ltfiles.dtx
% \iffalse meta-comment
%
% Copyright (C) 1993-2024
% The LaTeX Project and any individual authors listed elsewhere
% in this file.
%
% This file is part of the LaTeX base system.
% -------------------------------------------
%
% It may be distributed and/or modified under the
% conditions of the LaTeX Project Public License, either version 1.3c
% of this license or (at your option) any later version.
% The latest version of this license is in
% https://www.latex-project.org/lppl.txt
% and version 1.3c or later is part of all distributions of LaTeX
% version 2008 or later.
%
% This file has the LPPL maintenance status "maintained".
%
% The list of all files belonging to the LaTeX base distribution is
% given in the file `manifest.txt'. See also `legal.txt' for additional
% information.
%
% The list of derived (unpacked) files belonging to the distribution
% and covered by LPPL is defined by the unpacking scripts (with
% extension .ins) which are part of the distribution.
%
% \fi
%
% \iffalse
%%% From File: ltfiles.dtx
%<*driver>
% \fi
\ProvidesFile{ltfiles.dtx}
[2023/06/17 v1.2u LaTeX Kernel (File Handling)]
% \iffalse
\documentclass{ltxdoc}
\GetFileInfo{ltfiles.dtx}
\title{\filename}
\date{\filedate}
\author{%
Johannes Braams\and
David Carlisle\and
Alan Jeffrey\and
Leslie Lamport\and
Frank Mittelbach\and
Chris Rowley\and
Rainer Sch\"opf}
\providecommand\pkg[1]{\texttt{#1}}
\providecommand\InternalDetectionOff{}
\providecommand\InternalDetectionOn{}
\begin{document}
\MaintainedByLaTeXTeam{latex}
\maketitle
\DocInput{\filename}
\end{document}
%</driver>
% \fi
%
% \providecommand\hook[1]{\texttt{#1}}
%
%
% \changes{v1.0h}{1994/05/21}{Use new error commands}
% \changes{v1.0n}{1994/11/17}
% {\cs{@tempa} to \cs{reserved@a}}
% \changes{v1.0u}{1995/07/13}{Updates to docu}
% \changes{v1.1m}{2015/02/21}
% {Removed autoload support}
% \changes{v1.2i}{2020/08/21}{Integration of new hook management interface}
%
% \section{File Handling}
%
% The following user commands are defined in this part:
%
% \DescribeMacro{\document} (ie |\begin{document}|)\\
% Reads in the .AUX files and |\catcode|'s |@| to 12.
%
% \DescribeMacro{\nofiles}\\
% Suppresses all file output by setting |\@filesw| false.
%
% \DescribeMacro{\includeonly}\marg{NAME1, ... ,NAMEn}\\
% Causes only parts NAME1, ... ,NAMEn to be read by
% their |\include| commands. Works by setting \@partsw true
% and setting |\@partlist| to NAME1, ... ,NAMEn.
%
% \DescribeMacro{\include}\marg{NAME}\\
% Does an |\input| NAME unless |\@partsw| is true and
% NAME is not in |\@partlist|. If |\@filesw| is true, then
% it directs .AUX output to NAME.AUX, including a
% checkpoint at the end.
%
% \DescribeMacro{\input}\marg{NAME}\\
% The same as TeX's |\input|, except it allows optional
% braces around the file name. In \LaTeXe, it also avoids
% the primitive `missing file' error, if the file can not be
% found.
%
% \DescribeMacro{\IfFileExists}\marg{NAME}\marg{then}\marg{else}\\
% If the file exists on the system, execute \emph{then} otherwise
% execute \emph{else}.
%
% \DescribeMacro{\InputIfFileExists}\marg{NAME}\marg{then}\marg{else}\\
% If the file exists on the system, execute \emph{then} and input
% \emph{NAME} otherwise execute \emph{else}.
%
% \MaybeStop{}
%
% \changes{v1.0a}{1994/03/07}{Initial version, split from latex.dtx}
% \changes{v1.0a}{1994/03/07}{Long lines wrapped to 72 columns}
%
% \begin{oldcomments}
%
% \begin{macrocode}
%<*2ekernel>
\message{files,}
% \end{macrocode}
%
% VARIABLES, SWITCHES AND INTERNAL COMMANDS:
% \@mainaux : Output file number for main .AUX file.
% \@partaux : Output file number for current part's .AUX file.
% \@auxout : Either \@mainout or \@partout, depending on
% which .AUX file output goes to.
% \@input{foo} : If file foo exists, then \input's it,
% otherwise types a warning message.
% @filesw : Switch -- set false if no .AUX, .TOC, .IDX etc
% files are to be written
% @partsw : Set true by a \includeonly command.
% \@partlist : Set to the argument of the \includeonly command.
%
% \cp@FOO : The checkpoint for \include'd file FOO.TEX, written
% by \@writeckpt at the end of file FOO.AUX
%
%
% \includeonly{FILELIST} ==
% BEGIN
% \@partsw := T
% \@partlist := FILELIST
% END
%
% \include{FILE} ==
% BEGIN
% \clearpage
% if \@filesw = T
% then \immediate\write\@mainaux{\string\@input{FILE.AUX}}
% fi
% if \@partsw = T
% then \@tempswa := F
% \reserved@b == FILE
% for \reserved@a := \@partlist
% do if eval(\reserved@a) = eval(\reserved@b)
% then \@tempswa := T fi
% od
% fi
%
% if \@tempswa = T
% then \@auxout := \@partaux
% if \@filesw = T
% then \immediate\openout\@partaux{FILE.AUX}
% \immediate\write\@partaux{\relax}
% fi
% \@input{FILE.TEX}
% \clearpage
% \@writeckpt{FILE}
% if @filesw then \closeout \@partaux fi
% \@auxout := \@mainaux
% else \cp@FILE
% fi
% END
%
% \@writeckpt{FILE} ==
% BEGIN
% if \@filesw = T
% \immediate\write on file \@partaux:
% \@setckpt{FILE}{ %% }
% for \reserved@a := \cl@@ckpt
% do \immediate\write on file \@partaux:
% \global\string\setcounter
% {eval(\reserved@a)}{eval(\c@eval(\reserved@a))}
% od %% {
% \immediate\write on file \@partaux: }
% fi
% END
%
% \@setckpt{FILE}{LIST} ==
% BEGIN
% G \cp@FILE := LIST
% END
%
% INITIALIZATION
% \@tempswa := T
%
% \end{oldcomments}
%
%
% \begin{macro}{\@mainaux}
% \begin{macro}{\@partaux}
% \begin{macrocode}
\newwrite\@mainaux
\newwrite\@partaux
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\if@filesw}
% \begin{macro}{\if@partsw}
% \begin{macrocode}
\newif\if@filesw \@fileswtrue
\newif\if@partsw \@partswfalse
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\@clubpenalty}
% This stores the current normal (non-infinite) value of
% \cs{clubpenalty}; it should therefore be reset whenever the
% normal value is changed (as in the bibliography in the standard
% styles).
% \changes{v1.1h}{1996/10/05}{Added setting its value}
% \begin{macrocode}
\newcount\@clubpenalty
\@clubpenalty \clubpenalty
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\document}
% \changes{v0.9e}{1993/12/09}{Hook added}
% \begin{macrocode}
%</2ekernel>
%<latexrelease>\IncludeInRelease{2020/10/01}%
%<latexrelease> {\document}{Added hook to load l3backend code}%
%<*2ekernel|latexrelease>
\def\document{%
% \end{macrocode}
% We do cancel the grouping as part of the \cs{begin} handling
% (this is now done inside \cs{begin} instead) so that the
% \hook{env/\meta{env}/begin} hook is not hidden inside \cs{begingroup}
% \texttt{...} \cs{endgroup}.
