def\mylbrace {{\tt \char '173}}
\def\myrbrace {{\tt \char '175}}
\let\{=\mylbrace
\let\}=\myrbrace

% @: forces normal size whitespace following.
\def\:{\spacefactor=1000 }

% @* forces a line break.
\def\*{\hfil\break\hbox{}\ignorespaces}

% @. is an end-of-sentence period.
\def\.{.\spacefactor=3000 }

% @w prevents a word break.  Without the \leavevmode, @w at the
% beginning of a paragraph, when TeX is still in vertical mode, would
% produce a whole line of output instead of starting the paragraph.
\def\w#1{\leavevmode\hbox{#1}}

% @group ... @end group forces ... to be all on one page, by enclosing
% it in a TeX vbox.  We use \vtop instead of \vbox to construct the box
% to keep its height that of a normal line.  According to the rules for
% \topskip (p.114 of the TeXbook), the glue inserted is
% max (\topskip - \ht (first item), 0).  If that height is large,
% therefore, no glue is inserted, and the space between the headline and
% the text is small, which looks bad.
%
\def\group{\begingroup
  \ifnum\catcode13=\active \else
    \errhelp = \groupinvalidhelp
    \errmessage{@group invalid in context where filling is enabled}%
  \fi
  %
  % The \vtop we start below produces a box with normal height and large
  % depth; thus, TeX puts \baselineskip glue before it, and (when the
  % next line of text is done) \lineskip glue after it.  (See p.82 of
  % the TeXbook.)  Thus, space below is not quite equal to space
  % above.  But it's pretty close.
  \def\Egroup{%
    \egroup           % End the \vtop.
    \endgroup         % End the \group.
  }%
  %
  \vtop\bgroup
    % We have to put a strut on the last line in case the @group is in
    % the midst of an example, rather than completely enclosing it.
    % Otherwise, the interline space between the last line of the group
    % and the first line afterwards is too small.  But we can't put the
    % strut in \Egroup, since there it would be on a line by itself.
    % Hence this just inserts a strut at the beginning of each line.
    \everypar = {\strut}%
    %
    % Since we have a strut on every line, we don't need any of TeX's
    % normal interline spacing.
    \offinterlineskip
    %
    % OK, but now we have to do something about blank
    % lines in the input in @example-like environments, which normally
    % just turn into \lisppar, which will insert no space now that we've
    % turned off the interline space.  Simplest is to make them be an
    % empty paragraph.
    \ifx\par\lisppar
      \edef\par{\leavevmode \par}%
      %
      % Reset ^^M's definition to new definition of \par.
      \obeylines
    \fi
    %
    % Do @comment since we are called inside an environment such as
    % @example, where each end-of-line in the input causes an
    % end-of-line in the output.  We don't want the end-of-line after
    % the `@group' to put extra space in the output.  Since @group
    % should appear on a line by itself (according to the Texinfo
    % manual), we don't worry about eating any user text.
    \comment
}
%
% TeX puts in an \escapechar (i.e., `@') at the beginning of the help
% message, so this ends up printing `@group can only ...'.
%
\newhelp\groupinvalidhelp{%
group can only be used in environments such as @example,^^J%
where each line of input produces a line of output.}

% @need space-in-mils
% forces a page break if there is not space-in-mils remaining.

\newdimen\mil  \mil=0.001in

\def\need{\parsearg\needx}

% Old definition--didn't work.
%\def\needx #1{\par %
%% This method tries to make TeX break the page naturally
%% if the depth of the box does not fit.
%{\baselineskip=0pt%
%\vtop to #1\mil{\vfil}\kern -#1\mil\penalty 10000
%\prevdepth=-1000pt
%}}

\def\needx#1{%
  % Go into vertical mode, so we don't make a big box in the middle of a
  % paragraph.
  \par
  %
  % Don't add any leading before our big empty box, but allow a page
  % break, since the best break might be right here.
  \allowbreak
  \nointerlineskip
  \vtop to #1\mil{\vfil}%
  %
  % TeX does not even consider page breaks if a penalty added to the
  % main vertical list is 10000 or more.  But in order to see if the
  % empty box we just added fits on the page, we must make it consider
  % page breaks.  On the other hand, we don't want to actually break the
  % page after the empty box.  So we use a penalty of 9999.
  %
  % There is an extremely small chance that TeX will actually break the
  % page at this \penalty, if there are no other feasible breakpoints in
  % sight.  (If the user is using lots of big @group commands, which
  % almost-but-not-quite fill up a page, TeX will have a hard time doing
  % good page breaking, for example.)  However, I could not construct an
  % example where a page broke at this \penalty; if it happens in a real
  % document, then we can reconsider our strategy.
  \penalty9999
  %
  % Back up by the size of the box, whether we did a page break or not.
  \kern -#1\mil
  %
  % Do not allow a page break right after this kern.
  \nobreak
}

% @br   forces paragraph break

\let\br = \par

% @dots{}  output some dots

\def\dots{$\ldots$}

% @page    forces the start of a new page

\def\page{\par\vfill\supereject}

% @exdent text....
% outputs text on separate line in roman font, starting at standard page margin

% This records the amount of indent in the innermost environment.
% That's how much \exdent should take out.
\newskip\exdentamount

% This defn is used inside fill environments such as @defun.
\def\exdent{\parsearg\exdentyyy}
\def\exdentyyy #1{{\hfil\break\hbox{\kern -\exdentamount{\rm#1}}\hfil\break}}

% This defn is used inside nofill environments such as @example.
\def\nofillexdent{\parsearg\nofillexdentyyy}
\def\nofillexdentyyy #1{{\advance \leftskip by -\exdentamount
\leftline{\hskip\leftskip{\rm#1}}}}

%\hbox{{\rm#1}}\hfil\break}}

% @include file    insert text of that file as input.

\def\include{\parsearg\includezzz}
%Use \input\thisfile to avoid blank after \input, which may be an active
%char (in which case the blank would become the \input argument).
%The grouping keeps the value of \thisfile correct even when @include
%is nested.
\def\includezzz #1{\begingroup
\def\thisfile{#1}\input\thisfile
\endgroup}

\def\thisfile{}

% @center line   outputs that line, centered

\def\center{\parsearg\centerzzz}
\def\centerzzz #1{{\advance\hsize by -\leftskip
\advance\hsize by -\rightskip
\centerline{#1}}}

% @sp n   outputs n lines of vertical space

\def\sp{\parsearg\spxxx}
\def\spxxx #1{\par \vskip #1\baselineskip}

% @comment ...line which is ignored...
% @c is the same as @comment
% @ignore ... @end ignore  is another way to write a comment

\def\comment{\catcode 64=\other \catcode 123=\other \catcode 125=\other%
\parsearg \commentxxx}

\def\commentxxx #1{\catcode 64=0 \catcode 123=1 \catcode 125=2 }

\let\c=\comment

% Prevent errors for section commands.
% Used in @ignore and in failing conditionals.
\def\ignoresections{%
\let\chapter=\relax
\let\unnumbered=\relax
\let\top=\relax
\let\unnumberedsec=\relax
\let\unnumberedsection=\relax
\let\unnumberedsubsec=\relax
\let\unnumberedsubsection=\relax
\let\unnumberedsubsubsec=\relax
\let\unnumberedsubsubsection=\relax
\let\section=\relax
\let\subsec=\relax
\let\subsubsec=\relax
\let\subsection=\relax
\let\subsubsection=\relax
\let\appendix=\relax
\let\appendixsec=\relax
\let\appendixsection=\relax
\let\appendixsubsec=\relax
\let\appendixsubsection=\relax
\let\appendixsubsubsec=\relax
\let\appendixsubsubsection=\relax
\let\contents=\relax
\let\smallbook=\relax
\let\titlepage=\relax
}

% Used in nested conditionals, where we have to parse the Texinfo source
% and so want to turn off most commands, in case they are used
% incorrectly.
%
\def\ignoremorecommands{%
  \let\defcv = \relax
  \let\deffn = \relax
  \let\deffnx = \relax
  \let\defindex = \relax
  \let\defivar = \relax
  \let\defmac = \relax
  \let\defmethod = \relax
  \let\defop = \relax
  \let\defopt = \relax
  \let\defspec = \relax
  \let\deftp = \relax
  \let\deftypefn = \relax
  \let\deftypefun = \relax
  \let\deftypevar = \relax
  \let\deftypevr = \relax
  \let\defun = \relax
  \let\defvar = \relax
  \let\defvr = \relax
  \let\ref = \relax
  \let\xref = \relax
  \let\printindex = \relax
  \let\pxref = \relax
  \let\settitle = \relax
  \let\include = \relax
  \let\lowersections = \relax
  \let\down = \relax
  \let\raisesections = \relax
  \let\up = \relax
  \let\set = \relax
  \let\clear = \relax
  \let\item = \relax
  \let\message = \relax
}

% Ignore @ignore ... @end ignore.
%
\def\ignore{\doignore{ignore}}

% Also ignore @ifinfo, @menu, and @direntry text.
%
\def\ifinfo{\doignore{ifinfo}}
\def\menu{\doignore{menu}}
\def\direntry{\doignore{direntry}}

% Ignore text until a line `@end #1'.
%
\def\doignore#1{\begingroup
  % Don't complain about control sequences we have declared \outer.
  \ignoresections
  %
  % Define a command to swallow text until we reach `@end #1'.
  \long\def\doignoretext##1\end #1{\enddoignore}%
  %
  % Make sure that spaces turn into tokens that match what \doignoretext wants.
  \catcode32 = 10
  %
  % And now expand that command.
  \doignoretext
}

% What we do to finish off ignored text.
%
\def\enddoignore{\endgroup\ignorespaces}%

\newif\ifwarnedobs\warnedobsfalse
\def\obstexwarn{%
  \ifwarnedobs\relax\else
  % We need to warn folks that they may have trouble with TeX 3.0.
  % This uses \immediate\write16 rather than \message to get newlines.
    \immediate\write16{}
    \immediate\write16{***WARNING*** for users of Unix TeX 3.0!}
    \immediate\write16{This manual trips a bug in TeX version 3.0 (tex hangs).}
    \immediate\write16{If you are running another version of TeX, relax.}
    \immediate\write16{If you are running Unix TeX 3.0, kill this TeX process.}
    \immediate\write16{  Then upgrade your TeX installation if you can.}
    \immediate\write16{If you are stuck with version 3.0, run the}
    \immediate\write16{  script ``tex3patch'' from the Texinfo distribution}
    \immediate\write16{  to use a workaround.}
    \immediate\write16{}
    \warnedobstrue
    \fi
}

% **In TeX 3.0, setting text in \nullfont hangs tex.  For a
% workaround (which requires the file ``dummy.tfm'' to be installed),
% uncomment the following line:
%%%%%\font\nullfont=dummy\let\obstexwarn=\relax

% Ignore text, except that we keep track of conditional commands for
% purposes of nesting, up to an `@end #1' command.
%
\def\nestedignore#1{%
  \obstexwarn
  % We must actually expand the ignored text to look for the @end
  % command, so that nested ignore constructs work.  Thus, we put the
  % text into a \vbox and then do nothing with the result.  To minimize
  % the change of memory overflow, we follow the approach outlined on
  % page 401 of the TeXbook: make the current font be a dummy font.
  %
  \setbox0 = \vbox\bgroup
    % Don't complain about control sequences we have declared \outer.
    \ignoresections
    %
    % Define `@end #1' to end the box, which will in turn undefine the
    % @end command again.
    \expandafter\def\csname E#1\endcsname{\egroup\ignorespaces}%
    %
    % We are going to be parsing Texinfo commands.  Most cause no
    % trouble when they are used incorrectly, but some commands do
    % complicated argument parsing or otherwise get confused, so we
    % undefine them.
    %
    % We can't do anything about stray @-signs, unfortunately;
    % they'll produce `undefined control sequence' errors.
    \ignoremorecommands
    %
    % Set the current font to be \nullfont, a TeX primitive, and define
    % all the font commands to also use \nullfont.  We don't use
    % dummy.tfm, as suggested in the TeXbook, because not all sites
    % might have that installed.  Therefore, math mode will still
    % produce output, but that should be an extremely small amount of
    % stuff compared to the main input.
    %
    \nullfont
    \let\tenrm = \nullfont  \let\tenit = \nullfont  \let\tensl = \nullfont
    \let\tenbf = \nullfont  \let\tentt = \nullfont  \let\smallcaps = \nullfont
    \let\tensf = \nullfont
    % Similarly for index fonts (mostly for their use in
    % smallexample)
    \let\indrm = \nullfont  \let\indit = \nullfont  \let\indsl = \nullfont
    \let\indbf = \nullfont  \let\indtt = \nullfont  \let\indsc = \nullfont
    \let\indsf = \nullfont
    %
    % Don't complain when characters are missing from the fonts.
    \tracinglostchars = 0
    %
    % Don't bother to do space factor calculations.
    \frenchspacing
    %
    % Don't report underfull hboxes.
    \hbadness = 10000
    %
    % Do minimal line-breaking.
    \pretolerance = 10000
    %
    % Do not execute instructions in @tex
    \def\tex{\doignore{tex}}
}

% @set VAR sets the variable VAR to an empty value.
% @set VAR REST-OF-LINE sets VAR to the value REST-OF-LINE.
%
% Since we want to separate VAR from REST-OF-LINE (which might be
% empty), we can't just use \parsearg; we have to insert a space of our
% own to delimit the rest of the line, and then take it out again if we
% didn't need it.
%
\def\set{\parsearg\setxxx}
\def\setxxx#1{\setyyy#1 \endsetyyy}
\def\setyyy#1 #2\endsetyyy{%
  \def\temp{#2}%
  \ifx\temp\empty \global\expandafter\let\csname SET#1\endcsname = \empty
  \else \setzzz{#1}#2\endsetzzz % Remove the trailing space \setxxx inserted.
  \fi
}
\def\setzzz#1#2 \endsetzzz{\expandafter\xdef\csname SET#1\endcsname{#2}}

% @clear VAR clears (i.e., unsets) the variable VAR.
%
\def\clear{\parsearg\clearxxx}
\def\clearxxx#1{\global\expandafter\let\csname SET#1\endcsname=\relax}

% @value{foo} gets the text saved in variable foo.
%
\def\value#1{\expandafter
                \ifx\csname SET#1\endcsname\relax
                        {\{No value for ``#1''\}}
                \else \csname SET#1\endcsname \fi}

% @ifset VAR ... @end ifset reads the `...' iff VAR has been defined
% with @set.
%
\def\ifset{\parsearg\ifsetxxx}
\def\ifsetxxx #1{%
  \expandafter\ifx\csname SET#1\endcsname\relax
    \expandafter\ifsetfail
  \else
    \expandafter\ifsetsucceed
  \fi
}
\def\ifsetsucceed{\conditionalsucceed{ifset}}
\def\ifsetfail{\nestedignore{ifset}}
\defineunmatchedend{ifset}

% @ifclear VAR ... @end ifclear reads the `...' iff VAR has never been
% defined with @set, or has been undefined with @clear.
%
\def\ifclear{\parsearg\ifclearxxx}
\def\ifclearxxx #1{%
  \expandafter\ifx\csname SET#1\endcsname\relax
    \expandafter\ifclearsucceed
  \else
    \expandafter\ifclearfail
  \fi
}
\def\ifclearsucceed{\conditionalsucceed{ifclear}}
\def\ifclearfail{\nestedignore{ifclear}}
\defineunmatchedend{ifclear}

% @iftex always succeeds; we read the text following, through @end
% iftex).  But `@end iftex' should be valid only after an @iftex.
%
\def\iftex{\conditionalsucceed{iftex}}
\defineunmatchedend{iftex}

% We can't just want to start a group at @iftex (for example) and end it
% at @end iftex, since then @set commands inside the conditional have no
% effect (they'd get reverted at the end of the group).  So we must
% define \Eiftex to redefine itself to be its previous value.  (We can't
% just define it to fail again with an ``unmatched end'' error, since
% the @ifset might be nested.)
%
\def\conditionalsucceed#1{%
  \edef\temp{%
    % Remember the current value of \E#1.
    \let\nece{prevE#1} = \nece{E#1}%
    %
    % At the `@end #1', redefine \E#1 to be its previous value.
    \def\nece{E#1}{\let\nece{E#1} = \nece{prevE#1}}%
  }%
  \temp
}

% We need to expand lots of \csname's, but we don't want to expand the
% control sequences after we've constructed them.
%
\def\nece#1{\expandafter\noexpand\csname#1\endcsname}

% @asis just yields its argument.  Used with @table, for example.
%
\def\asis#1{#1}

% @math means output in math mode.
% We don't use $'s directly in the definition of \math because control
% sequences like \math are expanded when the toc file is written.  Then,
% we read the toc file back, the $'s will be normal characters (as they
% should be, according to the definition of Texinfo).  So we must use a
% control sequence to switch into and out of math mode.
%
% This isn't quite enough for @math to work properly in indices, but it
% seems unlikely it will ever be needed there.
%
\let\implicitmath = $
\def\math#1{\implicitmath #1\implicitmath}

% @bullet and @minus need the same treatment as @math, just above.
\def\bullet{\implicitmath\ptexbullet\implicitmath}
\def\minus{\implicitmath-\implicitmath}

\def\node{\ENVcheck\parsearg\nodezzz}
\def\nodezzz#1{\nodexxx [#1,]}
\def\nodexxx[#1,#2]{\gdef\lastnode{#1}}
\let\nwnode=\node
\let\lastnode=\relax

\def\donoderef{\ifx\lastnode\relax\else
\expandafter\expandafter\expandafter\setref{\lastnode}\fi
\let\lastnode=\relax}

\def\unnumbnoderef{\ifx\lastnode\relax\else
\expandafter\expandafter\expandafter\unnumbsetref{\lastnode}\fi
\let\lastnode=\relax}

\def\appendixnoderef{\ifx\lastnode\relax\else
\expandafter\expandafter\expandafter\appendixsetref{\lastnode}\fi
\let\lastnode=\relax}

\let\refill=\relax

% @setfilename is done at the beginning of every texinfo file.
% So open here the files we need to have open while reading the input.
% This makes it possible to make a .fmt file for texinfo.
\def\setfilename{%
   \readauxfile
   \opencontents
   \openindices
   \fixbackslash  % Turn off hack to swallow `\input texinfo'.
   \global\let\setfilename=\comment % Ignore extra @setfilename cmds.
   \comment % Ignore the actual filename.
}

\outer\def\bye{\pagealignmacro\tracingstats=1\ptexend}

\def\inforef #1{\inforefzzz #1,,,,**}
\def\inforefzzz #1,#2,#3,#4**{\putwordSee{} \putwordInfo{} \putwordfile{} \file{\ignorespaces #3{}},
  node \samp{\ignorespaces#1{}}}

\message{fonts,}

% Font-change commands.