% \begin{macrocode}
% \endgroup
% \end{macrocode}
%
% \begin{macrocode}
\UseOneTimeHook{begindocument/before}%
\@kernel@after@begindocument@before
% \end{macrocode}
%
% Added hook to load \textsf{l3backend} code:
% \changes{v1.2h}{2020/06/05}{Added hook to load \textsf{l3backend} code}
% \begin{macrocode}
\@expl@sys@load@backend@@
\ifx\@unusedoptionlist\@empty\else
\@latex@warning@no@line{Unused global option(s):^^J%
\@spaces[\@unusedoptionlist]}%
\fi
\@colht\textheight
\@colroom\textheight \vsize\textheight
\columnwidth\textwidth
\@clubpenalty\clubpenalty
\if@twocolumn
\advance\columnwidth -\columnsep
\divide\columnwidth\tw@ \hsize\columnwidth \@firstcolumntrue
\fi
\hsize\columnwidth \linewidth\hsize
\begingroup\@floatplacement\@dblfloatplacement
\makeatletter\let\@writefile\@gobbletwo
% \end{macrocode}
% \changes{v1.1a}{1995/10/24}
% {Removed multiplelabels switch}
% \begin{macrocode}
\global \let \@multiplelabels \relax
\@input{\jobname.aux}%
\endgroup
\if@filesw
\immediate\openout\@mainaux\jobname.aux
\immediate\write\@mainaux{\relax}%
\fi
% \end{macrocode}
%
% Dateline 1991/03/26: FMi added |\process@table| to support NFSS;
% This will also work with old lfonts if no other style defines
% |\process@table|. The following line forces the initialization of
% the math fonts.
% \begin{macrocode}
\process@table
\let\glb@currsize\@empty % Force math initialization.
% \end{macrocode}
% \changes{v0.9t}{1994/01/31}
% {set \cs{@normalsize} or \cs{normalsize} if necessary}
% \changes{v1.0d}{1994/03/28}
% {(DPC) remove \cs{@normalsize check}}
% \changes{v1.0d}{1994/03/28}
% {(DPC) Use \cs{normalsize} not \cs{@normalsize}}
% \changes{v1.0g}{1994/05/13}{Added execution of \cs{every@size}}
% \changes{v1.0m}{1994/11/07}{Renamed \cs{every@size} to
% \cs{every@math@size}.}
% \changes{v1.0q}{1995/04/25}
% {Removed execution of \cs{every@size} latex/1407}
% \begin{macrocode}
\normalsize
\everypar{}%
% \end{macrocode}
%
% So that punctuation in headings is not disturbed by verbatim
% or other local changes to the space factor codes, save the document
% default here. This will be locally reset by the output routine.
% For special cases a class may want to define |\normalsfcodes|
% directly, in case that definition will be used.
% (This is an old bug, problem existed in \LaTeX2.0x and plain \TeX.)
% \changes{v1.1k}{1997/04/14}
% {Set the document space factor defaults. latex/2404}
% \begin{macrocode}
\ifx\normalsfcodes\@empty
\ifnum\sfcode`\.=\@m
\let\normalsfcodes\frenchspacing
\else
\let\normalsfcodes\nonfrenchspacing
\fi
\fi
% \end{macrocode}
% For similar reasons also save the default language, this will be reset
% locally in the output routine. In particular it allows hyphenation
% in the page head even if the page break happens in verbatim.
% If this has already been set by a package, set to the value of |\language|
% at this point.
% \changes{v1.1n}{2017/03/10}{Save language default}
% \begin{macrocode}
\ifx\document@default@language\m@ne
\chardef\document@default@language\language
\fi
% \end{macrocode}
%
% Way back in 1991 (08/26) FMi \& RmS set the |\@noskipsec| switch
% to true in the preamble and to false here.
% This was done to trap lists and related text in the preamble but it
% does not catch everything; hence Change 1.1g was introduced.
% \begin{macrocode}
\@noskipsecfalse
% \end{macrocode}
% \changes{v1.1a}{1995/10/24}
% {Removed refundefined switch}
% \begin{macrocode}
\let \@refundefined \relax
% \end{macrocode}
% Just before disabling the preamble commands we execute the begin
% document hook which contains any code contributed by
% |\AtBeginDocument|. Also disable the gathering of the file list,
% if no |\listfiles| has been issued. |\AtBeginDocument| is redefined
% at this point so that and such commands that get into the hook do
% not chase their tail\ldots
% \changes{v1.1e}{1996/04/24}
% {(DPC) Reset \cs{AtBeginDocument} eg for latex/1297}
% \begin{macrocode}
\@kernel@before@begindocument
\UseOneTimeHook{begindocument}%
\@kernel@after@begindocument
% \end{macrocode}
%
% Most of the following assignments will be done globally in case
% the user adds something like |\begin{multicols}| to the document
% hook, i.e. starts are group in |\begin{document}|.
% \changes{v1.0r}{1995/04/27}
% {Added \cs{global} to support groups in hook}
% \changes{v1.0c}{1994/03/16}
% {(DPC) directly add file list settings}
% \changes{v1.0v}{1995/08/16}{set \cs{topskip} globally}
% \changes{v1.0v}{1995/08/16}{set \cs{@maxdepth}}
%
% \changes{v1.0s}{1995/05/25}
% {Added check for \cs{topskip} zero}
% \changes{v1.0t}{1995/05/25}
% {Corrected typo}
% Since a value of exactly 0pt for \cs{topskip} causes
% \cs{twocolumn[]} to misbehave, we add this check, hoping
% that it will not cause any problems elsewhere.
% \begin{macrocode}
\ifdim\topskip<1sp\global\topskip 1sp\relax\fi
\global\@maxdepth\maxdepth
\global\let\@begindocumenthook\@undefined
\ifx\@listfiles\@undefined
\global\let\@filelist\relax
\global\let\@addtofilelist\@gobble
\fi
% \end{macrocode}
% At the very end we disable all preamble commands. This has to
% happen after the begin document hooks was executed so that this
% hook can still use such commands.
% \changes{v0.9o}{1994/01/15}
% {move \cs{@preamblecmds} after document hook}
% \changes{v1.0v}{1995/08/16}{set \cs{do} globally}
% \begin{macrocode}
\gdef\do##1{\global\let ##1\@notprerr}%
\@preamblecmds
% \end{macrocode}
% The next line saves tokens and also allows |\@nodocument| to be
% used directly to trap preamble errors.
% \changes{v1.1g}{1996/09/29}{Added disabling of \cs{@nodocument}}
% \begin{macrocode}
\global\let \@nodocument \relax
% \end{macrocode}
% The next line is a pure safety measure in case a do list is ever
% expanded at the wrong place. In addition it will save a few
% tokens to get rid of the above definition.
% \begin{macrocode}
\global\let\do\noexpand
% \end{macrocode}
%
% \begin{macrocode}
\UseOneTimeHook{begindocument/end}%
% \end{macrocode}
% \changes{v1.1c}{1995/12/05}{\cs{ignorespaces} added for latex/1933}
% Use of the hook might mean that we are already in
% horizontal mode, so ignore the space after |\begin{document}|.
% \begin{macrocode}
\ignorespaces}
% \end{macrocode}
%
% Provide a global definition for \cs{do} as well, so that it is
% already defined in the preamble and not late as
% \verb=\begin{document}= overwriting some definition given by the
% unsuspecting user in the preamble.
% \changes{v1.2s}{2023/01/05}{\cs{do} now with default definition in
% the kernel (gh/975)}
% \begin{macrocode}
\let\do\noexpand
% \end{macrocode}
%
% The \hook{begindocument} hook already existed in the kernel since
% 1994 under the name \cs{atbegindocumenthook} the
% additional ones are originally from the \pkg{etoolbox}
% package under the names \cs{@endpreamblehook} \cs{afterpreamble}.
% \begin{macrocode}
\NewHook{begindocument}
\NewHook{begindocument/before}
\NewHook{begindocument/end}
% \end{macrocode}
% \begin{macro}{\@kernel@after@begindocument@before,
% \@kernel@before@begindocument,
% \@kernel@after@begindocument}
%
% Above we used two kernel only hooks to be run after the public
% \hook{begindocument/before} and after \hook{begindocument}
% hooks.
%
% In \cs{@kernel@after@begindocument@before} we already place one
% action: drop the fast execution code for the
% \hook{env/document/begin} hook. That hook marks the end of the
% preamble and should therefore only be run once. In a normal
% document that is anyway the case (so the code would just sit
% there taking up space afterwards, which these days is rather
% harmless), however, in more complicated scenarios where several
% full documents are combined to a single document it might get
% applied several times with harmful effects. We therefore
% explicitly drop it at this point. the coding is somewhat obscure
% due to the name of the macro which requires constructing.
% \InternalDetectionOff
% \begin{macrocode}
\edef \@kernel@after@begindocument@before {%
\let\expandafter\noexpand\csname
__hook env/document/begin\endcsname
\noexpand\@empty}
% \end{macrocode}
% \InternalDetectionOn
%
% These internal hooks are already declared earlier (in
% \texttt{ltexpl}) so that other modules could write to them.
% \changes{v1.2m}{2021/04/17}{Move \cs{@kernel@before@begindocument} and
% \cs{@kernel@after@begindocument} init earlier so that other modules can
% write to the hooks}
% \begin{macrocode}
%\let \@kernel@before@begindocument \@empty
%\let \@kernel@after@begindocument \@empty
% \end{macrocode}
%
% \end{macro}
%
%
% \begin{macrocode}
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
% \end{macrocode}
%
% \begin{macrocode}
%<latexrelease>\IncludeInRelease{2017/04/15}%
%<latexrelease> {\document}{Save language for hyphenation}%
%<latexrelease>
%<latexrelease>\def\document{\endgroup
%<latexrelease> \ifx\@unusedoptionlist\@empty\else
%<latexrelease> \@latex@warning@no@line{Unused global option(s):^^J%
%<latexrelease> \@spaces[\@unusedoptionlist]}%
%<latexrelease> \fi
%<latexrelease> \@colht\textheight
%<latexrelease> \@colroom\textheight \vsize\textheight
%<latexrelease> \columnwidth\textwidth
%<latexrelease> \@clubpenalty\clubpenalty
%<latexrelease> \if@twocolumn
%<latexrelease> \advance\columnwidth -\columnsep
%<latexrelease> \divide\columnwidth\tw@ \hsize\columnwidth \@firstcolumntrue
%<latexrelease> \fi
%<latexrelease> \hsize\columnwidth \linewidth\hsize
%<latexrelease> \begingroup\@floatplacement\@dblfloatplacement
%<latexrelease> \makeatletter\let\@writefile\@gobbletwo
%<latexrelease> \global \let \@multiplelabels \relax
%<latexrelease> \@input{\jobname.aux}%
%<latexrelease> \endgroup
%<latexrelease> \if@filesw
%<latexrelease> \immediate\openout\@mainaux\jobname.aux
%<latexrelease> \immediate\write\@mainaux{\relax}%
%<latexrelease> \fi
%<latexrelease> \process@table
%<latexrelease> \let\glb@currsize\@empty % Force math initialization.
%<latexrelease> \normalsize
%<latexrelease> \everypar{}%
%<latexrelease> \ifx\normalsfcodes\@empty
%<latexrelease> \ifnum\sfcode`\.=\@m
%<latexrelease> \let\normalsfcodes\frenchspacing
%<latexrelease> \else
%<latexrelease> \let\normalsfcodes\nonfrenchspacing
%<latexrelease> \fi
%<latexrelease> \fi
%<latexrelease> \ifx\document@default@language\m@ne
%<latexrelease> \chardef\document@default@language\language
%<latexrelease> \fi
%<latexrelease> \@noskipsecfalse
%<latexrelease> \let \@refundefined \relax
%<latexrelease> \let\AtBeginDocument\@firstofone
%<latexrelease> \@begindocumenthook
%<latexrelease> \ifdim\topskip<1sp\global\topskip 1sp\relax\fi
%<latexrelease> \global\@maxdepth\maxdepth
%<latexrelease> \global\let\@begindocumenthook\@undefined
%<latexrelease> \ifx\@listfiles\@undefined
%<latexrelease> \global\let\@filelist\relax
%<latexrelease> \global\let\@addtofilelist\@gobble
%<latexrelease> \fi
%<latexrelease> \gdef\do##1{\global\let ##1\@notprerr}%
%<latexrelease> \@preamblecmds
%<latexrelease> \global\let \@nodocument \relax
%<latexrelease> \global\let\do\noexpand
%<latexrelease> \ignorespaces}
%<latexrelease>\EndIncludeInRelease
%<latexrelease>
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\document}{Save language for hyphenation}
%<latexrelease>\def\document{\endgroup
%<latexrelease> \ifx\@unusedoptionlist\@empty\else
%<latexrelease> \@latex@warning@no@line{Unused global option(s):^^J%
%<latexrelease> \@spaces[\@unusedoptionlist]}%
%<latexrelease> \fi
%<latexrelease> \@colht\textheight
%<latexrelease> \@colroom\textheight \vsize\textheight
%<latexrelease> \columnwidth\textwidth
%<latexrelease> \@clubpenalty\clubpenalty
%<latexrelease> \if@twocolumn
%<latexrelease> \advance\columnwidth -\columnsep
%<latexrelease> \divide\columnwidth\tw@ \hsize\columnwidth
%<latexrelease> \@firstcolumntrue
%<latexrelease> \fi
%<latexrelease> \hsize\columnwidth \linewidth\hsize
%<latexrelease> \begingroup\@floatplacement\@dblfloatplacement
%<latexrelease> \makeatletter\let\@writefile\@gobbletwo
%<latexrelease> \global \let \@multiplelabels \relax
%<latexrelease> \@input{\jobname.aux}%
%<latexrelease> \endgroup
%<latexrelease> \if@filesw
%<latexrelease> \immediate\openout\@mainaux\jobname.aux
%<latexrelease> \immediate\write\@mainaux{\relax}%
%<latexrelease> \fi
%<latexrelease> \process@table
%<latexrelease> \let\glb@currsize\@empty
%<latexrelease> \normalsize
%<latexrelease> \everypar{}%
%<latexrelease> \ifx\normalsfcodes\@empty
%<latexrelease> \ifnum\sfcode`\.=\@m
%<latexrelease> \let\normalsfcodes\frenchspacing
%<latexrelease> \else
%<latexrelease> \let\normalsfcodes\nonfrenchspacing
%<latexrelease> \fi
%<latexrelease> \fi
%<latexrelease> \@noskipsecfalse
%<latexrelease> \let \@refundefined \relax
%<latexrelease> \let\AtBeginDocument\@firstofone
%<latexrelease> \@begindocumenthook
%<latexrelease> \ifdim\topskip<1sp\global\topskip 1sp\relax\fi
%<latexrelease> \global\@maxdepth\maxdepth
%<latexrelease> \global\let\@begindocumenthook\@undefined
%<latexrelease> \ifx\@listfiles\@undefined
%<latexrelease> \global\let\@filelist\relax
%<latexrelease> \global\let\@addtofilelist\@gobble
%<latexrelease> \fi
%<latexrelease> \gdef\do##1{\global\let ##1\@notprerr}%
%<latexrelease> \@preamblecmds
%<latexrelease> \global\let \@nodocument \relax
%<latexrelease> \global\let\do\noexpand
%<latexrelease> \ignorespaces}
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
%
% \begin{macrocode}
\@onlypreamble\document
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\normalsfcodes}
% \changes{v1.1k}{1997/04/14}
% {Macro added (from patch file) latex/2404}
% The setting of |\@empty| is just a flag. This command may be defined
% in a class or package file. If it is still |\@empty| at
% |\begin{document}| it will be defined to be |\frenchspacing| or
% |\nonfrenchspacing|, depending on which of those appears to be in
% effect at that point.