% Texinfo supports the sans serif font style, which plain TeX does not.
% So we set up a \sf analogous to plain's \rm, etc.
\newfam\sffam
\def\sf{\fam=\sffam \tensf}
\let\li = \sf % Sometimes we call it \li, not \sf.

%% Try out Computer Modern fonts at \magstephalf
\let\mainmagstep=\magstephalf

\ifx\bigger\relax
\let\mainmagstep=\magstep1
\font\textrm=ptmr7t scaled \magstep 1
\font\texttt=pcrr7t scaled \magstep 1
\else
\font\textrm=ptmr7t scaled \mainmagstep
\font\texttt=pcrr7t scaled \mainmagstep
\fi
% Instead of cmb10, you many want to use cmbx10.
% cmbx10 is a prettier font on its own, but cmb10
% looks better when embedded in a line with cmr10.
\font\textbf=ptmb7t scaled \mainmagstep
\font\textit=ptmri7t scaled \mainmagstep
\font\textsl=ptmro7t scaled \mainmagstep
\font\textsf=phvr7t scaled \mainmagstep
\font\textsc=ptmrc7t scaled \mainmagstep
\font\texti=ptmri7t scaled \mainmagstep
\font\textsy=cmsy10 scaled \mainmagstep

% A few fonts for @defun, etc.
\font\defbf=ptmb7t scaled \magstep1 %was 1314
\font\deftt=pcrr7t scaled \magstep1
\def\df{\let\tentt=\deftt \let\tenbf = \defbf \bf}

% Fonts for indices and small examples.
% We actually use the slanted font rather than the italic,
% because texinfo normally uses the slanted fonts for that.
% Do not make many font distinctions in general in the index, since they
% aren't very useful.
\font\ninett=pcrr7t at 9pt
\font\indrm=ptmr7t at 9pt
\font\indit=ptmri7t at 9pt
\let\indsl=\indit
\let\indtt=\ninett
\let\indsf=\indrm
\let\indbf=\indrm
\let\indsc=\indrm
\font\indi=ptmri7t at 9pt
\font\indsy=cmsy9

% Fonts for headings
\font\chaprm=ptmb7t scaled \magstep3
\font\chapit=ptmri7t scaled \magstep3
\font\chapsl=ptmro7t scaled \magstep3
\font\chaptt=pcrr7t scaled \magstep3
\font\chapsf=phvr7t scaled \magstep3
\let\chapbf=\chaprm
\font\chapsc=ptmrc7t scaled\magstep3
\font\chapi=ptmri7t scaled \magstep3
\font\chapsy=cmsy10 scaled \magstep3

\font\secrm=ptmb7t scaled \magstep2
\font\secit=ptmri7t scaled \magstep2
\font\secsl=ptmro7t scaled \magstep2
\font\sectt=pcrr7t scaled \magstep2
\font\secsf=phvr7t scaled \magstep2
\font\secbf=ptmb7t scaled \magstep2
\font\secsc=ptmrc7t scaled\magstep2
\font\seci=ptmri7t scaled \magstep2
\font\secsy=cmsy10 scaled \magstep2

% \font\ssecrm=cmbx10 scaled \magstep1    % This size an font looked bad.
% \font\ssecit=cmti10 scaled \magstep1    % The letters were too crowded.
% \font\ssecsl=cmsl10 scaled \magstep1
% \font\ssectt=cmtt10 scaled \magstep1
% \font\ssecsf=cmss10 scaled \magstep1

%\font\ssecrm=cmb10 scaled 1315 % Note the use of cmb rather than cmbx.
%\font\ssecit=cmti10 scaled 1315        % Also, the size is a little larger than
%\font\ssecsl=cmsl10 scaled 1315        % being scaled magstep1.
%\font\ssectt=cmtt10 scaled 1315
%\font\ssecsf=cmss10 scaled 1315

%\let\ssecbf=\ssecrm

\font\ssecrm=ptmb7t scaled \magstep1
\font\ssecit=ptmri7t scaled \magstep1
\font\ssecsl=ptmro7t scaled \magstep1
\font\ssectt=pcrr7t scaled \magstep1
\font\ssecsf=phvr7t scaled \magstep1
\font\ssecbf=ptmb7t scaled \magstep1
\font\ssecsc=ptmrc7t scaled \magstep1
\font\sseci=cmmi12 scaled \magstep1
\font\ssecsy=cmsy10 scaled \magstep1
% The smallcaps and symbol fonts should actually be scaled \magstep1.5,
% but that is not a standard magnification.

% Fonts for title page:
\font\titlerm = ptmb7t scaled \magstep4
\let\authorrm = \secrm

% In order for the font changes to affect most math symbols and letters,
% we have to define the \textfont of the standard families.  Since
% texinfo doesn't allow for producing subscripts and superscripts, we
% don't bother to reset \scriptfont and \scriptscriptfont (which would
% also require loading a lot more fonts).
%
\def\resetmathfonts{%
  \textfont0 = \tenrm \textfont1 = \teni \textfont2 = \tensy
  \textfont\itfam = \tenit \textfont\slfam = \tensl \textfont\bffam = \tenbf
  \textfont\ttfam = \tentt \textfont\sffam = \tensf
}


% The font-changing commands redefine the meanings of \tenSTYLE, instead
% of just \STYLE.  We do this so that font changes will continue to work
% in math mode, where it is the current \fam that is relevant in most
% cases, not the current.  Plain TeX does, for example,
% \def\bf{\fam=\bffam \tenbf}  By redefining \tenbf, we obviate the need
% to redefine \bf itself.
\def\textfonts{%
  \let\tenrm=\textrm \let\tenit=\textit \let\tensl=\textsl
  \let\tenbf=\textbf \let\tentt=\texttt \let\smallcaps=\textsc
  \let\tensf=\textsf \let\teni=\texti \let\tensy=\textsy
  \resetmathfonts}
\def\chapfonts{%
  \let\tenrm=\chaprm \let\tenit=\chapit \let\tensl=\chapsl
  \let\tenbf=\chapbf \let\tentt=\chaptt \let\smallcaps=\chapsc
  \let\tensf=\chapsf \let\teni=\chapi \let\tensy=\chapsy
  \resetmathfonts}
\def\secfonts{%
  \let\tenrm=\secrm \let\tenit=\secit \let\tensl=\secsl
  \let\tenbf=\secbf \let\tentt=\sectt \let\smallcaps=\secsc
  \let\tensf=\secsf \let\teni=\seci \let\tensy=\secsy
  \resetmathfonts}
\def\subsecfonts{%
  \let\tenrm=\ssecrm \let\tenit=\ssecit \let\tensl=\ssecsl
  \let\tenbf=\ssecbf \let\tentt=\ssectt \let\smallcaps=\ssecsc
  \let\tensf=\ssecsf \let\teni=\sseci \let\tensy=\ssecsy
  \resetmathfonts}
\def\indexfonts{%
  \let\tenrm=\indrm \let\tenit=\indit \let\tensl=\indsl
  \let\tenbf=\indbf \let\tentt=\indtt \let\smallcaps=\indsc
  \let\tensf=\indsf \let\teni=\indi \let\tensy=\indsy
  \resetmathfonts}

% Set up the default fonts, so we can use them for creating boxes.
%
\textfonts

% Count depth in font-changes, for error checks
\newcount\fontdepth \fontdepth=0

% Fonts for short table of contents.
\font\shortcontrm=cmr12
\font\shortcontbf=cmbx12
\font\shortcontsl=cmsl12

%% Add scribe-like font environments, plus @l for inline lisp (usually sans
%% serif) and @ii for TeX italic

% \smartitalic{ARG} outputs arg in italics, followed by an italic correction
% unless the following character is such as not to need one.
\def\smartitalicx{\ifx\next,\else\ifx\next-\else\ifx\next.\else\/\fi\fi\fi}
\def\smartitalic#1{{\sl #1}\futurelet\next\smartitalicx}

\let\i=\smartitalic
\let\var=\smartitalic
\let\dfn=\smartitalic
\let\emph=\smartitalic
\let\cite=\smartitalic

\def\b#1{{\bf #1}}
\let\strong=\b

% We can't just use \exhyphenpenalty, because that only has effect at
% the end of a paragraph.  Restore normal hyphenation at the end of the
% group within which \nohyphenation is presumably called.
%
\def\nohyphenation{\hyphenchar\font = -1  \aftergroup\restorehyphenation}
\def\restorehyphenation{\hyphenchar\font = `- }

\def\t#1{%
  {\tt \nohyphenation \rawbackslash \frenchspacing #1}%
  \null
}
\let\ttfont = \t
%\def\samp #1{`{\tt \rawbackslash \frenchspacing #1}'\null}
\def\samp #1{`\tclose{#1}'\null}
\def\key #1{{\tt \nohyphenation \uppercase{#1}}\null}
\def\ctrl #1{{\tt \rawbackslash \hat}#1}

\let\file=\samp

% @code is a modification of @t,
% which makes spaces the same size as normal in the surrounding text.
\def\tclose#1{%
  {%
    % Change normal interword space to be same as for the current font.
    \spaceskip = \fontdimen2\font
    %
    % Switch to typewriter.
    \tt
    %
    % But `\ ' produces the large typewriter interword space.
    \def\ {{\spaceskip = 0pt{} }}%
    %
    % Turn off hyphenation.
    \nohyphenation
    %
    \rawbackslash
    \frenchspacing
    #1%
  }%
  \null
}

% We *must* turn on hyphenation at `-' and `_' in \code.
% Otherwise, it is too hard to avoid overful hboxes
% in the Emacs manual, the Library manual, etc.

% Unfortunately, TeX uses one parameter (\hyphenchar) to control
% both hyphenation at - and hyphenation within words.
% We must therefore turn them both off (\tclose does that)
% and arrange explicitly to hyphenate an a dash.
%  -- rms.
{
\catcode`\-=\active
\catcode`\_=\active
\global\def\code{\begingroup \catcode`\-=\active \let-\codedash \catcode`\_=\active \let_\codeunder \codex}
% The following is used by \doprintindex to insure that long function names
% wrap around.  It is necessary for - and _ to be active before the index is
% read from the file, as \entry parses the arguments long before \code is
% ever called.  -- mycroft
\global\def\indexbreaks{\catcode`\-=\active \let-\realdash \catcode`\_=\active \let_\realunder}
}
\def\realdash{-}
\def\realunder{_}
\def\codedash{-\discretionary{}{}{}}
\def\codeunder{\normalunderscore\discretionary{}{}{}}
\def\codex #1{\tclose{#1}\endgroup}

%\let\exp=\tclose  %Was temporary

% @kbd is like @code, except that if the argument is just one @key command,
% then @kbd has no effect.

\def\xkey{\key}
\def\kbdfoo#1#2#3\par{\def\one{#1}\def\three{#3}\def\threex{??}%
\ifx\one\xkey\ifx\threex\three \key{#2}%
\else\tclose{\look}\fi
\else\tclose{\look}\fi}

% Typeset a dimension, e.g., `in' or `pt'.  The only reason for the
% argument is to make the input look right: @dmn{pt} instead of
% @dmn{}pt.
%
\def\dmn#1{\thinspace #1}

\def\kbd#1{\def\look{#1}\expandafter\kbdfoo\look??\par}

\def\l#1{{\li #1}\null}         %

\def\r#1{{\rm #1}}              % roman font
% Use of \lowercase was suggested.
\def\sc#1{{\smallcaps#1}}       % smallcaps font
\def\ii#1{{\it #1}}             % italic font

\message{page headings,}

\newskip\titlepagetopglue \titlepagetopglue = 1.5in
\newskip\titlepagebottomglue \titlepagebottomglue = 2pc

% First the title page.  Must do @settitle before @titlepage.
\def\titlefont#1{{\titlerm #1}}

\newif\ifseenauthor
\newif\iffinishedtitlepage

\def\shorttitlepage{\parsearg\shorttitlepagezzz}
\def\shorttitlepagezzz #1{\begingroup\hbox{}\vskip 1.5in \chaprm \centerline{#1}%
        \endgroup\page\hbox{}\page}

\def\titlepage{\begingroup \parindent=0pt \textfonts
   \let\subtitlerm=\tenrm
% I deinstalled the following change because \cmr12 is undefined.
% This change was not in the ChangeLog anyway.  --rms.
%   \let\subtitlerm=\cmr12
   \def\subtitlefont{\subtitlerm \normalbaselineskip = 13pt \normalbaselines}%
   %
   \def\authorfont{\authorrm \normalbaselineskip = 16pt \normalbaselines}%
   %
   % Leave some space at the very top of the page.
   \vglue\titlepagetopglue
   %
   % Now you can print the title using @title.
   \def\title{\parsearg\titlezzz}%
   \def\titlezzz##1{\leftline{\titlefont{##1}}
                    % print a rule at the page bottom also.
                    \finishedtitlepagefalse
                    \vskip4pt \hrule height 4pt width \hsize \vskip4pt}%
   % No rule at page bottom unless we print one at the top with @title.
   \finishedtitlepagetrue
   %
   % Now you can put text using @subtitle.
   \def\subtitle{\parsearg\subtitlezzz}%
   \def\subtitlezzz##1{{\subtitlefont \rightline{##1}}}%
   %
   % @author should come last, but may come many times.
   \def\author{\parsearg\authorzzz}%
   \def\authorzzz##1{\ifseenauthor\else\vskip 0pt plus 1filll\seenauthortrue\fi
      {\authorfont \leftline{##1}}}%
   %
   % Most title ``pages'' are actually two pages long, with space
   % at the top of the second.  We don't want the ragged left on the second.
   \let\oldpage = \page
   \def\page{%
      \iffinishedtitlepage\else
         \finishtitlepage
      \fi
      \oldpage
      \let\page = \oldpage
      \hbox{}}%
%   \def\page{\oldpage \hbox{}}
}

\def\Etitlepage{%
   \iffinishedtitlepage\else
      \finishtitlepage
   \fi
   % It is important to do the page break before ending the group,
   % because the headline and footline are only empty inside the group.
   % If we use the new definition of \page, we always get a blank page
   % after the title page, which we certainly don't want.
   \oldpage
   \endgroup
   \HEADINGSon
}

\def\finishtitlepage{%
   \vskip4pt \hrule height 2pt width \hsize
   \vskip\titlepagebottomglue
   \finishedtitlepagetrue
}

%%% Set up page headings and footings.

\let\thispage=\folio

\newtoks \evenheadline    % Token sequence for heading line of even pages
\newtoks \oddheadline     % Token sequence for heading line of odd pages
\newtoks \evenfootline    % Token sequence for footing line of even pages
\newtoks \oddfootline     % Token sequence for footing line of odd pages

% Now make Tex use those variables
\headline={{\textfonts\rm \ifodd\pageno \the\oddheadline
                            \else \the\evenheadline \fi}}
\footline={{\textfonts\rm \ifodd\pageno \the\oddfootline
                            \else \the\evenfootline \fi}\HEADINGShook}
\let\HEADINGShook=\relax

% Commands to set those variables.
% For example, this is what  @headings on  does
% @evenheading @thistitle|@thispage|@thischapter
% @oddheading @thischapter|@thispage|@thistitle
% @evenfooting @thisfile||
% @oddfooting ||@thisfile

\def\evenheading{\parsearg\evenheadingxxx}
\def\oddheading{\parsearg\oddheadingxxx}
\def\everyheading{\parsearg\everyheadingxxx}

\def\evenfooting{\parsearg\evenfootingxxx}
\def\oddfooting{\parsearg\oddfootingxxx}
\def\everyfooting{\parsearg\everyfootingxxx}

{\catcode`\@=0 %

\gdef\evenheadingxxx #1{\evenheadingyyy #1@|@|@|@|\finish}
\gdef\evenheadingyyy #1@|#2@|#3@|#4\finish{%
\global\evenheadline={\rlap{\centerline{#2}}\line{#1\hfil#3}}}

\gdef\oddheadingxxx #1{\oddheadingyyy #1@|@|@|@|\finish}
\gdef\oddheadingyyy #1@|#2@|#3@|#4\finish{%
\global\oddheadline={\rlap{\centerline{#2}}\line{#1\hfil#3}}}

\gdef\everyheadingxxx #1{\everyheadingyyy #1@|@|@|@|\finish}
\gdef\everyheadingyyy #1@|#2@|#3@|#4\finish{%
\global\evenheadline={\rlap{\centerline{#2}}\line{#1\hfil#3}}
\global\oddheadline={\rlap{\centerline{#2}}\line{#1\hfil#3}}}

\gdef\evenfootingxxx #1{\evenfootingyyy #1@|@|@|@|\finish}
\gdef\evenfootingyyy #1@|#2@|#3@|#4\finish{%
\global\evenfootline={\rlap{\centerline{#2}}\line{#1\hfil#3}}}

\gdef\oddfootingxxx #1{\oddfootingyyy #1@|@|@|@|\finish}
\gdef\oddfootingyyy #1@|#2@|#3@|#4\finish{%
\global\oddfootline={\rlap{\centerline{#2}}\line{#1\hfil#3}}}

\gdef\everyfootingxxx #1{\everyfootingyyy #1@|@|@|@|\finish}
\gdef\everyfootingyyy #1@|#2@|#3@|#4\finish{%
\global\evenfootline={\rlap{\centerline{#2}}\line{#1\hfil#3}}
\global\oddfootline={\rlap{\centerline{#2}}\line{#1\hfil#3}}}
%
}% unbind the catcode of @.

% @headings double      turns headings on for double-sided printing.
% @headings single      turns headings on for single-sided printing.
% @headings off         turns them off.
% @headings on          same as @headings double, retained for compatibility.
% @headings after       turns on double-sided headings after this page.
% @headings doubleafter turns on double-sided headings after this page.
% @headings singleafter turns on single-sided headings after this page.
% By default, they are off.