% \begin{macrocode}
\let\normalsfcodes\@empty
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\nofiles}
% \changes{v1.0k}{1994/11/04}
% {Added setting of \cs{protected@write},
% \cs{makeindex} and \cs{makeglossary} to \cs{nofiles}. ASAJ.}
% \changes{v1.0o}{1994/11/30}
% {There is no \cs{@gobblethree}\ldots}
% \changes{v1.0t}{1995/05/25}
% {(CAR) added \cs{long}}
% \changes{v1.1f}{1996/05/17}
% {added \cs{write} to \cs{protected@write} for latex/2146}
% Set |\@fileswfalse| which suppresses the places where \LaTeX\ makes
% |\immediate| writes. The |\makeindex| and |\makeglossary| are
% disabled. |\protected@write| is redefined not to write to the file
% specified, but rather to write a blank line to the log file. This
% ensures that a \meta{whatsit} node is still created, and so spacing
% is not affected by the |\nofiles| command; to ensure this more
% generally, the |\if@nobreak| test is needed.
% \changes{v1.1i}{1996/11/05}
% {Standard \cs{if@nobreak} test added}
% \begin{macrocode}
\def\nofiles{%
\@fileswfalse
\typeout{No auxiliary output files.^^J}%
\long\def\protected@write##1##2##3%
{\write\m@ne{}\if@nobreak\ifvmode\nobreak\fi\fi}%
\let\makeindex\relax
\let\makeglossary\relax}
\@onlypreamble\nofiles
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\protected@write}
% This takes three arguments: an output stream, some initialization
% code, and some text to write. It then writes this, with
% appropriate handling of |\protect| and |\thepage|.
% \changes{v1.0k}{1994/11/04}{Macro added ASAJ.}
% \changes{v1.0t}{1995/05/25}
% {(CAR) added \cs{long}}
% \begin{macrocode}
\long\def \protected@write#1#2#3{%
\begingroup
\let\thepage\relax
#2%
\let\protect\@unexpandable@protect
\edef\reserved@a{\write#1{#3}}%
\reserved@a
\endgroup
\if@nobreak\ifvmode\nobreak\fi\fi
}
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
\let\@auxout=\@mainaux
% \end{macrocode}
%
%
% \begin{macro}{\include,\includeonly}
% \changes{v0.9p}{1994/01/18}
% {Use \cs{@input@} so include files are listed.}
% \changes{v1.0p}{1995/04/22}{Allow blanks in argument}
% \changes{v1.2a}{2019/07/01}{Support UTF-8}
% \changes{v1.2g}{2020/05/02}{Improved support for spaces in filenames
% (gh/217)}
%
% In the definition of |\include|, |\def\reserved@b| changed to
% |\edef\reserved@b| to be consistent with the |\edef| in
% |\includeonly|.
% (Suggested by Rainer Sch\"opf \& Frank Mittelbach.
% Change made 20 Jul 88.)
%
% Changed definition of |\include| to allow space at end of file name
% --- otherwise, typing |\include{foo }| would cause \LaTeX\ to
% overwrite |foo.tex|. Change made 24 May 89, suggested by Rainer
% Sch\"opf and Frank Mittelbach
%
% Made |\include| check for being used inside an |\include|'d file, as
% this will not work and cause surprising results.
% \changes{v1.2g}{2020/05/02}{Get rid of leading and trailing spaces
% from the filename (gh/217)}
% \changes{v1.2g}{2020-05-02}{Pass the filename to \cs{@include} by
% value instead of by reference (gh/217)}
%
% \begin{macrocode}
%</2ekernel>
%<*2ekernel|latexrelease>
%<latexrelease>\IncludeInRelease{2020/10/01}%
%<latexrelease> {\includeonly}{Spaces in file names}%
% \end{macrocode}
%
% \begin{macrocode}
\def\include#1{\relax
\ifnum\@auxout=\@partaux
\@latex@error{\string\include\space cannot be nested}\@eha
\else
% \end{macrocode}
% Here the normalization will add |.tex| for all files, (it uses
% the same normalization as the hooks), so we need to remove that
% manually. \cs{@strip@tex@ext} does that.
% \begin{macrocode}
\set@curr@file{#1}%
\edef\@curr@file{\@strip@tex@ext\@curr@file}%
% \end{macrocode}
% For historical reasons \cs{@include} expects an argument
% delimited by a space. This is kept (though unnecessary now) to avoid
% errors in other packages that use \cs{@include} directly.
% \begin{macrocode}
\expandafter\@include\expandafter{\@curr@file} % deliberate space
\fi}
% \end{macrocode}
%
% Here in \cs{includeonly} we also need to strip |.tex| after
% normalization:
% \begin{macrocode}
\def\includeonly#1{%
\@partswtrue
% \end{macrocode}
% Because the argument to |\includeonly| is a comma-separated list
% of filenames where there may be comma's preceding some of the
% filenames or trailing them. Therefore we need to take the list
% apart, remove the unwanted spaces while leaving the spaces
% \emph{in} the filenames intact.
% \begin{macrocode}
\let\@partlist\@empty
\@for\reserved@a:=#1 \do
{%
\expandafter\set@curr@file\expandafter{\reserved@a}%
\ifx\@partlist\@empty
\edef\@partlist{\@strip@tex@ext\@curr@file}%
\else
\edef\@partlist{\@partlist,\@strip@tex@ext\@curr@file}%
\fi
}%
}
\@onlypreamble\includeonly
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@strip@tex@ext,\@strip@tex@ext@aux}
% These macros take a (\cs{detokenize}d file name and remove any
% |.tex| extension). Extra care is taken to not remove the string
% |.tex| from the middle of a file name: it is only removed if it's
% the very last thing in the file name.