\def\headings #1 {\csname HEADINGS#1\endcsname}

\def\HEADINGSoff{
\global\evenheadline={\hfil} \global\evenfootline={\hfil}
\global\oddheadline={\hfil} \global\oddfootline={\hfil}}
\HEADINGSoff
% When we turn headings on, set the page number to 1.
% For double-sided printing, put current file name in lower left corner,
% chapter name on inside top of right hand pages, document
% title on inside top of left hand pages, and page numbers on outside top
% edge of all pages.
\def\HEADINGSdouble{
%\pagealignmacro
\global\pageno=1
\global\evenfootline={\hfil}
\global\oddfootline={\hfil}
\global\evenheadline={\line{\folio\hfil\thistitle}}
\global\oddheadline={\line{\thischapter\hfil\folio}}
}
% For single-sided printing, chapter title goes across top left of page,
% page number on top right.
\def\HEADINGSsingle{
%\pagealignmacro
\global\pageno=1
\global\evenfootline={\hfil}
\global\oddfootline={\hfil}
\global\evenheadline={\line{\thischapter\hfil\folio}}
\global\oddheadline={\line{\thischapter\hfil\folio}}
}
\def\HEADINGSon{\HEADINGSdouble}

\def\HEADINGSafter{\let\HEADINGShook=\HEADINGSdoublex}
\let\HEADINGSdoubleafter=\HEADINGSafter
\def\HEADINGSdoublex{%
\global\evenfootline={\hfil}
\global\oddfootline={\hfil}
\global\evenheadline={\line{\folio\hfil\thistitle}}
\global\oddheadline={\line{\thischapter\hfil\folio}}
}

\def\HEADINGSsingleafter{\let\HEADINGShook=\HEADINGSsinglex}
\def\HEADINGSsinglex{%
\global\evenfootline={\hfil}
\global\oddfootline={\hfil}
\global\evenheadline={\line{\thischapter\hfil\folio}}
\global\oddheadline={\line{\thischapter\hfil\folio}}
}

% Subroutines used in generating headings
% Produces Day Month Year style of output.
\def\today{\number\day\space
\ifcase\month\or
January\or February\or March\or April\or May\or June\or
July\or August\or September\or October\or November\or December\fi
\space\number\year}

% Use this if you want the Month Day, Year style of output.
%\def\today{\ifcase\month\or
%January\or February\or March\or April\or May\or June\or
%July\or August\or September\or October\or November\or December\fi
%\space\number\day, \number\year}

% @settitle line...  specifies the title of the document, for headings
% It generates no output of its own

\def\thistitle{No Title}
\def\settitle{\parsearg\settitlezzz}
\def\settitlezzz #1{\gdef\thistitle{#1}}

\message{tables,}

% @tabs -- simple alignment

% These don't work.  For one thing, \+ is defined as outer.
% So these macros cannot even be defined.

%\def\tabs{\parsearg\tabszzz}
%\def\tabszzz #1{\settabs\+#1\cr}
%\def\tabline{\parsearg\tablinezzz}
%\def\tablinezzz #1{\+#1\cr}
%\def\&{&}

% Tables -- @table, @ftable, @vtable, @item(x), @kitem(x), @xitem(x).

% default indentation of table text
\newdimen\tableindent \tableindent=.8in
% default indentation of @itemize and @enumerate text
\newdimen\itemindent  \itemindent=.3in
% margin between end of table item and start of table text.
\newdimen\itemmargin  \itemmargin=.1in

% used internally for \itemindent minus \itemmargin
\newdimen\itemmax

% Note @table, @vtable, and @vtable define @item, @itemx, etc., with
% these defs.
% They also define \itemindex
% to index the item name in whatever manner is desired (perhaps none).

\newif\ifitemxneedsnegativevskip

\def\itemxpar{\par\ifitemxneedsnegativevskip\vskip-\parskip\nobreak\fi}

\def\internalBitem{\smallbreak \parsearg\itemzzz}
\def\internalBitemx{\itemxpar \parsearg\itemzzz}

\def\internalBxitem "#1"{\def\xitemsubtopix{#1} \smallbreak \parsearg\xitemzzz}
\def\internalBxitemx "#1"{\def\xitemsubtopix{#1} \itemxpar \parsearg\xitemzzz}

\def\internalBkitem{\smallbreak \parsearg\kitemzzz}
\def\internalBkitemx{\itemxpar \parsearg\kitemzzz}

\def\kitemzzz #1{\dosubind {kw}{\code{#1}}{for {\bf \lastfunction}}%
                 \itemzzz {#1}}

\def\xitemzzz #1{\dosubind {kw}{\code{#1}}{for {\bf \xitemsubtopic}}%
                 \itemzzz {#1}}

\def\itemzzz #1{\begingroup %
  \advance\hsize by -\rightskip
  \advance\hsize by -\tableindent
  \setbox0=\hbox{\itemfont{#1}}%
  \itemindex{#1}%
  \nobreak % This prevents a break before @itemx.
  %
  % Be sure we are not still in the middle of a paragraph.
  %{\parskip = 0in
  %\par
  %}%
  %
  % If the item text does not fit in the space we have, put it on a line
  % by itself, and do not allow a page break either before or after that
  % line.  We do not start a paragraph here because then if the next
  % command is, e.g., @kindex, the whatsit would get put into the
  % horizontal list on a line by itself, resulting in extra blank space.
  \ifdim \wd0>\itemmax
    %
    % Make this a paragraph so we get the \parskip glue and wrapping,
    % but leave it ragged-right.
    \begingroup
      \advance\leftskip by-\tableindent
      \advance\hsize by\tableindent
      \advance\rightskip by0pt plus1fil
      \leavevmode\unhbox0\par
    \endgroup
    %
    % We're going to be starting a paragraph, but we don't want the
    % \parskip glue -- logically it's part of the @item we just started.
    \nobreak \vskip-\parskip
    %
    % Stop a page break at the \parskip glue coming up.  Unfortunately
    % we can't prevent a possible page break at the following
    % \baselineskip glue.
    \nobreak
    \endgroup
    \itemxneedsnegativevskipfalse
  \else
    % The item text fits into the space.  Start a paragraph, so that the
    % following text (if any) will end up on the same line.  Since that
    % text will be indented by \tableindent, we make the item text be in
    % a zero-width box.
    \noindent
    \rlap{\hskip -\tableindent\box0}\ignorespaces%
    \endgroup%
    \itemxneedsnegativevskiptrue%
  \fi
}

\def\item{\errmessage{@item while not in a table}}
\def\itemx{\errmessage{@itemx while not in a table}}
\def\kitem{\errmessage{@kitem while not in a table}}
\def\kitemx{\errmessage{@kitemx while not in a table}}
\def\xitem{\errmessage{@xitem while not in a table}}
\def\xitemx{\errmessage{@xitemx while not in a table}}

%% Contains a kludge to get @end[description] to work
\def\description{\tablez{\dontindex}{1}{}{}{}{}}

\def\table{\begingroup\inENV\obeylines\obeyspaces\tablex}
{\obeylines\obeyspaces%
\gdef\tablex #1^^M{%
\tabley\dontindex#1        \endtabley}}

\def\ftable{\begingroup\inENV\obeylines\obeyspaces\ftablex}
{\obeylines\obeyspaces%
\gdef\ftablex #1^^M{%
\tabley\fnitemindex#1        \endtabley
\def\Eftable{\endgraf\afterenvbreak\endgroup}%
\let\Etable=\relax}}

\def\vtable{\begingroup\inENV\obeylines\obeyspaces\vtablex}
{\obeylines\obeyspaces%
\gdef\vtablex #1^^M{%
\tabley\vritemindex#1        \endtabley
\def\Evtable{\endgraf\afterenvbreak\endgroup}%
\let\Etable=\relax}}

\def\dontindex #1{}
\def\fnitemindex #1{\doind {fn}{\code{#1}}}%
\def\vritemindex #1{\doind {vr}{\code{#1}}}%

{\obeyspaces %
\gdef\tabley#1#2 #3 #4 #5 #6 #7\endtabley{\endgroup%
\tablez{#1}{#2}{#3}{#4}{#5}{#6}}}

\def\tablez #1#2#3#4#5#6{%
\aboveenvbreak %
\begingroup %
\def\Edescription{\Etable}% Neccessary kludge.
\let\itemindex=#1%
\ifnum 0#3>0 \advance \leftskip by #3\mil \fi %
\ifnum 0#4>0 \tableindent=#4\mil \fi %
\ifnum 0#5>0 \advance \rightskip by #5\mil \fi %
\def\itemfont{#2}%
\itemmax=\tableindent %
\advance \itemmax by -\itemmargin %
\advance \leftskip by \tableindent %
\exdentamount=\tableindent
\parindent = 0pt
\parskip = \smallskipamount
\ifdim \parskip=0pt \parskip=2pt \fi%
\def\Etable{\endgraf\afterenvbreak\endgroup}%
\let\item = \internalBitem %
\let\itemx = \internalBitemx %
\let\kitem = \internalBkitem %
\let\kitemx = \internalBkitemx %
\let\xitem = \internalBxitem %
\let\xitemx = \internalBxitemx %
}

% This is the counter used by @enumerate, which is really @itemize

\newcount \itemno

\def\itemize{\parsearg\itemizezzz}

\def\itemizezzz #1{%
  \begingroup % ended by the @end itemsize
  \itemizey {#1}{\Eitemize}
}

\def\itemizey #1#2{%
\aboveenvbreak %
\itemmax=\itemindent %
\advance \itemmax by -\itemmargin %
\advance \leftskip by \itemindent %
\exdentamount=\itemindent
\parindent = 0pt %
\parskip = \smallskipamount %
\ifdim \parskip=0pt \parskip=2pt \fi%
\def#2{\endgraf\afterenvbreak\endgroup}%
\def\itemcontents{#1}%
\let\item=\itemizeitem}

% Set sfcode to normal for the chars that usually have another value.
% These are `.?!:;,'
\def\frenchspacing{\sfcode46=1000 \sfcode63=1000 \sfcode33=1000
  \sfcode58=1000 \sfcode59=1000 \sfcode44=1000 }

% \splitoff TOKENS\endmark defines \first to be the first token in
% TOKENS, and \rest to be the remainder.
%
\def\splitoff#1#2\endmark{\def\first{#1}\def\rest{#2}}%

% Allow an optional argument of an uppercase letter, lowercase letter,
% or number, to specify the first label in the enumerated list.  No
% argument is the same as `1'.
%
\def\enumerate{\parsearg\enumeratezzz}
\def\enumeratezzz #1{\enumeratey #1  \endenumeratey}
\def\enumeratey #1 #2\endenumeratey{%
  \begingroup % ended by the @end enumerate
  %
  % If we were given no argument, pretend we were given `1'.
  \def\thearg{#1}%
  \ifx\thearg\empty \def\thearg{1}\fi
  %
  % Detect if the argument is a single token.  If so, it might be a
  % letter.  Otherwise, the only valid thing it can be is a number.
  % (We will always have one token, because of the test we just made.
  % This is a good thing, since \splitoff doesn't work given nothing at
  % all -- the first parameter is undelimited.)
  \expandafter\splitoff\thearg\endmark
  \ifx\rest\empty
    % Only one token in the argument.  It could still be anything.
    % A ``lowercase letter'' is one whose \lccode is nonzero.
    % An ``uppercase letter'' is one whose \lccode is both nonzero, and
    %   not equal to itself.
    % Otherwise, we assume it's a number.
    %
    % We need the \relax at the end of the \ifnum lines to stop TeX from
    % continuing to look for a <number>.
    %
    \ifnum\lccode\expandafter`\thearg=0\relax
      \numericenumerate % a number (we hope)
    \else
      % It's a letter.
      \ifnum\lccode\expandafter`\thearg=\expandafter`\thearg\relax
        \lowercaseenumerate % lowercase letter
      \else
        \uppercaseenumerate % uppercase letter
      \fi
    \fi
  \else
    % Multiple tokens in the argument.  We hope it's a number.
    \numericenumerate
  \fi
}

% An @enumerate whose labels are integers.  The starting integer is
% given in \thearg.
%
\def\numericenumerate{%
  \itemno = \thearg
  \startenumeration{\the\itemno}%
}

% The starting (lowercase) letter is in \thearg.
\def\lowercaseenumerate{%
  \itemno = \expandafter`\thearg
  \startenumeration{%
    % Be sure we're not beyond the end of the alphabet.
    \ifnum\itemno=0
      \errmessage{No more lowercase letters in @enumerate; get a bigger
                  alphabet}%
    \fi
    \char\lccode\itemno
  }%
}

% The starting (uppercase) letter is in \thearg.
\def\uppercaseenumerate{%
  \itemno = \expandafter`\thearg
  \startenumeration{%
    % Be sure we're not beyond the end of the alphabet.
    \ifnum\itemno=0
      \errmessage{No more uppercase letters in @enumerate; get a bigger
                  alphabet}
    \fi
    \char\uccode\itemno
  }%
}

% Call itemizey, adding a period to the first argument and supplying the
% common last two arguments.  Also subtract one from the initial value in
% \itemno, since @item increments \itemno.
%
\def\startenumeration#1{%
  \advance\itemno by -1
  \itemizey{#1.}\Eenumerate\flushcr
}

% @alphaenumerate and @capsenumerate are abbreviations for giving an arg
% to @enumerate.
%
\def\alphaenumerate{\enumerate{a}}
\def\capsenumerate{\enumerate{A}}
\def\Ealphaenumerate{\Eenumerate}
\def\Ecapsenumerate{\Eenumerate}

% Definition of @item while inside @itemize.

\def\itemizeitem{%
\advance\itemno by 1
{\let\par=\endgraf \smallbreak}%
\ifhmode \errmessage{\in hmode at itemizeitem}\fi
{\parskip=0in \hskip 0pt
\hbox to 0pt{\hss \itemcontents\hskip \itemmargin}%
\vadjust{\penalty 1200}}%
\flushcr}

\message{indexing,}
% Index generation facilities

% Define \newwrite to be identical to plain tex's \newwrite
% except not \outer, so it can be used within \newindex.
{\catcode`\@=11
\gdef\newwrite{\alloc@7\write\chardef\sixt@@n}}

% \newindex {foo} defines an index named foo.
% It automatically defines \fooindex such that
% \fooindex ...rest of line... puts an entry in the index foo.
% It also defines \fooindfile to be the number of the output channel for
% the file that accumulates this index.  The file's extension is foo.
% The name of an index should be no more than 2 characters long
% for the sake of vms.

\def\newindex #1{
\expandafter\newwrite \csname#1indfile\endcsname% Define number for output file
\openout \csname#1indfile\endcsname \jobname.#1 % Open the file
\expandafter\xdef\csname#1index\endcsname{%     % Define \xxxindex
\noexpand\doindex {#1}}
}

% @defindex foo  ==  \newindex{foo}

\def\defindex{\parsearg\newindex}

% Define @defcodeindex, like @defindex except put all entries in @code.

\def\newcodeindex #1{
\expandafter\newwrite \csname#1indfile\endcsname% Define number for output file
\openout \csname#1indfile\endcsname \jobname.#1 % Open the file
\expandafter\xdef\csname#1index\endcsname{%     % Define \xxxindex
\noexpand\docodeindex {#1}}
}

\def\defcodeindex{\parsearg\newcodeindex}

% @synindex foo bar    makes index foo feed into index bar.
% Do this instead of @defindex foo if you don't want it as a separate index.
\def\synindex #1 #2 {%
\expandafter\let\expandafter\synindexfoo\expandafter=\csname#2indfile\endcsname
\expandafter\let\csname#1indfile\endcsname=\synindexfoo
\expandafter\xdef\csname#1index\endcsname{%     % Define \xxxindex
\noexpand\doindex {#2}}%
}

% @syncodeindex foo bar   similar, but put all entries made for index foo
% inside @code.
\def\syncodeindex #1 #2 {%
\expandafter\let\expandafter\synindexfoo\expandafter=\csname#2indfile\endcsname
\expandafter\let\csname#1indfile\endcsname=\synindexfoo
\expandafter\xdef\csname#1index\endcsname{%     % Define \xxxindex
\noexpand\docodeindex {#2}}%
}

% Define \doindex, the driver for all \fooindex macros.
% Argument #1 is generated by the calling \fooindex macro,
%  and it is "foo", the name of the index.

% \doindex just uses \parsearg; it calls \doind for the actual work.
% This is because \doind is more useful to call from other macros.

% There is also \dosubind {index}{topic}{subtopic}
% which makes an entry in a two-level index such as the operation index.

\def\doindex#1{\edef\indexname{#1}\parsearg\singleindexer}
\def\singleindexer #1{\doind{\indexname}{#1}}

% like the previous two, but they put @code around the argument.
\def\docodeindex#1{\edef\indexname{#1}\parsearg\singlecodeindexer}
\def\singlecodeindexer #1{\doind{\indexname}{\code{#1}}}

\def\indexdummies{%
% Take care of the plain tex accent commands.
\def\"{\realbackslash "}%
\def\`{\realbackslash `}%
\def\'{\realbackslash '}%
\def\^{\realbackslash ^}%
\def\~{\realbackslash ~}%
\def\={\realbackslash =}%
\def\b{\realbackslash b}%
\def\c{\realbackslash c}%
\def\d{\realbackslash d}%
\def\u{\realbackslash u}%
\def\v{\realbackslash v}%
\def\H{\realbackslash H}%
% Take care of the plain tex special European modified letters.
\def\oe{\realbackslash oe}%
\def\ae{\realbackslash ae}%
\def\aa{\realbackslash aa}%
\def\OE{\realbackslash OE}%
\def\AE{\realbackslash AE}%
\def\AA{\realbackslash AA}%
\def\o{\realbackslash o}%
\def\O{\realbackslash O}%
\def\l{\realbackslash l}%
\def\L{\realbackslash L}%
\def\ss{\realbackslash ss}%
% Take care of texinfo commands likely to appear in an index entry.
\def\_{{\realbackslash _}}%
\def\w{\realbackslash w }%
\def\bf{\realbackslash bf }%
\def\rm{\realbackslash rm }%
\def\sl{\realbackslash sl }%
\def\sf{\realbackslash sf}%
\def\tt{\realbackslash tt}%
\def\gtr{\realbackslash gtr}%
\def\less{\realbackslash less}%
\def\hat{\realbackslash hat}%
\def\char{\realbackslash char}%
\def\TeX{\realbackslash TeX}%
\def\dots{\realbackslash dots }%
\def\copyright{\realbackslash copyright }%
\def\tclose##1{\realbackslash tclose {##1}}%
\def\code##1{\realbackslash code {##1}}%
\def\samp##1{\realbackslash samp {##1}}%
\def\t##1{\realbackslash r {##1}}%
\def\r##1{\realbackslash r {##1}}%
\def\i##1{\realbackslash i {##1}}%
\def\b##1{\realbackslash b {##1}}%
\def\cite##1{\realbackslash cite {##1}}%
\def\key##1{\realbackslash key {##1}}%
\def\file##1{\realbackslash file {##1}}%
\def\var##1{\realbackslash var {##1}}%
\def\kbd##1{\realbackslash kbd {##1}}%
\def\dfn##1{\realbackslash dfn {##1}}%
\def\emph##1{\realbackslash emph {##1}}%
}

% \indexnofonts no-ops all font-change commands.
% This is used when outputting the strings to sort the index by.
\def\indexdummyfont#1{#1}
\def\indexdummytex{TeX}
\def\indexdummydots{...}

\def\indexnofonts{%
% Just ignore accents.
\let\"=\indexdummyfont
\let\`=\indexdummyfont
\let\'=\indexdummyfont
\let\^=\indexdummyfont
\let\~=\indexdummyfont
\let\==\indexdummyfont
\let\b=\indexdummyfont
\let\c=\indexdummyfont
\let\d=\indexdummyfont
\let\u=\indexdummyfont
\let\v=\indexdummyfont
\let\H=\indexdummyfont
% Take care of the plain tex special European modified letters.
\def\oe{oe}%
\def\ae{ae}%
\def\aa{aa}%
\def\OE{OE}%
\def\AE{AE}%
\def\AA{AA}%
\def\o{o}%
\def\O{O}%
\def\l{l}%
\def\L{L}%
\def\ss{ss}%
\let\w=\indexdummyfont
\let\t=\indexdummyfont
\let\r=\indexdummyfont
\let\i=\indexdummyfont
\let\b=\indexdummyfont
\let\emph=\indexdummyfont
\let\strong=\indexdummyfont
\let\cite=\indexdummyfont
\let\sc=\indexdummyfont
%Don't no-op \tt, since it isn't a user-level command
% and is used in the definitions of the active chars like <, >, |...
%\let\tt=\indexdummyfont
\let\tclose=\indexdummyfont
\let\code=\indexdummyfont
\let\file=\indexdummyfont
\let\samp=\indexdummyfont
\let\kbd=\indexdummyfont
\let\key=\indexdummyfont
\let\var=\indexdummyfont
\let\TeX=\indexdummytex
\let\dots=\indexdummydots
}

% To define \realbackslash, we must make \ not be an escape.
% We must first make another character (@) an escape
% so we do not become unable to do a definition.

{\catcode`\@=0 \catcode`\\=\other
@gdef@realbackslash{\}}

\let\indexbackslash=0  %overridden during \printindex.

\def\doind #1#2{%
{\count10=\lastpenalty %
{\indexdummies % Must do this here, since \bf, etc expand at this stage
\escapechar=`\\%
{\let\folio=0% Expand all macros now EXCEPT \folio
\def\rawbackslashxx{\indexbackslash}% \indexbackslash isn't defined now
% so it will be output as is; and it will print as backslash in the indx.
%
% Now process the index-string once, with all font commands turned off,
% to get the string to sort the index by.
{\indexnofonts
\xdef\temp1{#2}%
}%
% Now produce the complete index entry.  We process the index-string again,
% this time with font commands expanded, to get what to print in the index.
\edef\temp{%
\write \csname#1indfile\endcsname{%
\realbackslash entry {\temp1}{\folio}{#2}}}%
\temp }%
}\penalty\count10}}

\def\dosubind #1#2#3{%
{\count10=\lastpenalty %
{\indexdummies % Must do this here, since \bf, etc expand at this stage
\escapechar=`\\%
{\let\folio=0%
\def\rawbackslashxx{\indexbackslash}%
%
% Now process the index-string once, with all font commands turned off,
% to get the string to sort the index by.
{\indexnofonts
\xdef\temp1{#2 #3}%
}%
% Now produce the complete index entry.  We process the index-string again,
% this time with font commands expanded, to get what to print in the index.
\edef\temp{%
\write \csname#1indfile\endcsname{%
\realbackslash entry {\temp1}{\folio}{#2}{#3}}}%
\temp }%
}\penalty\count10}}

% The index entry written in the file actually looks like
%  \entry {sortstring}{page}{topic}
% or
%  \entry {sortstring}{page}{topic}{subtopic}
% The texindex program reads in these files and writes files
% containing these kinds of lines:
%  \initial {c}
%     before the first topic whose initial is c
%  \entry {topic}{pagelist}
%     for a topic that is used without subtopics
%  \primary {topic}
%     for the beginning of a topic that is used with subtopics
%  \secondary {subtopic}{pagelist}
%     for each subtopic.

% Define the user-accessible indexing commands
% @findex, @vindex, @kindex, @cindex.

\def\findex {\fnindex}
\def\kindex {\kyindex}
\def\cindex {\cpindex}
\def\vindex {\vrindex}
\def\tindex {\tpindex}
\def\pindex {\pgindex}

\def\cindexsub {\begingroup\obeylines\cindexsub}
{\obeylines %
\gdef\cindexsub "#1" #2^^M{\endgroup %
\dosubind{cp}{#2}{#1}}}

% Define the macros used in formatting output of the sorted index material.

% This is what you call to cause a particular index to get printed.
% Write
% @unnumbered Function Index
% @printindex fn

\def\printindex{\parsearg\doprintindex}

\def\doprintindex#1{%
  \tex
  \dobreak \chapheadingskip {10000}
  \catcode`\%=\other\catcode`\&=\other\catcode`\#=\other
  \catcode`\$=\other
  \catcode`\~=\other
  \indexbreaks
  %
  % The following don't help, since the chars were translated
  % when the raw index was written, and their fonts were discarded
  % due to \indexnofonts.
  %\catcode`\"=\active
  %\catcode`\^=\active
  %\catcode`\_=\active
  %\catcode`\|=\active
  %\catcode`\<=\active
  %\catcode`\>=\active
  % %
  \def\indexbackslash{\rawbackslashxx}
  \indexfonts\rm \tolerance=9500 \advance\baselineskip -1pt
  \begindoublecolumns
  %
  % See if the index file exists and is nonempty.
  \openin 1 \jobname.#1s
  \ifeof 1
    % \enddoublecolumns gets confused if there is no text in the index,
    % and it loses the chapter title and the aux file entries for the
    % index.  The easiest way to prevent this problem is to make sure
    % there is some text.
    (Index is nonexistent)
    \else
    %
    % If the index file exists but is empty, then \openin leaves \ifeof
    % false.  We have to make TeX try to read something from the file, so
    % it can discover if there is anything in it.
    \read 1 to \temp
    \ifeof 1
      (Index is empty)
    \else
      \input \jobname.#1s
    \fi
  \fi
  \closein 1
  \enddoublecolumns
  \Etex
}

% These macros are used by the sorted index file itself.
% Change them to control the appearance of the index.

% Same as \bigskipamount except no shrink.
% \balancecolumns gets confused if there is any shrink.
\newskip\initialskipamount \initialskipamount 12pt plus4pt

\def\initial #1{%
{\let\tentt=\sectt \let\tt=\sectt \let\sf=\sectt
\ifdim\lastskip<\initialskipamount
\removelastskip \penalty-200 \vskip \initialskipamount\fi
\line{\secbf#1\hfill}\kern 2pt\penalty10000}}

% This typesets a paragraph consisting of #1, dot leaders, and then #2
% flush to the right margin.  It is used for index and table of contents
% entries.  The paragraph is indented by \leftskip.
%
\def\entry #1#2{\begingroup
  %
  % Start a new paragraph if necessary, so our assignments below can't
  % affect previous text.
  \par
  %
  % Do not fill out the last line with white space.
  \parfillskip = 0in
  %
  % No extra space above this paragraph.
  \parskip = 0in
  %
  % Do not prefer a separate line ending with a hyphen to fewer lines.
  \finalhyphendemerits = 0
  %
  % \hangindent is only relevant when the entry text and page number
  % don't both fit on one line.  In that case, bob suggests starting the
  % dots pretty far over on the line.  Unfortunately, a large
  % indentation looks wrong when the entry text itself is broken across
  % lines.  So we use a small indentation and put up with long leaders.
  %
  % \hangafter is reset to 1 (which is the value we want) at the start
  % of each paragraph, so we need not do anything with that.
  \hangindent=2em
  %
  % When the entry text needs to be broken, just fill out the first line
  % with blank space.
  \rightskip = 0pt plus1fil
  %
  % Start a ``paragraph'' for the index entry so the line breaking
  % parameters we've set above will have an effect.
  \noindent
  %
  % Insert the text of the index entry.  TeX will do line-breaking on it.
  #1%
  % The following is kluged to not output a line of dots in the index if
  % there are no page numbers.  The next person who breaks this will be
  % cursed by a Unix daemon.
  \def\tempa{{\rm }}%
  \def\tempb{#2}%
  \edef\tempc{\tempa}%
  \edef\tempd{\tempb}%
  \ifx\tempc\tempd\ \else%
    %
    % If we must, put the page number on a line of its own, and fill out
    % this line with blank space.  (The \hfil is overwhelmed with the
    % fill leaders glue in \indexdotfill if the page number does fit.)
    \hfil\penalty50
    \null\nobreak\indexdotfill % Have leaders before the page number.
    %
    % The `\ ' here is removed by the implicit \unskip that TeX does as
    % part of (the primitive) \par.  Without it, a spurious underfull
    % \hbox ensues.
    \ #2% The page number ends the paragraph.
  \fi%
  \par
\endgroup}

% Like \dotfill except takes at least 1 em.
\def\indexdotfill{\cleaders
  \hbox{$\mathsurround=0pt \mkern1.5mu ${\it .}$ \mkern1.5mu$}\hskip 1em plus 1fill}

\def\primary #1{\line{#1\hfil}}

\newskip\secondaryindent \secondaryindent=0.5cm

\def\secondary #1#2{
{\parfillskip=0in \parskip=0in
\hangindent =1in \hangafter=1
\noindent\hskip\secondaryindent\hbox{#1}\indexdotfill #2\par
}}

%% Define two-column mode, which is used in indexes.
%% Adapted from the TeXbook, page 416.
\catcode `\@=11

\newbox\partialpage

\newdimen\doublecolumnhsize

\def\begindoublecolumns{\begingroup
  % Grab any single-column material above us.
  \output = {\global\setbox\partialpage
    =\vbox{\unvbox255\kern -\topskip \kern \baselineskip}}%
  \eject
  %
  % Now switch to the double-column output routine.
  \output={\doublecolumnout}%
  %
  % Change the page size parameters.  We could do this once outside this
  % routine, in each of @smallbook, @afourpaper, and the default 8.5x11
  % format, but then we repeat the same computation.  Repeating a couple
  % of assignments once per index is clearly meaningless for the
  % execution time, so we may as well do it once.
  %
  % First we halve the line length, less a little for the gutter between
  % the columns.  We compute the gutter based on the line length, so it
  % changes automatically with the paper format.  The magic constant
  % below is chosen so that the gutter has the same value (well, +- <
  % 1pt) as it did when we hard-coded it.
  %
  % We put the result in a separate register, \doublecolumhsize, so we
  % can restore it in \pagesofar, after \hsize itself has (potentially)
  % been clobbered.
  %
  \doublecolumnhsize = \hsize
    \advance\doublecolumnhsize by -.04154\hsize
    \divide\doublecolumnhsize by 2
  \hsize = \doublecolumnhsize
  %
  % Double the \vsize as well.  (We don't need a separate register here,
  % since nobody clobbers \vsize.)
  \vsize = 2\vsize
  \doublecolumnpagegoal
}

\def\enddoublecolumns{\eject \endgroup \pagegoal=\vsize \unvbox\partialpage}

\def\doublecolumnsplit{\splittopskip=\topskip \splitmaxdepth=\maxdepth
  \global\dimen@=\pageheight \global\advance\dimen@ by-\ht\partialpage
  \global\setbox1=\vsplit255 to\dimen@ \global\setbox0=\vbox{\unvbox1}
  \global\setbox3=\vsplit255 to\dimen@ \global\setbox2=\vbox{\unvbox3}
  \ifdim\ht0>\dimen@ \setbox255=\vbox{\unvbox0\unvbox2} \global\setbox255=\copy5 \fi
  \ifdim\ht2>\dimen@ \setbox255=\vbox{\unvbox0\unvbox2} \global\setbox255=\copy5 \fi
}
\def\doublecolumnpagegoal{%
  \dimen@=\vsize \advance\dimen@ by-2\ht\partialpage \global\pagegoal=\dimen@
}
\def\pagesofar{\unvbox\partialpage %
  \hsize=\doublecolumnhsize % have to restore this since output routine
  \wd0=\hsize \wd2=\hsize \hbox to\pagewidth{\box0\hfil\box2}}
\def\doublecolumnout{%
  \setbox5=\copy255
  {\vbadness=10000 \doublecolumnsplit}
  \ifvbox255
    \setbox0=\vtop to\dimen@{\unvbox0}
    \setbox2=\vtop to\dimen@{\unvbox2}
    \onepageout\pagesofar \unvbox255 \penalty\outputpenalty
  \else
    \setbox0=\vbox{\unvbox5}
    \ifvbox0
      \dimen@=\ht0 \advance\dimen@ by\topskip \advance\dimen@ by-\baselineskip
      \divide\dimen@ by2 \splittopskip=\topskip \splitmaxdepth=\maxdepth
      {\vbadness=10000
        \loop \global\setbox5=\copy0
          \setbox1=\vsplit5 to\dimen@
          \setbox3=\vsplit5 to\dimen@
          \ifvbox5 \global\advance\dimen@ by1pt \repeat
        \setbox0=\vbox to\dimen@{\unvbox1}
        \setbox2=\vbox to\dimen@{\unvbox3}
        \global\setbox\partialpage=\vbox{\pagesofar}
        \doublecolumnpagegoal
      }
    \fi
  \fi
}

\catcode `\@=\other
\message{sectioning,}
% Define chapters, sections, etc.

\newcount \chapno
\newcount \secno        \secno=0
\newcount \subsecno     \subsecno=0
\newcount \subsubsecno  \subsubsecno=0

% This counter is funny since it counts through charcodes of letters A, B, ...
\newcount \appendixno  \appendixno = `\@
\def\appendixletter{\char\the\appendixno}

\newwrite \contentsfile
% This is called from \setfilename.
\def\opencontents{\openout \contentsfile = \jobname.toc}

% Each @chapter defines this as the name of the chapter.
% page headings and footings can use it.  @section does likewise

\def\thischapter{} \def\thissection{}
\def\seccheck#1{\if \pageno<0 %
\errmessage{@#1 not allowed after generating table of contents}\fi
%
}

\def\chapternofonts{%
\let\rawbackslash=\relax%
\let\frenchspacing=\relax%
\def\result{\realbackslash result}
\def\equiv{\realbackslash equiv}
\def\expansion{\realbackslash expansion}
\def\print{\realbackslash print}
\def\TeX{\realbackslash TeX}
\def\dots{\realbackslash dots}
\def\copyright{\realbackslash copyright}
\def\tt{\realbackslash tt}
\def\bf{\realbackslash bf }
\def\w{\realbackslash w}
\def\less{\realbackslash less}
\def\gtr{\realbackslash gtr}
\def\hat{\realbackslash hat}
\def\char{\realbackslash char}
\def\tclose##1{\realbackslash tclose {##1}}
\def\code##1{\realbackslash code {##1}}
\def\samp##1{\realbackslash samp {##1}}
\def\r##1{\realbackslash r {##1}}
\def\b##1{\realbackslash b {##1}}
\def\key##1{\realbackslash key {##1}}
\def\file##1{\realbackslash file {##1}}
\def\kbd##1{\realbackslash kbd {##1}}
% These are redefined because @smartitalic wouldn't work inside xdef.
\def\i##1{\realbackslash i {##1}}
\def\cite##1{\realbackslash cite {##1}}
\def\var##1{\realbackslash var {##1}}
\def\emph##1{\realbackslash emph {##1}}
\def\dfn##1{\realbackslash dfn {##1}}
}

\newcount\absseclevel % used to calculate proper heading level
\newcount\secbase\secbase=0 % @raise/lowersections modify this count

% @raisesections: treat @section as chapter, @subsection as section, etc.
\def\raisesections{\global\advance\secbase by -1}
\let\up=\raisesections % original BFox name

% @lowersections: treat @chapter as section, @section as subsection, etc.
\def\lowersections{\global\advance\secbase by 1}
\let\down=\lowersections % original BFox name

% Choose a numbered-heading macro
% #1 is heading level if unmodified by @raisesections or @lowersections
% #2 is text for heading
\def\numhead#1#2{\absseclevel=\secbase\advance\absseclevel by #1
\ifcase\absseclevel
  \chapterzzz{#2}
\or
  \seczzz{#2}
\or
  \numberedsubseczzz{#2}
\or
  \numberedsubsubseczzz{#2}
\else
  \ifnum \absseclevel<0
    \chapterzzz{#2}
  \else
    \numberedsubsubseczzz{#2}
  \fi
\fi
}

% like \numhead, but chooses appendix heading levels
\def\apphead#1#2{\absseclevel=\secbase\advance\absseclevel by #1
\ifcase\absseclevel
  \appendixzzz{#2}
\or
  \appendixsectionzzz{#2}
\or
  \appendixsubseczzz{#2}
\or
  \appendixsubsubseczzz{#2}
\else
  \ifnum \absseclevel<0
    \appendixzzz{#2}
  \else
    \appendixsubsubseczzz{#2}
  \fi
\fi
}