% \begin{macrocode}
\def\reserved@a#1{%
\def\@strip@tex@ext##1{%
\expandafter\@strip@tex@ext@aux
##1\@nil\@nil
#1\@nil\relax\@nnil}
\def\@strip@tex@ext@aux##1#1\@nil##2\@nnil{%
\ifx\relax##2\@empty
\expandafter\@cdr\expandafter\@empty\@cdr{}##1%
\else##1\fi}}%
\expandafter\reserved@a
\expandafter{\detokenize{.tex}}
%</2ekernel|latexrelease>
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{2019/10/01}%
%<latexrelease> {\includeonly}{Spaces in file names}%
%<latexrelease>
%<latexrelease>\def\includeonly#1{%
%<latexrelease> \@partswtrue
%<latexrelease> \set@curr@file{\zap@space#1 \@empty}%
%<latexrelease> \let\@partlist\@curr@file
%<latexrelease> }
%<latexrelease>
%<latexrelease>\def\include#1{\relax
%<latexrelease> \ifnum\@auxout=\@partaux
%<latexrelease> \@latex@error{\string\include\space cannot be nested}\@eha
%<latexrelease> \else
%<latexrelease> \set@curr@file{#1 }%
%<latexrelease> \expandafter\@include\@curr@file
%<latexrelease> \fi}
%<latexrelease>
%<latexrelease>\let\@strip@tex@ext\@undefined
%<latexrelease>\let\@strip@tex@ext@aux\@undefined
%<latexrelease>
%<latexrelease>\EndIncludeInRelease
% \end{macrocode}
%
% \begin{macrocode}
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\includeonly}{Spaces in file names}%
%<latexrelease>\def\includeonly#1{%
%<latexrelease> \@partswtrue
%<latexrelease> \edef\@partlist{\zap@space#1 \@empty}}
%<latexrelease>
%<latexrelease>\def\include#1{\relax
%<latexrelease> \ifnum\@auxout=\@partaux
%<latexrelease> \@latex@error{\string\include\space cannot be nested}\@eha
%<latexrelease> \else \@include#1 \fi}
%<latexrelease>
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
%
% \begin{macro}{\@include}
% \changes{v1.2g}{2020/05/02}{Support spaces in filenames by enclosing
% the names of \texttt{.aux}-files in quotes (gh/217)}
% \begin{macrocode}
%</2ekernel>
%<*2ekernel|latexrelease>
%<latexrelease>\IncludeInRelease{2022/06/01}%
%<latexrelease> {\@include}{Spaces in file names and hooks}%
% \end{macrocode}
%
% \changes{v1.2j}{2020/10/04}{Quotes around the aux file name removed,
% they are not needed and upset BibTeX (gh/400)}
% \changes{v1.2p}{2021/10/14}{Warn about use in preamble}
% \begin{macrocode}
\def\@include#1 {%
% \end{macrocode}
%
% \begin{macrocode}
\ifx\@nodocument\relax
% \end{macrocode}
%
% \begin{macrocode}
\clearpage
\if@filesw
\immediate\write\@mainaux{\string\@input{#1.aux}}%
\fi
\@tempswatrue
\if@partsw
\@tempswafalse
\edef\reserved@b{#1}%
\@for\reserved@a:=\@partlist\do
{\ifx\reserved@a\reserved@b\@tempswatrue\fi}%
\fi
\if@tempswa
\let\@auxout\@partaux
\if@filesw
\immediate\openout\@partaux "#1.aux"
\immediate\write\@partaux{\relax}%
\fi
% \end{macrocode}
% Now before going to the hooks we need to set \cs{CurrentFile}:
% \begin{macrocode}
%-----------------------------------------
\@filehook@set@CurrentFile
% \end{macrocode}
% Execute the \texttt{before} hooks just after we switched the
% \texttt{.aux} file \ldots
% \changes{v1.2n}{2021/07/23}{Make include/name/before a one-time hook}
% \changes{v1.2o}{2021/08/25}{Standardise generic hook names (gh/648)}
% \begin{macrocode}
\UseHook{include/before}%
\UseOneTimeHook{include/#1/before}%
%-----------------------------------------
\@input@{#1.tex}%
%-----------------------------------------
% \end{macrocode}
% \ldots{} then \texttt{end} hooks \ldots
% \changes{v1.2n}{2021/07/23}{Make include/name/end a one-time hook}
% \begin{macrocode}
\UseOneTimeHook{include/#1/end}%
\UseHook{include/end}%
%-----------------------------------------
\clearpage
%-----------------------------------------
% \end{macrocode}
% \ldots{} and after the \cs{clearpage} the \texttt{after} hooks
% followed by another \cs{clearpage} just in case new material got
% added (after all we need to be in well defined state after the
% \cs{include}).
% \changes{v1.2n}{2021/07/23}{Make include/name/after a one-time hook}
% \begin{macrocode}
\UseOneTimeHook{include/#1/after}%
\UseHook{include/after}%
\clearpage
%-----------------------------------------
\@writeckpt{#1}%
\if@filesw
\immediate\closeout\@partaux
\fi
\else
% \end{macrocode}
% If the file is not included, reset |\deadcycles|, so that a long
% list of non-included files does not generate an `Output loop'
% error.
% \changes{v1.1j}{1997/01/08}{reset \cs{deadcycles} latex/2365}
% \begin{macrocode}
\deadcycles\z@
\@nameuse{cp@#1}%
% \end{macrocode}
% We also execute a hook in this case, first a general used for
% every include file that is exclude and then a specific one that
% contains the name of the include file.
% \changes{v1.2q}{2022/04/01}{Process some hooks is an include file is bypassed}
% \begin{macrocode}
%-----------------------------------------
\UseHook{include/excluded}%
\UseOneTimeHook{include/#1/excluded}%
%-----------------------------------------
\fi
\let\@auxout\@mainaux
% \end{macrocode}
%
% \begin{macrocode}
\else
\@latex@warning{%
\noexpand\include should only be used after \string\begin{document}}%
\@input@{#1}%
\fi}
% \end{macrocode}
%
% \changes{v1.2o}{2021/08/25}{Declare non-generic include hooks}
% Now declare the non-generic \hook{include} hooks used above:
% \begin{macrocode}
\NewHook{include/before}
\NewReversedHook{include/end}
\NewReversedHook{include/after}
\NewHook{include/excluded}
%<latexrelease>\EndIncludeInRelease
%</2ekernel|latexrelease>
% \end{macrocode}
%
% \begin{macrocode}
%<latexrelease>\IncludeInRelease{2020/10/01}%
%<latexrelease> {\@include}{Spaces in file names and hooks}%
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\def\@include#1 {%
%<latexrelease>\ifx\@nodocument\relax
%<latexrelease> \clearpage
%<latexrelease> \if@filesw
%<latexrelease> \immediate\write\@mainaux{\string\@input{#1.aux}}%
%<latexrelease> \fi
%<latexrelease> \@tempswatrue
%<latexrelease> \if@partsw
%<latexrelease> \@tempswafalse
%<latexrelease> \edef\reserved@b{#1}%
%<latexrelease> \@for\reserved@a:=\@partlist\do
%<latexrelease> {\ifx\reserved@a\reserved@b\@tempswatrue\fi}%
%<latexrelease> \fi
%<latexrelease> \if@tempswa
%<latexrelease> \let\@auxout\@partaux
%<latexrelease> \if@filesw
%<latexrelease> \immediate\openout\@partaux "#1.aux"
%<latexrelease> \immediate\write\@partaux{\relax}%
%<latexrelease> \fi
%<latexrelease> \@filehook@set@CurrentFile
%<latexrelease> \UseHook{include/before}%
%<latexrelease> \UseOneTimeHook{include/#1/before}%
%<latexrelease> \@input@{#1.tex}%
%<latexrelease> \UseOneTimeHook{include/#1/end}%
%<latexrelease> \UseHook{include/end}%
%<latexrelease> \clearpage
%<latexrelease> \UseOneTimeHook{include/#1/after}%
%<latexrelease> \UseHook{include/after}%
%<latexrelease> \clearpage
%<latexrelease> \@writeckpt{#1}%
%<latexrelease> \if@filesw
%<latexrelease> \immediate\closeout\@partaux
%<latexrelease> \fi
%<latexrelease> \else
%<latexrelease> \deadcycles\z@
%<latexrelease> \@nameuse{cp@#1}%
%<latexrelease> \fi
%<latexrelease> \let\@auxout\@mainaux
%<latexrelease>\else
%<latexrelease>\@latex@warning{%
%<latexrelease> \noexpand\include should only be used after \string\begin{document}}%
%<latexrelease>\@input@{#1}%
%<latexrelease>\fi}
%<latexrelease>\NewHook{include/before}
%<latexrelease>\NewReversedHook{include/end}
%<latexrelease>\NewReversedHook{include/after}
% \end{macrocode}
%
% \begin{macrocode}
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\@include}{Spaces in file names and hooks}%
%<latexrelease>\def\@include#1 {%
%<latexrelease> \clearpage
%<latexrelease> \if@filesw
%<latexrelease> \immediate\write\@mainaux{\string\@input{#1.aux}}%
%<latexrelease> \fi
%<latexrelease> \@tempswatrue
%<latexrelease> \if@partsw
%<latexrelease> \@tempswafalse
%<latexrelease> \edef\reserved@b{#1}%
%<latexrelease> \@for\reserved@a:=\@partlist\do
%<latexrelease> {\ifx\reserved@a\reserved@b\@tempswatrue\fi}%
%<latexrelease> \fi
%<latexrelease> \if@tempswa
%<latexrelease> \let\@auxout\@partaux
%<latexrelease> \if@filesw
%<latexrelease> \immediate\openout\@partaux #1.aux
%<latexrelease> \immediate\write\@partaux{\relax}%
%<latexrelease> \fi
%<latexrelease> \@input@{#1.tex}%
%<latexrelease> \clearpage
%<latexrelease> \@writeckpt{#1}%
%<latexrelease> \if@filesw
%<latexrelease> \immediate\closeout\@partaux
%<latexrelease> \fi
%<latexrelease> \else
%<latexrelease> \deadcycles\z@
%<latexrelease> \@nameuse{cp@#1}%
%<latexrelease> \fi
%<latexrelease> \let\@auxout\@mainaux}
%<latexrelease>
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@writeckpt}
% \begin{macrocode}
\def\@writeckpt#1{%
\if@filesw
\immediate\write\@partaux{\string\@setckpt{#1}\@charlb}%
{\let\@elt\@wckptelt \cl@@ckpt}%
\immediate\write\@partaux{\@charrb}%
\fi}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@wckptelt}
% \begin{macrocode}
\def\@wckptelt#1{%
\immediate\write\@partaux{%
\string\setcounter{#1}{\the\@nameuse{c@#1}}}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@setckpt}
% RmS 93/08/31: introduced |\@setckpt|
% \begin{macrocode}
\def\@setckpt#1{\global\@namedef{cp@#1}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@charlb}
% \begin{macro}{\@charrb}
% The following defines |\@charlb| and |\@charrb| to be |{| and |}|,
% respectively with |\catcode| 11.