% like \numhead, but chooses numberless heading levels
\def\unnmhead#1#2{\absseclevel=\secbase\advance\absseclevel by #1
\ifcase\absseclevel
  \unnumberedzzz{#2}
\or
  \unnumberedseczzz{#2}
\or
  \unnumberedsubseczzz{#2}
\or
  \unnumberedsubsubseczzz{#2}
\else
  \ifnum \absseclevel<0
    \unnumberedzzz{#2}
  \else
    \unnumberedsubsubseczzz{#2}
  \fi
\fi
}


\def\thischaptername{No Chapter Title}
\outer\def\chapter{\parsearg\chapteryyy}
\def\chapteryyy #1{\numhead0{#1}} % normally numhead0 calls chapterzzz
\def\chapterzzz #1{\seccheck{chapter}%
\secno=0 \subsecno=0 \subsubsecno=0
\global\advance \chapno by 1 \message{Chapter \the\chapno}%
\chapmacro {#1}{\the\chapno}%
\gdef\thissection{#1}%
\gdef\thischaptername{#1}%
% We don't substitute the actual chapter name into \thischapter
% because we don't want its macros evaluated now.
\xdef\thischapter{\putwordChapter{} \the\chapno: \noexpand\thischaptername}%
{\chapternofonts%
\edef\temp{{\realbackslash chapentry {#1}{\the\chapno}{\noexpand\folio}}}%
\escapechar=`\\%
\write \contentsfile \temp  %
\donoderef %
\global\let\section = \numberedsec
\global\let\subsection = \numberedsubsec
\global\let\subsubsection = \numberedsubsubsec
}}

\outer\def\appendix{\parsearg\appendixyyy}
\def\appendixyyy #1{\apphead0{#1}} % normally apphead0 calls appendixzzz
\def\appendixzzz #1{\seccheck{appendix}%
\secno=0 \subsecno=0 \subsubsecno=0
\global\advance \appendixno by 1 \message{Appendix \appendixletter}%
\chapmacro {#1}{\putwordAppendix{} \appendixletter}%
\gdef\thissection{#1}%
\gdef\thischaptername{#1}%
\xdef\thischapter{\putwordAppendix{} \appendixletter: \noexpand\thischaptername}%
{\chapternofonts%
\edef\temp{{\realbackslash chapentry
  {#1}{\putwordAppendix{} \appendixletter}{\noexpand\folio}}}%
\escapechar=`\\%
\write \contentsfile \temp  %
\appendixnoderef %
\global\let\section = \appendixsec
\global\let\subsection = \appendixsubsec
\global\let\subsubsection = \appendixsubsubsec
}}

\outer\def\top{\parsearg\unnumberedyyy}
\outer\def\unnumbered{\parsearg\unnumberedyyy}
\def\unnumberedyyy #1{\unnmhead0{#1}} % normally unnmhead0 calls unnumberedzzz
\def\unnumberedzzz #1{\seccheck{unnumbered}%
\secno=0 \subsecno=0 \subsubsecno=0
%
% This used to be simply \message{#1}, but TeX fully expands the
% argument to \message.  Therefore, if #1 contained @-commands, TeX
% expanded them.  For example, in `@unnumbered The @cite{Book}', TeX
% expanded @cite (which turns out to cause errors because \cite is meant
% to be executed, not expanded).
%
% Anyway, we don't want the fully-expanded definition of @cite to appear
% as a result of the \message, we just want `@cite' itself.  We use
% \the<toks register> to achieve this: TeX expands \the<toks> only once,
% simply yielding the contents of the <toks register>.
\toks0 = {#1}\message{(\the\toks0)}%
%
\unnumbchapmacro {#1}%
\gdef\thischapter{#1}\gdef\thissection{#1}%
{\chapternofonts%
\edef\temp{{\realbackslash unnumbchapentry {#1}{\noexpand\folio}}}%
\escapechar=`\\%
\write \contentsfile \temp  %
\unnumbnoderef %
\global\let\section = \unnumberedsec
\global\let\subsection = \unnumberedsubsec
\global\let\subsubsection = \unnumberedsubsubsec
}}

\outer\def\numberedsec{\parsearg\secyyy}
\def\secyyy #1{\numhead1{#1}} % normally calls seczzz
\def\seczzz #1{\seccheck{section}%
\subsecno=0 \subsubsecno=0 \global\advance \secno by 1 %
\gdef\thissection{#1}\secheading {#1}{\the\chapno}{\the\secno}%
{\chapternofonts%
\edef\temp{{\realbackslash secentry %
{#1}{\the\chapno}{\the\secno}{\noexpand\folio}}}%
\escapechar=`\\%
\write \contentsfile \temp %
\donoderef %
\penalty 10000 %
}}

\outer\def\appenixsection{\parsearg\appendixsecyyy}
\outer\def\appendixsec{\parsearg\appendixsecyyy}
\def\appendixsecyyy #1{\apphead1{#1}} % normally calls appendixsectionzzz
\def\appendixsectionzzz #1{\seccheck{appendixsection}%
\subsecno=0 \subsubsecno=0 \global\advance \secno by 1 %
\gdef\thissection{#1}\secheading {#1}{\appendixletter}{\the\secno}%
{\chapternofonts%
\edef\temp{{\realbackslash secentry %
{#1}{\appendixletter}{\the\secno}{\noexpand\folio}}}%
\escapechar=`\\%
\write \contentsfile \temp %
\appendixnoderef %
\penalty 10000 %
}}

\outer\def\unnumberedsec{\parsearg\unnumberedsecyyy}
\def\unnumberedsecyyy #1{\unnmhead1{#1}} % normally calls unnumberedseczzz
\def\unnumberedseczzz #1{\seccheck{unnumberedsec}%
\plainsecheading {#1}\gdef\thissection{#1}%
{\chapternofonts%
\edef\temp{{\realbackslash unnumbsecentry{#1}{\noexpand\folio}}}%
\escapechar=`\\%
\write \contentsfile \temp %
\unnumbnoderef %
\penalty 10000 %
}}

\outer\def\numberedsubsec{\parsearg\numberedsubsecyyy}
\def\numberedsubsecyyy #1{\numhead2{#1}} % normally calls numberedsubseczzz
\def\numberedsubseczzz #1{\seccheck{subsection}%
\gdef\thissection{#1}\subsubsecno=0 \global\advance \subsecno by 1 %
\subsecheading {#1}{\the\chapno}{\the\secno}{\the\subsecno}%
{\chapternofonts%
\edef\temp{{\realbackslash subsecentry %
{#1}{\the\chapno}{\the\secno}{\the\subsecno}{\noexpand\folio}}}%
\escapechar=`\\%
\write \contentsfile \temp %
\donoderef %
\penalty 10000 %
}}

\outer\def\appendixsubsec{\parsearg\appendixsubsecyyy}
\def\appendixsubsecyyy #1{\apphead2{#1}} % normally calls appendixsubseczzz
\def\appendixsubseczzz #1{\seccheck{appendixsubsec}%
\gdef\thissection{#1}\subsubsecno=0 \global\advance \subsecno by 1 %
\subsecheading {#1}{\appendixletter}{\the\secno}{\the\subsecno}%
{\chapternofonts%
\edef\temp{{\realbackslash subsecentry %
{#1}{\appendixletter}{\the\secno}{\the\subsecno}{\noexpand\folio}}}%
\escapechar=`\\%
\write \contentsfile \temp %
\appendixnoderef %
\penalty 10000 %
}}

\outer\def\unnumberedsubsec{\parsearg\unnumberedsubsecyyy}
\def\unnumberedsubsecyyy #1{\unnmhead2{#1}} %normally calls unnumberedsubseczzz
\def\unnumberedsubseczzz #1{\seccheck{unnumberedsubsec}%
\plainsecheading {#1}\gdef\thissection{#1}%
{\chapternofonts%
\edef\temp{{\realbackslash unnumbsubsecentry{#1}{\noexpand\folio}}}%
\escapechar=`\\%
\write \contentsfile \temp %
\unnumbnoderef %
\penalty 10000 %
}}

\outer\def\numberedsubsubsec{\parsearg\numberedsubsubsecyyy}
\def\numberedsubsubsecyyy #1{\numhead3{#1}} % normally numberedsubsubseczzz
\def\numberedsubsubseczzz #1{\seccheck{subsubsection}%
\gdef\thissection{#1}\global\advance \subsubsecno by 1 %
\subsubsecheading {#1}
  {\the\chapno}{\the\secno}{\the\subsecno}{\the\subsubsecno}%
{\chapternofonts%
\edef\temp{{\realbackslash subsubsecentry %
  {#1}
  {\the\chapno}{\the\secno}{\the\subsecno}{\the\subsubsecno}
  {\noexpand\folio}}}%
\escapechar=`\\%
\write \contentsfile \temp %
\donoderef %
\penalty 10000 %
}}

\outer\def\appendixsubsubsec{\parsearg\appendixsubsubsecyyy}
\def\appendixsubsubsecyyy #1{\apphead3{#1}} % normally appendixsubsubseczzz
\def\appendixsubsubseczzz #1{\seccheck{appendixsubsubsec}%
\gdef\thissection{#1}\global\advance \subsubsecno by 1 %
\subsubsecheading {#1}
  {\appendixletter}{\the\secno}{\the\subsecno}{\the\subsubsecno}%
{\chapternofonts%
\edef\temp{{\realbackslash subsubsecentry{#1}%
  {\appendixletter}
  {\the\secno}{\the\subsecno}{\the\subsubsecno}{\noexpand\folio}}}%
\escapechar=`\\%
\write \contentsfile \temp %
\appendixnoderef %
\penalty 10000 %
}}

\outer\def\unnumberedsubsubsec{\parsearg\unnumberedsubsubsecyyy}
\def\unnumberedsubsubsecyyy #1{\unnmhead3{#1}} %normally unnumberedsubsubseczzz
\def\unnumberedsubsubseczzz #1{\seccheck{unnumberedsubsubsec}%
\plainsecheading {#1}\gdef\thissection{#1}%
{\chapternofonts%
\edef\temp{{\realbackslash unnumbsubsubsecentry{#1}{\noexpand\folio}}}%
\escapechar=`\\%
\write \contentsfile \temp %
\unnumbnoderef %
\penalty 10000 %
}}

% These are variants which are not "outer", so they can appear in @ifinfo.
% Actually, they should now be obsolete; ordinary section commands should work.
\def\infotop{\parsearg\unnumberedzzz}
\def\infounnumbered{\parsearg\unnumberedzzz}
\def\infounnumberedsec{\parsearg\unnumberedseczzz}
\def\infounnumberedsubsec{\parsearg\unnumberedsubseczzz}
\def\infounnumberedsubsubsec{\parsearg\unnumberedsubsubseczzz}

\def\infoappendix{\parsearg\appendixzzz}
\def\infoappendixsec{\parsearg\appendixseczzz}
\def\infoappendixsubsec{\parsearg\appendixsubseczzz}
\def\infoappendixsubsubsec{\parsearg\appendixsubsubseczzz}

\def\infochapter{\parsearg\chapterzzz}
\def\infosection{\parsearg\sectionzzz}
\def\infosubsection{\parsearg\subsectionzzz}
\def\infosubsubsection{\parsearg\subsubsectionzzz}

% These macros control what the section commands do, according
% to what kind of chapter we are in (ordinary, appendix, or unnumbered).
% Define them by default for a numbered chapter.
\global\let\section = \numberedsec
\global\let\subsection = \numberedsubsec
\global\let\subsubsection = \numberedsubsubsec

% Define @majorheading, @heading and @subheading

% NOTE on use of \vbox for chapter headings, section headings, and
% such:
%       1) We use \vbox rather than the earlier \line to permit
%          overlong headings to fold.
%       2) \hyphenpenalty is set to 10000 because hyphenation in a
%          heading is obnoxious; this forbids it.
%       3) Likewise, headings look best if no \parindent is used, and
%          if justification is not attempted.  Hence \raggedright.


\def\majorheading{\parsearg\majorheadingzzz}
\def\majorheadingzzz #1{%
{\advance\chapheadingskip by 10pt \chapbreak }%
{\chapfonts \vbox{\hyphenpenalty=10000\tolerance=5000
                  \parindent=0pt\raggedright
                  \rm #1\hfill}}\bigskip \par\penalty 200}

\def\chapheading{\parsearg\chapheadingzzz}
\def\chapheadingzzz #1{\chapbreak %
{\chapfonts \vbox{\hyphenpenalty=10000\tolerance=5000
                  \parindent=0pt\raggedright
                  \rm #1\hfill}}\bigskip \par\penalty 200}

\def\heading{\parsearg\secheadingi}

\def\subheading{\parsearg\subsecheadingi}

\def\subsubheading{\parsearg\subsubsecheadingi}

% These macros generate a chapter, section, etc. heading only
% (including whitespace, linebreaking, etc. around it),
% given all the information in convenient, parsed form.

%%% Args are the skip and penalty (usually negative)
\def\dobreak#1#2{\par\ifdim\lastskip<#1\removelastskip\penalty#2\vskip#1\fi}

\def\setchapterstyle #1 {\csname CHAPF#1\endcsname}

%%% Define plain chapter starts, and page on/off switching for it
% Parameter controlling skip before chapter headings (if needed)

\newskip \chapheadingskip \chapheadingskip = 30pt plus 8pt minus 4pt

\def\chapbreak{\dobreak \chapheadingskip {-4000}}
\def\chappager{\par\vfill\supereject}
\def\chapoddpage{\chappager \ifodd\pageno \else \hbox to 0pt{} \chappager\fi}

\def\setchapternewpage #1 {\csname CHAPPAG#1\endcsname}

\def\CHAPPAGoff{
\global\let\pchapsepmacro=\chapbreak
\global\let\pagealignmacro=\chappager}

\def\CHAPPAGon{
\global\let\pchapsepmacro=\chappager
\global\let\pagealignmacro=\chappager
\global\def\HEADINGSon{\HEADINGSsingle}}

\def\CHAPPAGodd{
\global\let\pchapsepmacro=\chapoddpage
\global\let\pagealignmacro=\chapoddpage
\global\def\HEADINGSon{\HEADINGSdouble}}

\CHAPPAGon

\def\CHAPFplain{
\global\let\chapmacro=\chfplain
\global\let\unnumbchapmacro=\unnchfplain}

\def\chfplain #1#2{%
  \pchapsepmacro
  {%
    \chapfonts \vbox{\hyphenpenalty=10000\tolerance=5000
                     \parindent=0pt\raggedright
                     \rm #2\enspace #1}%
  }%
  \bigskip
  \penalty5000
}

\def\unnchfplain #1{%
\pchapsepmacro %
{\chapfonts \vbox{\hyphenpenalty=10000\tolerance=5000
                  \parindent=0pt\raggedright
                  \rm #1\hfill}}\bigskip \par\penalty 10000 %
}
\CHAPFplain % The default

\def\unnchfopen #1{%
\chapoddpage {\chapfonts \vbox{\hyphenpenalty=10000\tolerance=5000
                       \parindent=0pt\raggedright
                       \rm #1\hfill}}\bigskip \par\penalty 10000 %
}

\def\chfopen #1#2{\chapoddpage {\chapfonts
\vbox to 3in{\vfil \hbox to\hsize{\hfil #2} \hbox to\hsize{\hfil #1} \vfil}}%
\par\penalty 5000 %
}

\def\CHAPFopen{
\global\let\chapmacro=\chfopen
\global\let\unnumbchapmacro=\unnchfopen}

% Parameter controlling skip before section headings.

\newskip \subsecheadingskip  \subsecheadingskip = 17pt plus 8pt minus 4pt
\def\subsecheadingbreak{\dobreak \subsecheadingskip {-500}}

\newskip \secheadingskip  \secheadingskip = 21pt plus 8pt minus 4pt
\def\secheadingbreak{\dobreak \secheadingskip {-1000}}

% @paragraphindent  is defined for the Info formatting commands only.
\let\paragraphindent=\comment

% Section fonts are the base font at magstep2, which produces
% a size a bit more than 14 points in the default situation.

\def\secheading #1#2#3{\secheadingi {#2.#3\enspace #1}}
\def\plainsecheading #1{\secheadingi {#1}}
\def\secheadingi #1{{\advance \secheadingskip by \parskip %
\secheadingbreak}%
{\secfonts \vbox{\hyphenpenalty=10000\tolerance=5000
                 \parindent=0pt\raggedright
                 \rm #1\hfill}}%
\ifdim \parskip<10pt \kern 10pt\kern -\parskip\fi \penalty 10000 }


% Subsection fonts are the base font at magstep1,
% which produces a size of 12 points.

\def\subsecheading #1#2#3#4{\subsecheadingi {#2.#3.#4\enspace #1}}
\def\subsecheadingi #1{{\advance \subsecheadingskip by \parskip %
\subsecheadingbreak}%
{\subsecfonts \vbox{\hyphenpenalty=10000\tolerance=5000
                     \parindent=0pt\raggedright
                     \rm #1\hfill}}%
\ifdim \parskip<10pt \kern 10pt\kern -\parskip\fi \penalty 10000 }

\def\subsubsecfonts{\subsecfonts} % Maybe this should change:
                                  % Perhaps make sssec fonts scaled
                                  % magstep half
\def\subsubsecheading #1#2#3#4#5{\subsubsecheadingi {#2.#3.#4.#5\enspace #1}}
\def\subsubsecheadingi #1{{\advance \subsecheadingskip by \parskip %
\subsecheadingbreak}%
{\subsubsecfonts \vbox{\hyphenpenalty=10000\tolerance=5000
                       \parindent=0pt\raggedright
                       \rm #1\hfill}}%
\ifdim \parskip<10pt \kern 10pt\kern -\parskip\fi \penalty 10000}


\message{toc printing,}

% Finish up the main text and prepare to read what we've written
% to \contentsfile.

\newskip\contentsrightmargin \contentsrightmargin=1in
\def\startcontents#1{%
   \pagealignmacro
   \immediate\closeout \contentsfile
   \ifnum \pageno>0
      \pageno = -1              % Request roman numbered pages.
   \fi
   % Don't need to put `Contents' or `Short Contents' in the headline.
   % It is abundantly clear what they are.
   \unnumbchapmacro{#1}\def\thischapter{}%
   \begingroup                  % Set up to handle contents files properly.
      \catcode`\\=0  \catcode`\{=1  \catcode`\}=2  \catcode`\@=11
      \raggedbottom             % Worry more about breakpoints than the bottom.
      \advance\hsize by -\contentsrightmargin % Don't use the full line length.
}


% Normal (long) toc.
\outer\def\contents{%
   \startcontents{\putwordTableofContents}%
      \input \jobname.toc
   \endgroup
   \vfill \eject
}

% And just the chapters.
\outer\def\summarycontents{%
   \startcontents{\putwordShortContents}%
      %
      \let\chapentry = \shortchapentry
      \let\unnumbchapentry = \shortunnumberedentry
      % We want a true roman here for the page numbers.
      \secfonts
      \let\rm=\shortcontrm \let\bf=\shortcontbf \let\sl=\shortcontsl
      \rm
      \advance\baselineskip by 1pt % Open it up a little.
      \def\secentry ##1##2##3##4{}
      \def\unnumbsecentry ##1##2{}
      \def\subsecentry ##1##2##3##4##5{}
      \def\unnumbsubsecentry ##1##2{}
      \def\subsubsecentry ##1##2##3##4##5##6{}
      \def\unnumbsubsubsecentry ##1##2{}
      \input \jobname.toc
   \endgroup
   \vfill \eject
}
\let\shortcontents = \summarycontents

% These macros generate individual entries in the table of contents.
% The first argument is the chapter or section name.
% The last argument is the page number.
% The arguments in between are the chapter number, section number, ...

% Chapter-level things, for both the long and short contents.
\def\chapentry#1#2#3{\dochapentry{#2\labelspace#1}{#3}}

% See comments in \dochapentry re vbox and related settings
\def\shortchapentry#1#2#3{%
  \tocentry{\shortchaplabel{#2}\labelspace #1}{\doshortpageno{#3}}%
}

% Typeset the label for a chapter or appendix for the short contents.
% The arg is, e.g. `Appendix A' for an appendix, or `3' for a chapter.
% We could simplify the code here by writing out an \appendixentry
% command in the toc file for appendices, instead of using \chapentry
% for both, but it doesn't seem worth it.
\setbox0 = \hbox{\shortcontrm \putwordAppendix }
\newdimen\shortappendixwidth \shortappendixwidth = \wd0

\def\shortchaplabel#1{%
  % We typeset #1 in a box of constant width, regardless of the text of
  % #1, so the chapter titles will come out aligned.
  \setbox0 = \hbox{#1}%
  \dimen0 = \ifdim\wd0 > \shortappendixwidth \shortappendixwidth \else 0pt \fi
  %
  % This space should be plenty, since a single number is .5em, and the
  % widest letter (M) is 1em, at least in the Computer Modern fonts.
  % (This space doesn't include the extra space that gets added after
  % the label; that gets put in in \shortchapentry above.)
  \advance\dimen0 by 1.1em
  \hbox to \dimen0{#1\hfil}%
}

\def\unnumbchapentry#1#2{\dochapentry{#1}{#2}}
\def\shortunnumberedentry#1#2{\tocentry{#1}{\doshortpageno{#2}}}

% Sections.
\def\secentry#1#2#3#4{\dosecentry{#2.#3\labelspace#1}{#4}}
\def\unnumbsecentry#1#2{\dosecentry{#1}{#2}}

% Subsections.
\def\subsecentry#1#2#3#4#5{\dosubsecentry{#2.#3.#4\labelspace#1}{#5}}
\def\unnumbsubsecentry#1#2{\dosubsecentry{#1}{#2}}

% And subsubsections.
\def\subsubsecentry#1#2#3#4#5#6{%
  \dosubsubsecentry{#2.#3.#4.#5\labelspace#1}{#6}}
\def\unnumbsubsubsecentry#1#2{\dosubsubsecentry{#1}{#2}}


% This parameter controls the indentation of the various levels.
\newdimen\tocindent \tocindent = 3pc

% Now for the actual typesetting. In all these, #1 is the text and #2 is the
% page number.
%
% If the toc has to be broken over pages, we would want to be at chapters
% if at all possible; hence the \penalty.
\def\dochapentry#1#2{%
   \penalty-300 \vskip\baselineskip
   \begingroup
     \chapentryfonts
     \tocentry{#1}{\dopageno{#2}}%
   \endgroup
   \nobreak\vskip .25\baselineskip
}

\def\dosecentry#1#2{\begingroup
  \secentryfonts \leftskip=\tocindent
  \tocentry{#1}{\dopageno{#2}}%
\endgroup}

\def\dosubsecentry#1#2{\begingroup
  \subsecentryfonts \leftskip=2\tocindent
  \tocentry{#1}{\dopageno{#2}}%
\endgroup}

\def\dosubsubsecentry#1#2{\begingroup
  \subsubsecentryfonts \leftskip=3\tocindent
  \tocentry{#1}{\dopageno{#2}}%
\endgroup}

% Final typesetting of a toc entry; we use the same \entry macro as for
% the index entries, but we want to suppress hyphenation here.  (We
% can't do that in the \entry macro, since index entries might consist
% of hyphenated-identifiers-that-do-not-fit-on-a-line-and-nothing-else.)
%
\def\tocentry#1#2{\begingroup
  \hyphenpenalty = 10000
  \entry{#1}{#2}%
\endgroup}

% Space between chapter (or whatever) number and the title.
\def\labelspace{\hskip1em \relax}

\def\dopageno#1{{\rm #1}}
\def\doshortpageno#1{{\rm #1}}

\def\chapentryfonts{\secfonts \rm}
\def\secentryfonts{\textfonts}
\let\subsecentryfonts = \textfonts
\let\subsubsecentryfonts = \textfonts


\message{environments,}

% Since these characters are used in examples, it should be an even number of
% \tt widths. Each \tt character is 1en, so two makes it 1em.
% Furthermore, these definitions must come after we define our fonts.
\newbox\dblarrowbox    \newbox\longdblarrowbox
\newbox\pushcharbox    \newbox\bullbox
\newbox\equivbox       \newbox\errorbox

\let\ptexequiv = \equiv

%{\tentt
%\global\setbox\dblarrowbox = \hbox to 1em{\hfil$\Rightarrow$\hfil}
%\global\setbox\longdblarrowbox = \hbox to 1em{\hfil$\mapsto$\hfil}
%\global\setbox\pushcharbox = \hbox to 1em{\hfil$\dashv$\hfil}
%\global\setbox\equivbox = \hbox to 1em{\hfil$\ptexequiv$\hfil}
% Adapted from the manmac format (p.420 of TeXbook)
%\global\setbox\bullbox = \hbox to 1em{\kern.15em\vrule height .75ex width .85ex
%                                      depth .1ex\hfil}
%}

\def\point{$\star$}

\def\result{\leavevmode\raise.15ex\hbox to 1em{\hfil$\Rightarrow$\hfil}}
\def\expansion{\leavevmode\raise.1ex\hbox to 1em{\hfil$\mapsto$\hfil}}
\def\print{\leavevmode\lower.1ex\hbox to 1em{\hfil$\dashv$\hfil}}

\def\equiv{\leavevmode\lower.1ex\hbox to 1em{\hfil$\ptexequiv$\hfil}}

% Adapted from the TeXbook's \boxit.
{\tentt \global\dimen0 = 3em}% Width of the box.
\dimen2 = .55pt % Thickness of rules
% The text. (`r' is open on the right, `e' somewhat less so on the left.)
\setbox0 = \hbox{\kern-.75pt \tensf error\kern-1.5pt}

\global\setbox\errorbox=\hbox to \dimen0{\hfil
   \hsize = \dimen0 \advance\hsize by -5.8pt % Space to left+right.
   \advance\hsize by -2\dimen2 % Rules.
   \vbox{
      \hrule height\dimen2
      \hbox{\vrule width\dimen2 \kern3pt          % Space to left of text.
         \vtop{\kern2.4pt \box0 \kern2.4pt}% Space above/below.
         \kern3pt\vrule width\dimen2}% Space to right.
      \hrule height\dimen2}
    \hfil}

% The @error{} command.
\def\error{\leavevmode\lower.7ex\copy\errorbox}

% @tex ... @end tex    escapes into raw Tex temporarily.
% One exception: @ is still an escape character, so that @end tex works.
% But \@ or @@ will get a plain tex @ character.

\def\tex{\begingroup
\catcode `\\=0 \catcode `\{=1 \catcode `\}=2
\catcode `\$=3 \catcode `\&=4 \catcode `\#=6
\catcode `\^=7 \catcode `\_=8 \catcode `\~=13 \let~=\tie
\catcode `\%=14
\catcode 43=12
\catcode`\"=12
\catcode`\==12
\catcode`\|=12
\catcode`\<=12
\catcode`\>=12
\escapechar=`\\
%
\let\~=\ptextilde
\let\{=\ptexlbrace
\let\}=\ptexrbrace
\let\.=\ptexdot
\let\*=\ptexstar
\let\dots=\ptexdots
\def\@{@}%
\let\bullet=\ptexbullet
\let\b=\ptexb \let\c=\ptexc \let\i=\ptexi \let\t=\ptext \let\l=\ptexl
\let\L=\ptexL
%
\let\Etex=\endgroup}

% Define @lisp ... @endlisp.
% @lisp does a \begingroup so it can rebind things,
% including the definition of @endlisp (which normally is erroneous).

% Amount to narrow the margins by for @lisp.
\newskip\lispnarrowing \lispnarrowing=0.4in

% This is the definition that ^^M gets inside @lisp, @example, and other
% such environments.  \null is better than a space, since it doesn't
% have any width.
\def\lisppar{\null\endgraf}

% Make each space character in the input produce a normal interword
% space in the output.  Don't allow a line break at this space, as this
% is used only in environments like @example, where each line of input
% should produce a line of output anyway.
%
{\obeyspaces %
\gdef\sepspaces{\obeyspaces\let =\tie}}

% Define \obeyedspace to be our active space, whatever it is.  This is
% for use in \parsearg.
{\sepspaces%
\global\let\obeyedspace= }

% This space is always present above and below environments.
\newskip\envskipamount \envskipamount = 0pt

% Make spacing and below environment symmetrical.  We use \parskip here
% to help in doing that, since in @example-like environments \parskip
% is reset to zero; thus the \afterenvbreak inserts no space -- but the
% start of the next paragraph will insert \parskip
%
\def\aboveenvbreak{{\advance\envskipamount by \parskip
\endgraf \ifdim\lastskip<\envskipamount
\removelastskip \penalty-50 \vskip\envskipamount \fi}}

\let\afterenvbreak = \aboveenvbreak

% \nonarrowing is a flag.  If "set", @lisp etc don't narrow margins.
\let\nonarrowing=\relax

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% \cartouche: draw rectangle w/rounded corners around argument
\font\circle=lcircle10
\newdimen\circthick
\newdimen\cartouter\newdimen\cartinner
\newskip\normbskip\newskip\normpskip\newskip\normlskip
\circthick=\fontdimen8\circle
%
\def\ctl{{\circle\char'013\hskip -6pt}}% 6pt from pl file: 1/2charwidth
\def\ctr{{\hskip 6pt\circle\char'010}}
\def\cbl{{\circle\char'012\hskip -6pt}}
\def\cbr{{\hskip 6pt\circle\char'011}}
\def\carttop{\hbox to \cartouter{\hskip\lskip
        \ctl\leaders\hrule height\circthick\hfil\ctr
        \hskip\rskip}}
\def\cartbot{\hbox to \cartouter{\hskip\lskip
        \cbl\leaders\hrule height\circthick\hfil\cbr
        \hskip\rskip}}
%
\newskip\lskip\newskip\rskip

\long\def\cartouche{%
\begingroup
        \lskip=\leftskip \rskip=\rightskip
        \leftskip=0pt\rightskip=0pt %we want these *outside*.
        \cartinner=\hsize \advance\cartinner by-\lskip
                          \advance\cartinner by-\rskip
        \cartouter=\hsize
        \advance\cartouter by 18pt % allow for 3pt kerns on either
%                                    side, and for 6pt waste from
%                                    each corner char
        \normbskip=\baselineskip \normpskip=\parskip \normlskip=\lineskip
        % Flag to tell @lisp, etc., not to narrow margin.
        \let\nonarrowing=\comment
        \vbox\bgroup
                \baselineskip=0pt\parskip=0pt\lineskip=0pt
                \carttop
                \hbox\bgroup
                        \hskip\lskip
                        \vrule\kern3pt
                        \vbox\bgroup
                                \hsize=\cartinner
                                \kern3pt
                                \begingroup
                                        \baselineskip=\normbskip
                                        \lineskip=\normlskip
                                        \parskip=\normpskip
                                        \vskip -\parskip
\def\Ecartouche{%
                                \endgroup
                                \kern3pt
                        \egroup
                        \kern3pt\vrule
                        \hskip\rskip
                \egroup
                \cartbot
        \egroup
\endgroup
}}


% This macro is called at the beginning of all the @example variants,
% inside a group.
\def\nonfillstart{%
  \aboveenvbreak
  \inENV % This group ends at the end of the body
  \hfuzz = 12pt % Don't be fussy
  \sepspaces % Make spaces be word-separators rather than space tokens.
  \singlespace
  \let\par = \lisppar % don't ignore blank lines
  \obeylines % each line of input is a line of output
  \parskip = 0pt
  \parindent = 0pt
  \emergencystretch = 0pt % don't try to avoid overfull boxes
  % @cartouche defines \nonarrowing to inhibit narrowing
  % at next level down.
  \ifx\nonarrowing\relax
    \advance \leftskip by \lispnarrowing
    \exdentamount=\lispnarrowing
    \let\exdent=\nofillexdent
    \let\nonarrowing=\relax
  \fi
}

% To ending an @example-like environment, we first end the paragraph
% (via \afterenvbreak's vertical glue), and then the group.  That way we
% keep the zero \parskip that the environments set -- \parskip glue
% will be inserted at the beginning of the next paragraph in the
% document, after the environment.
%
\def\nonfillfinish{\afterenvbreak\endgroup}%

% This macro is
\def\lisp{\begingroup
  \nonfillstart
  \let\Elisp = \nonfillfinish
  \tt
  \rawbackslash % have \ input char produce \ char from current font
  \gobble
}

% Define the \E... control sequence only if we are inside the
% environment, so the error checking in \end will work.
%
% We must call \lisp last in the definition, since it reads the
% return following the @example (or whatever) command.
%
\def\example{\begingroup \def\Eexample{\nonfillfinish\endgroup}\lisp}
\def\smallexample{\begingroup \def\Esmallexample{\nonfillfinish\endgroup}\lisp}
\def\smalllisp{\begingroup \def\Esmalllisp{\nonfillfinish\endgroup}\lisp}

% @smallexample and @smalllisp.  This is not used unless the @smallbook
% command is given.  Originally contributed by Pavel@xerox.
%
\def\smalllispx{\begingroup
  \nonfillstart
  \let\Esmalllisp = \nonfillfinish
  \let\Esmallexample = \nonfillfinish
  %
  % Smaller interline space and fonts for small examples.
  \setleading{10pt}%
  \indexfonts \tt
  \rawbackslash % make \ output the \ character from the current font (tt)
  \gobble
}

% This is @display; same as @lisp except use roman font.
%
\def\display{\begingroup
  \nonfillstart
  \let\Edisplay = \nonfillfinish
  \gobble
}

% This is @format; same as @display except don't narrow margins.
%
\def\format{\begingroup
  \let\nonarrowing = t
  \nonfillstart
  \let\Eformat = \nonfillfinish
  \gobble
}

% @flushleft (same as @format) and @flushright.
%
\def\flushleft{\begingroup
  \let\nonarrowing = t
  \nonfillstart
  \let\Eflushleft = \nonfillfinish
  \gobble
}
\def\flushright{\begingroup
  \let\nonarrowing = t
  \nonfillstart
  \let\Eflushright = \nonfillfinish
  \advance\leftskip by 0pt plus 1fill
  \gobble}

% @quotation does normal linebreaking and narrows the margins.
%
\def\quotation{%
\begingroup\inENV %This group ends at the end of the @quotation body
{\parskip=0pt  % because we will skip by \parskip too, later
\aboveenvbreak}%
\singlespace
\parindent=0pt
\let\Equotation = \nonfillfinish
% @cartouche defines \nonarrowing to inhibit narrowing
% at next level down.
\ifx\nonarrowing\relax
\advance \leftskip by \lispnarrowing
\advance \rightskip by \lispnarrowing
\exdentamount=\lispnarrowing
\let\nonarrowing=\relax
\fi}

\message{defuns,}
% Define formatter for defuns
% First, allow user to change definition object font (\df) internally
\def\setdeffont #1 {\csname DEF#1\endcsname}

\newskip\defbodyindent \defbodyindent=.4in
\newskip\defargsindent \defargsindent=50pt
\newskip\deftypemargin \deftypemargin=12pt
\newskip\deflastargmargin \deflastargmargin=18pt

\newcount\parencount
% define \functionparens, which makes ( and ) and & do special things.
% \functionparens affects the group it is contained in.
\def\activeparens{%
\catcode`\(=\active \catcode`\)=\active \catcode`\&=\active
\catcode`\[=\active \catcode`\]=\active}

% Make control sequences which act like normal parenthesis chars.
\let\lparen = ( \let\rparen = )

{\activeparens % Now, smart parens don't turn on until &foo (see \amprm)

% Be sure that we always have a definition for `(', etc.  For example,
% if the fn name has parens in it, \boldbrax will not be in effect yet,
% so TeX would otherwise complain about undefined control sequence.
\global\let(=\lparen \global\let)=\rparen
\global\let[=\lbrack \global\let]=\rbrack

\gdef\functionparens{\boldbrax\let&=\amprm\parencount=0 }
\gdef\boldbrax{\let(=\opnr\let)=\clnr\let[=\lbrb\let]=\rbrb}

% Definitions of (, ) and & used in args for functions.
% This is the definition of ( outside of all parentheses.
\gdef\oprm#1 {{\rm\char`\(}#1 \bf \let(=\opnested %
\global\advance\parencount by 1 }
%
% This is the definition of ( when already inside a level of parens.
\gdef\opnested{\char`\(\global\advance\parencount by 1 }
%
\gdef\clrm{% Print a paren in roman if it is taking us back to depth of 0.
% also in that case restore the outer-level definition of (.
\ifnum \parencount=1 {\rm \char `\)}\sl \let(=\oprm \else \char `\) \fi
\global\advance \parencount by -1 }
% If we encounter &foo, then turn on ()-hacking afterwards
\gdef\amprm#1 {{\rm\&#1}\let(=\oprm \let)=\clrm\ }
%
\gdef\normalparens{\boldbrax\let&=\ampnr}
} % End of definition inside \activeparens
%% These parens (in \boldbrax) actually are a little bolder than the
%% contained text.  This is especially needed for [ and ]
\def\opnr{{\sf\char`\(}} \def\clnr{{\sf\char`\)}} \def\ampnr{\&}
\def\lbrb{{\bf\char`\[}} \def\rbrb{{\bf\char`\]}}

% First, defname, which formats the header line itself.
% #1 should be the function name.
% #2 should be the type of definition, such as "Function".