% \begin{macrocode}
{\catcode`[=1 \catcode`]=2
\catcode`{=11 \catcode`}=11
\gdef\@charlb[{]
\gdef\@charrb[}]
]% }brace matching
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \subsection{Safe Input Macros}
%
%
%
% \begin{macro}{\@curr@file}
% \begin{macro}{\set@curr@file}
%
% File name handling is done by generating a csname from the
% provided file name (which means that UTF-8 octets gets turned into
% strings as this is what happens if they appear in a csname due to
% the code in \texttt{utf8.def}). By setting \cs{escapchar} to
% \texttt{-1} we ensure that we don't get a backslash in front. As a
% result we end up with all characters as catcode 12 (plus
% spaces). We then sometimes add quotes around the construct
% (removing any existing inner quotes. Sometimes we only remove the
% quotes if they have been supplied by the user. There is clearly
% some room for improvement.
%
% A side effect of the new code is that we will see quotes around
% file name displays where there haven't been any before.
%
% For compatibility with existing code using |{abc}.tex| or
% |{one.two}.png|, an initial brace group is discarded before
% expansion and |\string| is applied. The content of the brace
% group is discarded. This means that a leading space will be lost
% unless protected (by |{ }| or |" "| or |\space|) but filenames
% with a space are hopefully rare.
%
% \changes{v1.2a}{2019/07/01}{Support UTF-8}
% \changes{v1.2c}{2019/10/11}{Remove one brace group}
% \changes{v1.2d}{2019/10/26}{remove quotes}
% \changes{v1.2e}{2019/11/09}{expand and \cs{string} before removing quotes}
%
% The definition below is from 2019 and only used during kernel
% bootstrapping, later on in \texttt{ltfilehook.dtx} it will get
% overwritten.
% \begin{macrocode}
\def\set@curr@file#1{%
\begingroup
\escapechar\m@ne
\xdef\@curr@file{%
\expandafter\expandafter\expandafter\unquote@name
\expandafter\expandafter\expandafter{%
\expandafter\string
\csname\@firstofone#1\@empty\endcsname}}%
\endgroup
}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
% \begin{macro}{\quote@name}
% \begin{macro}{\quote@@name}
% \begin{macro}{\unquote@name}
% Quoting spaces
%\begin{verbatim}
% a b c -> "a b c"
% "a b c" -> "a b c"
% a" "b" "c -> "a b c"
% -> ""
%\end{verbatim}
% \begin{macrocode}
%</2ekernel>
%<*2ekernel|latexrelease>
%<latexrelease>\IncludeInRelease{2019/10/01}%
%<latexrelease> {\quote@name}{Quote file names}%
\def\quote@name#1{"\quote@@name#1\@gobble""}
\def\quote@@name#1"{#1\quote@@name}
% \end{macrocode}
% and removing quotes \ldots
% \begin{macrocode}
\def\unquote@name#1{\quote@@name#1\@gobble"}
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
%
%
% \begin{macro}{\IfFileExists}
%
% \changes{v1.2a}{2019/07/01}{Support UTF-8}
% \changes{v1.2b}{2019/08/27}{Make command robust}
% \changes{v1.2d}{2019/10/26}{don't quote name}
% \begin{macrocode}
\DeclareRobustCommand\IfFileExists[1]{%
\set@curr@file{#1}%
\expandafter\IfFileExists@\expandafter{\@curr@file}}
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\quote@name}{Quote file names}%
%<latexrelease>
%<latexrelease>\let\quote@name\@undefined
%<latexrelease>\let\quote@@name\@undefined
%<latexrelease>\let\unquote@name\@undefined
%<latexrelease>
%<latexrelease>\long\def \IfFileExists#1#2#3{%
%<latexrelease> \openin\@inputcheck#1 %
%<latexrelease> \ifeof\@inputcheck
%<latexrelease> \ifx\input@path\@undefined
%<latexrelease> \def\reserved@a{#3}%
%<latexrelease> \else
%<latexrelease> \def\reserved@a{\@iffileonpath{#1}{#2}{#3}}%
%<latexrelease> \fi
%<latexrelease> \else
%<latexrelease> \closein\@inputcheck
%<latexrelease> \edef\@filef@und{#1 }%
%<latexrelease> \def\reserved@a{#2}%
%<latexrelease> \fi
%<latexrelease> \reserved@a}
%<latexrelease>
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
%
%
%
% \begin{macro}{\IfFileExists@}
% \changes{v0.9b}{1993/12/04}{Macro added}
% \changes{v0.9p}{1994/01/18}{New Definition}
% \changes{v1.0t}{1995/05/25}{(CAR) added \cs{long}}
% \changes{v1.2d}{2019/10/26}{quote on openin}
% \changes{v1.2k}{2021/03/12}{Allow unbalanced conditionals (gh/530)}
% \changes{v1.2t}{2023/05/15}{Use \pkg{expl3} file existence test}
% \begin{macro}{\IfFileExists@@}
% \changes{v1.2t}{2023/05/15}{Macro added}
% \changes{v1.2u}{2023/06/16}{Support piped input}
% Argument |#1| is |\@curr@file| so catcode 12 string with no quotes.
%
% The original definition picked up arguments |#2| and |#3| in a
% way that they couldn't contain unbalanced conditionals. A better
% implementation would have been not to pick up the arguments at
% all but instead use the usual \cs{@firstoftwo} and
% \cs{secondoftwo}. However, that changes how |#| is interpreted
% and so we can't do that nowadays without invalidating a lot of
% code. Therefore the somewhat curious construction near the end.
%
% Earlier versions used |\openin| here, but this led to two
% code paths, one in \pkg{expl3} and one here. To avoid that,
% and as the \pkg{expl3} approach works by expansion, we use
% that here. As we need the file name to include the path,
% the actual \pkg{expl3} function used is not the file existence
% test!
% \begin{macrocode}
%</2ekernel>
%<*2ekernel|latexrelease>
%<latexrelease>\IncludeInRelease{2023/06/01}%
%<latexrelease> {\IfFileExists@}{IfFileExists}
\long\def \IfFileExists@#1#2#3{%
\edef\@filef@und{\IfFileExists@@{#1}}%
% \end{macrocode}
% The \pkg{expl3} function regards an empty argument as nothing at all,
% but the \LaTeXe{} convention is that this is equal to the special
% \texttt{.tex} file.
% \begin{macrocode}
\ifx\@filef@und\@empty
\if\relax\detokenize{#1}\relax
\let\reserved@a\@firstoftwo
\def\@filef@und{".tex" }%
\else
\let\reserved@a\@secondoftwo
\fi
\else
\let\reserved@a\@firstoftwo
\edef\@filef@und{"\@filef@und" }%
\fi
% \end{macrocode}
% This is just there so that any |#| inside |#2| or |#3| needs
% doubling (as that was the case in the past).
% \begin{macrocode}
\expandafter\def\expandafter\reserved@a
\expandafter{\reserved@a{#2}{#3}}%
\reserved@a}
% \end{macrocode}
% Pipes are not really files, but at the document level they are supported.
% To quickly trim of any leading spaces, we use a blank test and \cs{use:n}
% rather than \cs{tl_trim_spaces:n} for speed as we don't care about the end
% of the input.
% \begin{macrocode}
\ExplSyntaxOn
\cs_new:Npn \IfFileExists@@ #1
{
\tl_if_blank:nF {#1}
{
\tl_if_head_eq_charcode:oNTF { \use:n #1 } |
{#1}
{ \file_full_name:n {#1} }
}
}
\cs_generate_variant:Nn \tl_if_head_eq_charcode:nNTF { o }
\ExplSyntaxOff
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{2021/06/01}%
%<latexrelease> {\IfFileExists@}{IfFileExists}
%<latexrelease>
%<latexrelease>\long\def \IfFileExists@#1#2#3{%
%<latexrelease> \openin\@inputcheck"#1" %
%<latexrelease> \ifeof\@inputcheck
%<latexrelease> \ifx\input@path\@undefined
%<latexrelease> \let\reserved@a\@secondoftwo
%<latexrelease> \else
%<latexrelease> \def\reserved@a{\@iffileonpath{#1}}%
%<latexrelease> \fi
%<latexrelease> \else
%<latexrelease> \closein\@inputcheck
%<latexrelease> \edef\@filef@und{"#1" }%
%<latexrelease> \let\reserved@a\@firstoftwo
%<latexrelease> \fi
%<latexrelease> \expandafter\def\expandafter\reserved@a
%<latexrelease> \expandafter{\reserved@a{#2}{#3}}%
%<latexrelease>\reserved@a}
%<latexrelease>\let\IfFileExists@@\@undefined
%<latexrelease>\EndIncludeInRelease
%<latexrelease>
%<latexrelease>\IncludeInRelease{2019/10/01}%
%<latexrelease> {\IfFileExists@}{IfFileExists}
%<latexrelease>
%<latexrelease>\long\def \IfFileExists@#1#2#3{%
%<latexrelease> \openin\@inputcheck"#1" %
%<latexrelease> \ifeof\@inputcheck
%<latexrelease> \ifx\input@path\@undefined
%<latexrelease> \def\reserved@a{#3}%
%<latexrelease> \else
%<latexrelease> \def\reserved@a{\@iffileonpath{#1}{#2}{#3}}%
%<latexrelease> \fi
%<latexrelease> \else
%<latexrelease> \closein\@inputcheck
%<latexrelease> \edef\@filef@und{"#1" }%
%<latexrelease> \def\reserved@a{#2}%
%<latexrelease> \fi
%<latexrelease> \reserved@a}
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\IfFileExists@}{IfFileExists}
%<latexrelease>
%<latexrelease>\let\IfFileExists@\@undefined
%<latexrelease>
%<latexrelease>
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
% \end{macro}
% \end{macro}
%
%
%
%
%
%
% \begin{macro}{\@iffileonpath}
% If the file is not found by |\openin|, and |\input@path| is defined,
% look in all the directories specified in |\input@path|.
% \changes{v0.9p}{1994/01/18}{Macro added}
% \changes{v1.0f}{1994/05/02}
% {\cs{@break@loop} renamed to \cs{@break@tfor}}
% \changes{v1.0t}{1995/05/25}
% {(CAR) added \cs{long}}
% \changes{v1.1d}{1996/01/10}
% {Change argument handling to not require doubled hash. latex/2024}
% \changes{v1.2d}{2019/10/26}{quote on openin}%
% \changes{v1.2f}{2019/11/11}{make \cs{@filef@und} match quoting used on \cs{openin}}%
% \begin{macrocode}
%</2ekernel>
%<*2ekernel|latexrelease>
%<latexrelease>\IncludeInRelease{2019/10/01}%
%<latexrelease> {\@iffileonpath}{Quote file names}
\long\def\@iffileonpath#1{%
\let\reserved@a\@secondoftwo
\expandafter\@tfor\expandafter\reserved@b\expandafter
:\expandafter=\input@path\do{%
\openin\@inputcheck\expandafter\quote@name\expandafter{\reserved@b#1} %
\ifeof\@inputcheck\else
\edef\@filef@und{\expandafter\quote@name\expandafter{\reserved@b#1} }%
\let\reserved@a\@firstoftwo%
\closein\@inputcheck
\@break@tfor
\fi}%
\reserved@a}
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\quote@name}{Quote file names}
%<latexrelease>
%<latexrelease>\long\def\@iffileonpath#1{%
%<latexrelease> \let\reserved@a\@secondoftwo
%<latexrelease> \expandafter\@tfor\expandafter\reserved@b\expandafter
%<latexrelease> :\expandafter=\input@path\do{%
%<latexrelease> \openin\@inputcheck\reserved@b#1 %
%<latexrelease> \ifeof\@inputcheck\else
%<latexrelease> \edef\@filef@und{\reserved@b#1 }%
%<latexrelease> \let\reserved@a\@firstoftwo%
%<latexrelease> \closein\@inputcheck
%<latexrelease> \@break@tfor
%<latexrelease> \fi}%
%<latexrelease> \reserved@a}
%<latexrelease>
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
%
%
%
%
% \begin{macro}{\InputIfFileExists}
%
% Now define |\InputIfFileExists| to input |#1| if it seems to exist.
% Immediately prior to the input, |#2| is executed.
% If the file |#1| does not exist, execute `|#3|'.
%
% This here is a temporary definition for the kernel. The real one
% comes somewhat later in the file \texttt{ltfilehook.dtx}.
%
% \begin{macrocode}
\DeclareRobustCommand \InputIfFileExists[2]{%
\IfFileExists{#1}%
{%
\expandafter\@swaptwoargs\expandafter
{\@filef@und}{#2\@addtofilelist{#1}\@@input}}}
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\@swaptwoargs}
%
% \changes{v1.1o}{2019/02/07}{Helper macro added}
% Swap two arguments and return them unbraced (like
% \cs{@firstoftwo} etc).
% \begin{macrocode}
%</2ekernel>
%<*2ekernel|latexrelease>
%<latexrelease>\IncludeInRelease{2019/10/01}%
%<latexrelease> {\@swaptwoargs}{Don't lose the file name}%
\long\def\@swaptwoargs#1#2{#2#1}
% \end{macrocode}
%
% \begin{macrocode}
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\@swaptwoargs}{Don't lose the file name}%
%<latexrelease>\let\@swaptwoargs\@undefined
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
% \end{macro}
%
%
% \begin{macro}{\input}
% Input a file: if the argument is given in braces use safe input
% macros, otherwise use \TeX's primitive |\input| command (which is
% called |\@@input| in \LaTeX).
% \changes{v0.9b}{1993/12/04}{Macro reimplemented}
% \begin{macrocode}
\def\input{\@ifnextchar\bgroup\@iinput\@@input}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@iinput}
% Define |\@iinput| (i.e., |\input|) in terms of
% |\InputIfIfileExists|.
% \changes{v0.9b}{1993/12/04}{Macro reimplemented}
%
% Changes to \cs{@iinput}: adapt to the changes to
% \cs{@missingfileerror}.
% \begin{macrocode}
%</2ekernel>
%<*2ekernel|latexrelease>
%<latexrelease>\IncludeInRelease{2020/10/01}%
%<latexrelease> {\@iinput}{Change in file error handling}%
\def\@iinput#1{%
\InputIfFileExists{#1}{}%
{\filename@parse\@curr@file
\edef\reserved@a{\noexpand\@missingfileerror
{\filename@area\filename@base}%
{\ifx\filename@ext\relax tex\else\filename@ext\fi}}%
% \end{macrocode}
% This line now just sets \cs[no-index]{@missingfile@\meta{part}}:
% \begin{macrocode}
\reserved@a
% \end{macrocode}
% Now here we have to use it. The file here is guaranteed to exist,
% because \cs{@missingfileerror} ensures so, but we have to use
% \cs{InputIfFileExists} because it executes the file hooks.
% \begin{macrocode}
\edef\reserved@a{\noexpand\@iinput{%
\@missingfile@area\@missingfile@base.\@missingfile@ext}}%
\reserved@a}}
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
% \end{macrocode}
%
% \begin{macrocode}
%<latexrelease>\IncludeInRelease{2019/10/01}%
%<latexrelease> {\@iinput}{Quote file names}%
%<latexrelease>
%<latexrelease>\def\@iinput#1{%
%<latexrelease> \InputIfFileExists{#1}{}%
%<latexrelease> {\filename@parse\@curr@file
%<latexrelease> \edef\reserved@a{\noexpand\@missingfileerror
%<latexrelease> {\filename@area\filename@base}%
%<latexrelease> {\ifx\filename@ext\relax tex\else\filename@ext\fi}}%
%<latexrelease> \reserved@a}}
%<latexrelease>\EndIncludeInRelease
% \end{macrocode}
%
% \begin{macrocode}
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\@iinput}{Quote file names}%
%<latexrelease>\def\@iinput#1{%
%<latexrelease> \InputIfFileExists{#1}{}%
%<latexrelease> {\filename@parse{#1}%
%<latexrelease> \edef\reserved@a{\noexpand\@missingfileerror
%<latexrelease> {\filename@area\filename@base}%
%<latexrelease> {\ifx\filename@ext\relax tex\else\filename@ext\fi}}%
%<latexrelease> \reserved@a}}
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@input}
% \changes{v0.9b}{1993/12/04}{Macro reimplemented}
% \changes{v0.9p}{1994/01/18}%
% {do not use a different definition for \cs{input@path}}
% Define |\@input| in terms of |\IfIfileExists|.
% So this is a `safe input' command, but the files input are not
% listed by |\listfiles|.
%
% We don't want |.aux|, |.toc| files etc be listed by |\listfiles|.
% However, something like |.bbl| probably should be listed and thus
% should be implemented not by |\@input|.
% \begin{macrocode}
\def\@input#1{%
\IfFileExists{#1}{\@@input\@filef@und}{\typeout{No file #1.}}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@input@}
% \changes{v0.9p}{1994/01/18}{Macro added}
% \task{???}{share code with `@input ?}
% Version of |\@input| that does add the file to |\@filelist|.
% \begin{macrocode}
\def\@input@#1{\InputIfFileExists{#1}{}{\typeout{No file #1.}}}
% \end{macrocode}
% \end{macro}
%
%
%
%
%
%
% \begin{macro}{\@missingfileerror}
% This `error' command avoids \TeX's primitive missing file loop.
%
% Missing file error. Prompt for a new filename, offering a default
% extension.
% \changes{LaTeX2e}{1993/11/21}
% {Stop infinite looping on \cs{@er@ext}}
% \changes{LaTeX2e}{1993/11/28}
% {Use filename parser from dircheck}
% \changes{LaTeX2e}{1994/03/15}
% {Quit on x or X just like a real error}
% \changes{LaTeX2e}{1994/05/26}
% {Modify message format}
% \changes{v1.0j}{1994/11/03}
% {Move here from ltclass}
% \changes{v1.0w}{1995/10/06}
% {Autoload error}
%
% Changes to \cs{@missingfileerror}: rather than trying to input the
% file by force, now \cs{@missingfileerror} just returns three
% \cs[no-index]{@missingfile@\meta{part}} and the caller macro is
% responsible for doing the right thing with it.
% \begin{macrocode}
%</2ekernel>
%<*2ekernel|latexrelease>
%<latexrelease>\IncludeInRelease{2020/10/01}%
%<latexrelease> {\@missingfileerror}{Do not load missing file immediately}%
\gdef\@missingfileerror#1#2{%
\typeout{^^J! LaTeX Error: File `#1.#2' not found.^^J^^J%
Type X to quit or <RETURN> to proceed,^^J%
or enter new name. (Default extension: #2)^^J}%
\message{Enter file name: }%
{\endlinechar\m@ne
\global\read\m@ne to\@gtempa}%
\ifx\@gtempa\@empty
% \end{macrocode}
% If the user answers with \meta{return}, fallback to the |.tex| file
% (previously it did nothing).
% \begin{macrocode}
\let\@missingfile@area\@empty
\let\@missingfile@base\@empty
\def\@missingfile@ext{tex}%
\else
% \end{macrocode}
% Use \cs{batchmode}\cs{read}|-1 to |\meta{tl} to end the \TeX{} run,
% same as \pkg{expl3} does (it was \cs{batchmode}\cs{@@end} before).
% \begin{macrocode}
\def\reserved@b{\batchmode\read-1 to \reserved@a}%
\def\reserved@a{x}\ifx\reserved@a\@gtempa\reserved@b\fi
\def\reserved@a{X}\ifx\reserved@a\@gtempa\reserved@b\fi
\filename@parse\@gtempa
\edef\filename@ext{%
\ifx\filename@ext\relax#2\else\filename@ext\fi}%
\edef\reserved@a{%
% \end{macrocode}
% Only check \cs{IfFileExists} (it was \cs{InputIfFileExists}).
% \begin{macrocode}
\noexpand\IfFileExists
{\filename@area\filename@base.\filename@ext}%
% \end{macrocode}
% If the file exists, define \cs[no-index]{@missingfile@\meta{part}}.
% \begin{macrocode}
{\def\noexpand\@missingfile@area{\filename@area}%
\def\noexpand\@missingfile@base{\filename@base}%
\def\noexpand\@missingfile@ext {\filename@ext}}%
{\noexpand\@missingfileerror
{\filename@area\filename@base}{\filename@ext}}}%
\reserved@a
\fi
}
%</2ekernel|latexrelease>
%<latexrelease>\EndIncludeInRelease
% \end{macrocode}
%
% \begin{macrocode}
%<latexrelease>\IncludeInRelease{0000/00/00}%
%<latexrelease> {\@missingfileerror}{Do not load missing file immediately}%
%<latexrelease>
%<latexrelease>\gdef\@missingfileerror#1#2{%
%<latexrelease> \typeout{^^J! LaTeX Error: File `#1.#2' not found.^^J^^J%
%<latexrelease> Type X to quit or <RETURN> to proceed,^^J%
%<latexrelease> or enter new name. (Default extension: #2)^^J}%
%<latexrelease> \message{Enter file name: }%
%<latexrelease> {\endlinechar\m@ne
%<latexrelease> \global\read\m@ne to\@gtempa}%
%<latexrelease> \ifx\@gtempa\@empty
%<latexrelease> \else
%<latexrelease> \def\reserved@a{x}\ifx\reserved@a\@gtempa\batchmode\@@end\fi
%<latexrelease> \def\reserved@a{X}\ifx\reserved@a\@gtempa\batchmode\@@end\fi
%<latexrelease> \filename@parse\@gtempa
%<latexrelease> \edef\filename@ext{%
%<latexrelease> \ifx\filename@ext\