\def\defname #1#2{%
% Get the values of \leftskip and \rightskip as they were
% outside the @def...
\dimen2=\leftskip
\advance\dimen2 by -\defbodyindent
\dimen3=\rightskip
\advance\dimen3 by -\defbodyindent
\noindent        %
\setbox0=\hbox{\hskip \deflastargmargin{\rm #2}\hskip \deftypemargin}%
\dimen0=\hsize \advance \dimen0 by -\wd0 % compute size for first line
\dimen1=\hsize \advance \dimen1 by -\defargsindent %size for continuations
\parshape 2 0in \dimen0 \defargsindent \dimen1     %
% Now output arg 2 ("Function" or some such)
% ending at \deftypemargin from the right margin,
% but stuck inside a box of width 0 so it does not interfere with linebreaking
{% Adjust \hsize to exclude the ambient margins,
% so that \rightline will obey them.
\advance \hsize by -\dimen2 \advance \hsize by -\dimen3
\rlap{\rightline{{\rm #2}\hskip \deftypemargin}}}%
% Make all lines underfull and no complaints:
\tolerance=10000 \hbadness=10000
\advance\leftskip by -\defbodyindent
\exdentamount=\defbodyindent
{\df #1}\enskip        % Generate function name
}

% Actually process the body of a definition
% #1 should be the terminating control sequence, such as \Edefun.
% #2 should be the "another name" control sequence, such as \defunx.
% #3 should be the control sequence that actually processes the header,
%    such as \defunheader.

\def\defparsebody #1#2#3{\begingroup\inENV% Environment for definitionbody
\medbreak %
% Define the end token that this defining construct specifies
% so that it will exit this group.
\def#1{\endgraf\endgroup\medbreak}%
\def#2{\begingroup\obeylines\activeparens\spacesplit#3}%
\parindent=0in
\advance\leftskip by \defbodyindent \advance \rightskip by \defbodyindent
\exdentamount=\defbodyindent
\begingroup %
\catcode 61=\active % 61 is `='
\obeylines\activeparens\spacesplit#3}

\def\defmethparsebody #1#2#3#4 {\begingroup\inENV %
\medbreak %
% Define the end token that this defining construct specifies
% so that it will exit this group.
\def#1{\endgraf\endgroup\medbreak}%
\def#2##1 {\begingroup\obeylines\activeparens\spacesplit{#3{##1}}}%
\parindent=0in
\advance\leftskip by \defbodyindent \advance \rightskip by \defbodyindent
\exdentamount=\defbodyindent
\begingroup\obeylines\activeparens\spacesplit{#3{#4}}}

\def\defopparsebody #1#2#3#4#5 {\begingroup\inENV %
\medbreak %
% Define the end token that this defining construct specifies
% so that it will exit this group.
\def#1{\endgraf\endgroup\medbreak}%
\def#2##1 ##2 {\def#4{##1}%
\begingroup\obeylines\activeparens\spacesplit{#3{##2}}}%
\parindent=0in
\advance\leftskip by \defbodyindent \advance \rightskip by \defbodyindent
\exdentamount=\defbodyindent
\begingroup\obeylines\activeparens\spacesplit{#3{#5}}}

% These parsing functions are similar to the preceding ones
% except that they do not make parens into active characters.
% These are used for "variables" since they have no arguments.

\def\defvarparsebody #1#2#3{\begingroup\inENV% Environment for definitionbody
\medbreak %
% Define the end token that this defining construct specifies
% so that it will exit this group.
\def#1{\endgraf\endgroup\medbreak}%
\def#2{\begingroup\obeylines\spacesplit#3}%
\parindent=0in
\advance\leftskip by \defbodyindent \advance \rightskip by \defbodyindent
\exdentamount=\defbodyindent
\begingroup %
\catcode 61=\active %
\obeylines\spacesplit#3}

% This is used for \def{tp,vr}parsebody.  It could probably be used for
% some of the others, too, with some judicious conditionals.
%
\def\parsebodycommon#1#2#3{%
  \begingroup\inENV %
  \medbreak %
  % Define the end token that this defining construct specifies
  % so that it will exit this group.
  \def#1{\endgraf\endgroup\medbreak}%
  \def#2##1 {\begingroup\obeylines\spacesplit{#3{##1}}}%
  \parindent=0in
  \advance\leftskip by \defbodyindent \advance \rightskip by \defbodyindent
  \exdentamount=\defbodyindent
  \begingroup\obeylines
}

\def\defvrparsebody#1#2#3#4 {%
  \parsebodycommon{#1}{#2}{#3}%
  \spacesplit{#3{#4}}%
}

% This loses on `@deftp {Data Type} {struct termios}' -- it thinks the
% type is just `struct', because we lose the braces in `{struct
% termios}' when \spacesplit reads its undelimited argument.  Sigh.
% \let\deftpparsebody=\defvrparsebody
%
% So, to get around this, we put \empty in with the type name.  That
% way, TeX won't find exactly `{...}' as an undelimited argument, and
% won't strip off the braces.
%
\def\deftpparsebody #1#2#3#4 {%
  \parsebodycommon{#1}{#2}{#3}%
  \spacesplit{\parsetpheaderline{#3{#4}}}\empty
}

% Fine, but then we have to eventually remove the \empty *and* the
% braces (if any).  That's what this does, putting the result in \tptemp.
%
\def\removeemptybraces\empty#1\relax{\def\tptemp{#1}}%

% After \spacesplit has done its work, this is called -- #1 is the final
% thing to call, #2 the type name (which starts with \empty), and #3
% (which might be empty) the arguments.
%
\def\parsetpheaderline#1#2#3{%
  \removeemptybraces#2\relax
  #1{\tptemp}{#3}%
}%

\def\defopvarparsebody #1#2#3#4#5 {\begingroup\inENV %
\medbreak %
% Define the end token that this defining construct specifies
% so that it will exit this group.
\def#1{\endgraf\endgroup\medbreak}%
\def#2##1 ##2 {\def#4{##1}%
\begingroup\obeylines\spacesplit{#3{##2}}}%
\parindent=0in
\advance\leftskip by \defbodyindent \advance \rightskip by \defbodyindent
\exdentamount=\defbodyindent
\begingroup\obeylines\spacesplit{#3{#5}}}

% Split up #2 at the first space token.
% call #1 with two arguments:
%  the first is all of #2 before the space token,
%  the second is all of #2 after that space token.
% If #2 contains no space token, all of it is passed as the first arg
% and the second is passed as empty.

{\obeylines
\gdef\spacesplit#1#2^^M{\endgroup\spacesplitfoo{#1}#2 \relax\spacesplitfoo}%
\long\gdef\spacesplitfoo#1#2 #3#4\spacesplitfoo{%
\ifx\relax #3%
#1{#2}{}\else #1{#2}{#3#4}\fi}}

% So much for the things common to all kinds of definitions.

% Define @defun.

% First, define the processing that is wanted for arguments of \defun
% Use this to expand the args and terminate the paragraph they make up

\def\defunargs #1{\functionparens \sl
% Expand, preventing hyphenation at `-' chars.
% Note that groups don't affect changes in \hyphenchar.
\hyphenchar\tensl=0
#1%
\hyphenchar\tensl=45
\ifnum\parencount=0 \else \errmessage{unbalanced parens in @def arguments}\fi%
\interlinepenalty=10000
\advance\rightskip by 0pt plus 1fil
\endgraf\penalty 10000\vskip -\parskip\penalty 10000%
}

\def\deftypefunargs #1{%
% Expand, preventing hyphenation at `-' chars.
% Note that groups don't affect changes in \hyphenchar.
\functionparens
\tclose{#1}% avoid \code because of side effects on active chars
\interlinepenalty=10000
\advance\rightskip by 0pt plus 1fil
\endgraf\penalty 10000\vskip -\parskip\penalty 10000%
}

% Do complete processing of one @defun or @defunx line already parsed.

% @deffn Command forward-char nchars

\def\deffn{\defmethparsebody\Edeffn\deffnx\deffnheader}

\def\deffnheader #1#2#3{\doind {fn}{\code{#2}}%
\begingroup\defname {#2}{#1}\defunargs{#3}\endgroup %
\catcode 61=\other % Turn off change made in \defparsebody
}

% @defun == @deffn Function

\def\defun{\defparsebody\Edefun\defunx\defunheader}

\def\defunheader #1#2{\doind {fn}{\code{#1}}% Make entry in function index
\begingroup\defname {#1}{Function}%
\defunargs {#2}\endgroup %
\catcode 61=\other % Turn off change made in \defparsebody
}

% @deftypefun int foobar (int @var{foo}, float @var{bar})

\def\deftypefun{\defparsebody\Edeftypefun\deftypefunx\deftypefunheader}

% #1 is the data type.  #2 is the name and args.
\def\deftypefunheader #1#2{\deftypefunheaderx{#1}#2 \relax}
% #1 is the data type, #2 the name, #3 the args.
\def\deftypefunheaderx #1#2 #3\relax{%
\doind {fn}{\code{#2}}% Make entry in function index
\begingroup\defname {\code{#1} #2}{Function}%
\deftypefunargs {#3}\endgroup %
\catcode 61=\other % Turn off change made in \defparsebody
}

% @deftypefn {Library Function} int foobar (int @var{foo}, float @var{bar})

\def\deftypefn{\defmethparsebody\Edeftypefn\deftypefnx\deftypefnheader}

% #1 is the classification.  #2 is the data type.  #3 is the name and args.
\def\deftypefnheader #1#2#3{\deftypefnheaderx{#1}{#2}#3 \relax}
% #1 is the classification, #2 the data type, #3 the name, #4 the args.
\def\deftypefnheaderx #1#2#3 #4\relax{%
\doind {fn}{\code{#3}}% Make entry in function index
\begingroup
\normalparens % notably, turn off `&' magic, which prevents
%               at least some C++ text from working
\defname {\code{#2} #3}{#1}%
\deftypefunargs {#4}\endgroup %
\catcode 61=\other % Turn off change made in \defparsebody
}

% @defmac == @deffn Macro

\def\defmac{\defparsebody\Edefmac\defmacx\defmacheader}

\def\defmacheader #1#2{\doind {fn}{\code{#1}}% Make entry in function index
\begingroup\defname {#1}{Macro}%
\defunargs {#2}\endgroup %
\catcode 61=\other % Turn off change made in \defparsebody
}

% @defspec == @deffn Special Form

\def\defspec{\defparsebody\Edefspec\defspecx\defspecheader}

\def\defspecheader #1#2{\doind {fn}{\code{#1}}% Make entry in function index
\begingroup\defname {#1}{Special Form}%
\defunargs {#2}\endgroup %
\catcode 61=\other % Turn off change made in \defparsebody
}

% This definition is run if you use @defunx
% anywhere other than immediately after a @defun or @defunx.

\def\deffnx #1 {\errmessage{@deffnx in invalid context}}
\def\defunx #1 {\errmessage{@defunx in invalid context}}
\def\defmacx #1 {\errmessage{@defmacx in invalid context}}
\def\defspecx #1 {\errmessage{@defspecx in invalid context}}
\def\deftypefnx #1 {\errmessage{@deftypefnx in invalid context}}
\def\deftypeunx #1 {\errmessage{@deftypeunx in invalid context}}

% @defmethod, and so on

% @defop {Funny Method} foo-class frobnicate argument

\def\defop #1 {\def\defoptype{#1}%
\defopparsebody\Edefop\defopx\defopheader\defoptype}

\def\defopheader #1#2#3{%
\dosubind {fn}{\code{#2}}{on #1}% Make entry in function index
\begingroup\defname {#2}{\defoptype{} on #1}%
\defunargs {#3}\endgroup %
}

% @defmethod == @defop Method

\def\defmethod{\defmethparsebody\Edefmethod\defmethodx\defmethodheader}

\def\defmethodheader #1#2#3{%
\dosubind {fn}{\code{#2}}{on #1}% entry in function index
\begingroup\defname {#2}{Method on #1}%
\defunargs {#3}\endgroup %
}

% @defcv {Class Option} foo-class foo-flag

\def\defcv #1 {\def\defcvtype{#1}%
\defopvarparsebody\Edefcv\defcvx\defcvarheader\defcvtype}

\def\defcvarheader #1#2#3{%
\dosubind {vr}{\code{#2}}{of #1}% Make entry in var index
\begingroup\defname {#2}{\defcvtype{} of #1}%
\defvarargs {#3}\endgroup %
}

% @defivar == @defcv {Instance Variable}

\def\defivar{\defvrparsebody\Edefivar\defivarx\defivarheader}

\def\defivarheader #1#2#3{%
\dosubind {vr}{\code{#2}}{of #1}% Make entry in var index
\begingroup\defname {#2}{Instance Variable of #1}%
\defvarargs {#3}\endgroup %
}

% These definitions are run if you use @defmethodx, etc.,
% anywhere other than immediately after a @defmethod, etc.

\def\defopx #1 {\errmessage{@defopx in invalid context}}
\def\defmethodx #1 {\errmessage{@defmethodx in invalid context}}
\def\defcvx #1 {\errmessage{@defcvx in invalid context}}
\def\defivarx #1 {\errmessage{@defivarx in invalid context}}

% Now @defvar

% First, define the processing that is wanted for arguments of @defvar.
% This is actually simple: just print them in roman.
% This must expand the args and terminate the paragraph they make up
\def\defvarargs #1{\normalparens #1%
\interlinepenalty=10000
\endgraf\penalty 10000\vskip -\parskip\penalty 10000}

% @defvr Counter foo-count

\def\defvr{\defvrparsebody\Edefvr\defvrx\defvrheader}

\def\defvrheader #1#2#3{\doind {vr}{\code{#2}}%
\begingroup\defname {#2}{#1}\defvarargs{#3}\endgroup}

% @defvar == @defvr Variable

\def\defvar{\defvarparsebody\Edefvar\defvarx\defvarheader}

\def\defvarheader #1#2{\doind {vr}{\code{#1}}% Make entry in var index
\begingroup\defname {#1}{Variable}%
\defvarargs {#2}\endgroup %
}

% @defopt == @defvr {User Option}

\def\defopt{\defvarparsebody\Edefopt\defoptx\defoptheader}

\def\defoptheader #1#2{\doind {vr}{\code{#1}}% Make entry in var index
\begingroup\defname {#1}{User Option}%
\defvarargs {#2}\endgroup %
}

% @deftypevar int foobar

\def\deftypevar{\defvarparsebody\Edeftypevar\deftypevarx\deftypevarheader}

% #1 is the data type.  #2 is the name.
\def\deftypevarheader #1#2{%
\doind {vr}{\code{#2}}% Make entry in variables index
\begingroup\defname {\code{#1} #2}{Variable}%
\interlinepenalty=10000
\endgraf\penalty 10000\vskip -\parskip\penalty 10000
\endgroup}

% @deftypevr {Global Flag} int enable

\def\deftypevr{\defvrparsebody\Edeftypevr\deftypevrx\deftypevrheader}

\def\deftypevrheader #1#2#3{\doind {vr}{\code{#3}}%
\begingroup\defname {\code{#2} #3}{#1}
\interlinepenalty=10000
\endgraf\penalty 10000\vskip -\parskip\penalty 10000
\endgroup}

% This definition is run if you use @defvarx
% anywhere other than immediately after a @defvar or @defvarx.

\def\defvrx #1 {\errmessage{@defvrx in invalid context}}
\def\defvarx #1 {\errmessage{@defvarx in invalid context}}
\def\defoptx #1 {\errmessage{@defoptx in invalid context}}
\def\deftypevarx #1 {\errmessage{@deftypevarx in invalid context}}
\def\deftypevrx #1 {\errmessage{@deftypevrx in invalid context}}

% Now define @deftp
% Args are printed in bold, a slight difference from @defvar.

\def\deftpargs #1{\bf \defvarargs{#1}}

% @deftp Class window height width ...

\def\deftp{\deftpparsebody\Edeftp\deftpx\deftpheader}

\def\deftpheader #1#2#3{\doind {tp}{\code{#2}}%
\begingroup\defname {#2}{#1}\deftpargs{#3}\endgroup}

% This definition is run if you use @deftpx, etc
% anywhere other than immediately after a @deftp, etc.

\def\deftpx #1 {\errmessage{@deftpx in invalid context}}

\message{cross reference,}
% Define cross-reference macros
\newwrite \auxfile

\newif\ifhavexrefs  % True if xref values are known.
\newif\ifwarnedxrefs  % True if we warned once that they aren't known.

% \setref{foo} defines a cross-reference point named foo.

\def\setref#1{%
\dosetq{#1-title}{Ytitle}%
\dosetq{#1-pg}{Ypagenumber}%
\dosetq{#1-snt}{Ysectionnumberandtype}}

\def\unnumbsetref#1{%
\dosetq{#1-title}{Ytitle}%
\dosetq{#1-pg}{Ypagenumber}%
\dosetq{#1-snt}{Ynothing}}

\def\appendixsetref#1{%
\dosetq{#1-title}{Ytitle}%
\dosetq{#1-pg}{Ypagenumber}%
\dosetq{#1-snt}{Yappendixletterandtype}}

% \xref, \pxref, and \ref generate cross-references to specified points.
% For \xrefX, #1 is the node name, #2 the name of the Info
% cross-reference, #3 the printed node name, #4 the name of the Info
% file, #5 the name of the printed manual.  All but the node name can be
% omitted.
%
\def\pxref#1{\putwordsee{} \xrefX[#1,,,,,,,]}
\def\xref#1{\putwordSee{} \xrefX[#1,,,,,,,]}
\def\ref#1{\xrefX[#1,,,,,,,]}
\def\xrefX[#1,#2,#3,#4,#5,#6]{\begingroup%
\def\printedmanual{\ignorespaces #5}%
\def\printednodename{\ignorespaces #3}%
\def\correctnodename{{\normalturnoffactive\printednodename}}%
\setbox1=\hbox{\printedmanual}%
\setbox0=\hbox{\printednodename}%
\ifdim \wd0=0pt%
% No printed node name was explicitly given.
\ifx SETxref-automatic-section-title %
% This line should make the actual chapter or section title appear inside
% the square brackets.  Use the real section title if we have it.
\ifdim \wd1>0pt%
% It is in another manual, so we don't have it.
\def\printednodename{\ignorespaces #1} \else%
% We know the real title if we have the xref values.
\ifhavexrefs \def\printednodename{\refx{#1-title}}%
% Otherwise just copy the Info node name.
\else \def\printednodename{\ignorespaces #1} \fi%
\fi\def\printednodename{#1-title}%
\else% This line just uses the node name.
\def\printednodename{\ignorespaces #1}%
\fi% ends \ifx SETxref-automatic-section-title
\fi% ends \ifdim \wd0
%
%
% If we use \unhbox0 and \unhbox1 to print the node names, TeX does
% not insert empty discretionaries after hyphens, which means that it
% will not find a line break at a hyphen in a node names.  Since some
% manuals are best written with fairly long node names, containing
% hyphens, this is a loss.  Therefore, we simply give the text of
% the node name again, so it is as if TeX is seeing it for the first
% time.
\ifdim \wd1>0pt
\putwordsection{} ``\correctnodename'' in \cite{\printedmanual}%
\else%
\turnoffactive%
\refx{#1-snt}{} [\correctnodename], \putwordpage\tie\refx{#1-pg}{}%
\fi
\endgroup}

% \dosetq is the interface for calls from other macros

% Use \turnoffactive so that punctuation chars such as underscore
% work in node names.
\def\dosetq #1#2{{\let\folio=0 \turnoffactive%
\edef\next{\write\auxfile{\internalsetq {#1}{#2}}}%
\next}}

% \internalsetq {foo}{page} expands into
% CHARACTERS 'xrdef {foo}{...expansion of \Ypage...}
% When the aux file is read, ' is the escape character

\def\internalsetq #1#2{'xrdef {#1}{\csname #2\endcsname}}

% Things to be expanded by \internalsetq

\def\Ypagenumber{\folio}

\def\Ytitle{\thissection}

\def\Ynothing{}

\def\Ysectionnumberandtype{%
\ifnum\secno=0 \putwordChapter\xreftie\the\chapno %
\else \ifnum \subsecno=0 \putwordSection\xreftie\the\chapno.\the\secno %
\else \ifnum \subsubsecno=0 %
\putwordSection\xreftie\the\chapno.\the\secno.\the\subsecno %
\else %
\putwordSection\xreftie\the\chapno.\the\secno.\the\subsecno.\the\subsubsecno %
\fi \fi \fi }

\def\Yappendixletterandtype{%
\ifnum\secno=0 \putwordAppendix\xreftie'char\the\appendixno{}%
\else \ifnum \subsecno=0 \putwordSection\xreftie'char\the\appendixno.\the\secno %
\else \ifnum \subsubsecno=0 %
\putwordSection\xreftie'char\the\appendixno.\the\secno.\the\subsecno %
\else %
\putwordSection\xreftie'char\the\appendixno.\the\secno.\the\subsecno.\the\subsubsecno %
\fi \fi \fi }

\gdef\xreftie{'tie}

% Use TeX 3.0's \inputlineno to get the line number, for better error
% messages, but if we're using an old version of TeX, don't do anything.
%
\ifx\inputlineno\thisisundefined
  \let\linenumber = \empty % Non-3.0.
\else
  \def\linenumber{\the\inputlineno:\space}
\fi

% Define \refx{NAME}{SUFFIX} to reference a cross-reference string named NAME.
% If its value is nonempty, SUFFIX is output afterward.

\def\refx#1#2{%
  \expandafter\ifx\csname X#1\endcsname\relax
    % If not defined, say something at least.
    $\langle$un\-de\-fined$\rangle$%
    \ifhavexrefs
      \message{\linenumber Undefined cross reference `#1'.}%
    \else
      \ifwarnedxrefs\else
        \global\warnedxrefstrue
        \message{Cross reference values unknown; you must run TeX again.}%
      \fi
    \fi
  \else
    % It's defined, so just use it.
    \csname X#1\endcsname
  \fi
  #2% Output the suffix in any case.
}

% Read the last existing aux file, if any.  No error if none exists.

% This is the macro invoked by entries in the aux file.
\def\xrdef #1#2{
{\catcode`\'=\other\expandafter \gdef \csname X#1\endcsname {#2}}}

\def\readauxfile{%
\begingroup
\catcode `\^^@=\other
\catcode `\
=\other
\catcode `\=\other
\catcode `\^^C=\other
\catcode `\^^D=\other
\catcode `\^^E=\other
\catcode `\^^F=\other
\catcode `\^^G=\other
\catcode `\^^H=\other
\catcode `\=\other
\catcode `\^^L=\other
\catcode `\=\other
\catcode `\=\other
\catcode `\=\other
\catcode `\=\other
\catcode `\=\other
\catcode `\=\other
\catcode `\=\other
\catcode `\=\other
\catcode `\=\other
\catcode `\=\other
\catcode `\=\other
\catcode `\=\other
\catcode 26=\other
\catcode `\^^[=\other
\catcode `\^^\=\other
\catcode `\^^]=\other
\catcode `\^^^=\other
\catcode `\^^_=\other
\catcode `\@=\other
\catcode `\^=\other
\catcode `\~=\other
\catcode `\[=\other
\catcode `\]=\other
\catcode`\"=\other
\catcode`\_=\other
\catcode`\|=\other
\catcode`\<=\other
\catcode`\>=\other
\catcode `\$=\other
\catcode `\#=\other
\catcode `\&=\other
% `\+ does not work, so use 43.
\catcode 43=\other
% the aux file uses ' as the escape.
% Turn off \ as an escape so we do not lose on
% entries which were dumped with control sequences in their names.
% For example, 'xrdef {$\leq $-fun}{page ...} made by @defun ^^
% Reference to such entries still does not work the way one would wish,
% but at least they do not bomb out when the aux file is read in.
\catcode `\{=1 \catcode `\}=2
\catcode `\%=\other
\catcode `\'=0
\catcode `\\=\other
\openin 1 \jobname.aux
\ifeof 1 \else \closein 1 \input \jobname.aux \global\havexrefstrue
\global\warnedobstrue
\fi
% Open the new aux file.  Tex will close it automatically at exit.
\openout \auxfile=\jobname.aux
\endgroup}


% Footnotes.

\newcount \footnoteno

% The trailing space in the following definition for supereject is
% vital for proper filling; pages come out unaligned when you do a
% pagealignmacro call if that space before the closing brace is
% removed.
\def\supereject{\par\penalty -20000\footnoteno =0 }

% @footnotestyle is meaningful for info output only..
\let\footnotestyle=\comment

\let\ptexfootnote=\footnote

{\catcode `\@=11
%
% Auto-number footnotes.  Otherwise like plain.
\gdef\footnote{%
  \global\advance\footnoteno by \@ne
  \edef\thisfootno{$^{\the\footnoteno}$}%
  %
  % In case the footnote comes at the end of a sentence, preserve the
  % extra spacing after we do the footnote number.
  \let\@sf\empty
  \ifhmode\edef\@sf{\spacefactor\the\spacefactor}\/\fi
  %
  % Remove inadvertent blank space before typesetting the footnote number.
  \unskip
  \thisfootno\@sf
  \footnotezzz
}%

% Don't bother with the trickery in plain.tex to not require the
% footnote text as a parameter.  Our footnotes don't need to be so general.
%
\long\gdef\footnotezzz#1{\insert\footins{%
  % We want to typeset this text as a normal paragraph, even if the
  % footnote reference occurs in (for example) a display environment.
  % So reset some parameters.
  \interlinepenalty\interfootnotelinepenalty
  \splittopskip\ht\strutbox % top baseline for broken footnotes
  \splitmaxdepth\dp\strutbox
  \floatingpenalty\@MM
  \leftskip\z@skip
  \rightskip\z@skip
  \spaceskip\z@skip
  \xspaceskip\z@skip
  \parindent\defaultparindent
  %
  % Hang the footnote text off the number.
  \hang
  \textindent{\thisfootno}%
  %
  % Don't crash into the line above the footnote text.  Since this
  % expands into a box, it must come within the paragraph, lest it
  % provide a place where TeX can split the footnote.
  \footstrut
  #1\strut}%
}

}%end \catcode `\@=11

% Set the baselineskip to #1, and the lineskip and strut size
% correspondingly.  There is no deep meaning behind these magic numbers
% used as factors; they just match (closely enough) what Knuth defined.
%
\def\lineskipfactor{.08333}
\def\strutheightpercent{.70833}
\def\strutdepthpercent {.29167}
%
\def\setleading#1{%
  \normalbaselineskip = #1\relax
  \normallineskip = \lineskipfactor\normalbaselineskip
  \normalbaselines
  \setbox\strutbox =\hbox{%
    \vrule width0pt height\strutheightpercent\baselineskip
                    depth \strutdepthpercent \baselineskip
  }%
}

% @| inserts a changebar to the left of the current line.  It should
% surround any changed text.  This approach does *not* work if the
% change spans more than two lines of output.  To handle that, we would
% have adopt a much more difficult approach (putting marks into the main
% vertical list for the beginning and end of each change).
%
\def\|{%
  % \vadjust can only be used in horizontal mode.
  \leavevmode
  %
  % Append this vertical mode material after the current line in the output.
  \vadjust{%
    % We want to insert a rule with the height and depth of the current
    % leading; that is exactly what \strutbox is supposed to record.
    \vskip-\baselineskip
    %
    % \vadjust-items are inserted at the left edge of the type.  So
    % the \llap here moves out into the left-hand margin.
    \llap{%
      %
      % For a thicker or thinner bar, change the `1pt'.
      \vrule height\baselineskip width1pt
      %
      % This is the space between the bar and the text.
      \hskip 12pt
    }%
  }%
}

% For a final copy, take out the rectangles
% that mark overfull boxes (in case you have decided
% that the text looks ok even though it passes the margin).
%
\def\finalout{\overfullrule=0pt}


% End of control word definitions.

\message{and turning on texinfo input format.}

\def\openindices{%
   \newindex{cp}%
   \newcodeindex{fn}%
   \newcodeindex{vr}%
   \newcodeindex{tp}%
   \newcodeindex{ky}%
   \newcodeindex{pg}%
}

% Set some numeric style parameters, for 8.5 x 11 format.

%\hsize = 6.5in
\newdimen\defaultparindent \defaultparindent = 15pt
\parindent = \defaultparindent
\parskip 3pt plus2pt minus2pt
\setleading{13pt}
\advance\topskip by 1.2cm

% Prevent underfull vbox error messages.
\vbadness=10000
\hbadness=3000

% Following George Bush, just get rid of widows and orphans.
\widowpenalty=10000
\clubpenalty=10000

% Use TeX 3.0's \emergencystretch to help line breaking, but if we're
% using an old version of TeX, don't do anything.  We want the amount of
% stretch added to depend on the line length, hence the dependence on
% \hsize.  This makes it come to about 9pt for the 8.5x11 format.
%
\ifx\emergencystretch\thisisundefined
  % Allow us to assign to \emergencystretch anyway.
  \def\emergencystretch{\dimen0}%
\else
  \emergencystretch = \hsize
  \divide\emergencystretch by 45
\fi

% Use @smallbook to reset parameters for 7x9.5 format  (or else 7x9.25)
\def\smallbook{

% These values for secheadingskip and subsecheadingskip are
% experiments.  RJC 7 Aug 1992
\global\secheadingskip = 17pt plus 6pt minus 3pt
\global\subsecheadingskip = 14pt plus 6pt minus 3pt

\global\lispnarrowing = 0.3in
\setleading{12pt}
\advance\topskip by -1cm
\global\parskip 3pt plus 1pt
\global\hsize = 5in
\global\vsize=7.5in
\global\tolerance=700
\global\hfuzz=1pt
\global\contentsrightmargin=0pt
\global\deftypemargin=0pt
\global\defbodyindent=.5cm

\global\pagewidth=\hsize
\global\pageheight=\vsize

\global\let\smalllisp=\smalllispx
\global\let\smallexample=\smalllispx
\global\def\Esmallexample{\Esmalllisp}
}

% Use @afourpaper to print on European A4 paper.
\def\afourpaper{
\global\tolerance=700
\global\hfuzz=1pt
\setleading{12pt}
\global\parskip 15pt plus 1pt

\global\vsize= 53\baselineskip
\advance\vsize by \topskip
%\global\hsize=   5.85in     % A4 wide 10pt
\global\hsize=  6.5in
\global\outerhsize=\hsize
\global\advance\outerhsize by 0.5in
\global\outervsize=\vsize
\global\advance\outervsize by 0.6in

\global\pagewidth=\hsize
\global\pageheight=\vsize
}

% Define macros to output various characters with catcode for normal text.
\catcode`\"=\other
\catcode`\~=\other
\catcode`\^=\other
\catcode`\_=\other
\catcode`\|=\other
\catcode`\<=\other
\catcode`\>=\other
\catcode`\+=\other
\def\normaldoublequote{"}
\def\normaltilde{~}
\def\normalcaret{^}
\def\normalunderscore{_}
\def\normalverticalbar{|}
\def\normalless{<}
\def\normalgreater{>}
\def\normalplus{+}

% This macro is used to make a character print one way in ttfont
% where it can probably just be output, and another way in other fonts,
% where something hairier probably needs to be done.
%
% #1 is what to print if we are indeed using \tt; #2 is what to print
% otherwise.  Since all the Computer Modern typewriter fonts have zero
% interword stretch (and shrink), and it is reasonable to expect all
% typewriter fonts to have this, we can check that font parameter.
%
\def\ifusingtt#1#2{\ifdim \fontdimen3\the\font=0pt #1\else #2\fi}

% Turn off all special characters except @
% (and those which the user can use as if they were ordinary).
% Most of these we simply print from the \tt font, but for some, we can
% use math or other variants that look better in normal text.

\catcode`\"=\active
\def\activedoublequote{{\tt \char '042}}
\let"=\activedoublequote
\catcode`\~=\active
\def~{{\tt \char '176}}
\chardef\hat=`\^
\catcode`\^=\active
\def^{{\tt \hat}}

\catcode`\_=\active
\def_{\ifusingtt\normalunderscore\_}
% Subroutine for the previous macro.
\def\_{\lvvmode \kern.06em \vbox{\hrule width.3em height.1ex}}

% \lvvmode is equivalent in function to \leavevmode.
% Using \leavevmode runs into trouble when written out to
% an index file due to the expansion of \leavevmode into ``\unhbox
% \voidb@x'' ---which looks to TeX like ``\unhbox \voidb\x'' due to our
% magic tricks with @.
\def\lvvmode{\vbox to 0pt{}}

\catcode`\|=\active
\def|{{\tt \char '174}}
\chardef \less=`\<
\catcode`\<=\active
\def<{{\tt \less}}
\chardef \gtr=`\>
\catcode`\>=\active
\def>{{\tt \gtr}}
\catcode`\+=\active
\def+{{\tt \char 43}}
%\catcode 27=\active
%\def^^[{$\diamondsuit$}

% Set up an active definition for =, but don't enable it most of the time.
{\catcode`\==\active
\global\def={{\tt \char 61}}}

\catcode`\@=0

% \rawbackslashxx output one backslash character in current font
\global\chardef\rawbackslashxx=`\\
%{\catcode`\\=\other
%@gdef@rawbackslashxx{\}}

% \rawbackslash redefines \ as input to do \rawbackslashxx.
{\catcode`\\=\active
@gdef@rawbackslash{@let\=@rawbackslashxx }}

% \normalbackslash outputs one backslash in fixed width font.
\def\normalbackslash{{\tt\rawbackslashxx}}

% Say @foo, not \foo, in error messages.
\escapechar=`\@

% \catcode 17=0   % Define control-q
\catcode`\\=\active

% Used sometimes to turn off (effectively) the active characters
% even after parsing them.
@def@turnoffactive{@let"=@normaldoublequote
@let\=@realbackslash
@let~=@normaltilde
@let^=@normalcaret
@let_=@normalunderscore
@let|=@normalverticalbar
@let<=@normalless
@let>=@normalgreater
@let+=@normalplus}

@def@normalturnoffactive{@let"=@normaldoublequote
@let\=@normalbackslash
@let~=@normaltilde
@let^=@normalcaret
@let_=@normalunderscore
@let|=@normalverticalbar
@let<=@normalless
@let>=@normalgreater
@let+=@normalplus}

% If a .fmt file is being used, we don't want the `\input texinfo' to show up.
% That is what \eatinput is for; after that, the `\' should revert to printing
% a backslash.
%
@gdef@eatinput input texinfo{@fixbackslash}
@global@let\ = @eatinput

% On the other hand, perhaps the file did not have a `\input texinfo'. Then
% the first `\{ in the file would cause an error. This macro tries to fix
% that, assuming it is called before the first `\' could plausibly occur.
%
@gdef@fixbackslash{@ifx\@eatinput @let\ = @normalbackslash @fi}

%% These look ok in all fonts, so just make them not special.  The @rm below
%% makes sure that the current font starts out as the newly loaded cmr10
@catcode`@$=@other @catcode`@%=@other @catcode`@&=@other @catcode`@#=@other

@textfonts
@rm

@c Local variables:
@c page-delimiter: "^\\\\message"
@c TeX-master: t
@c End: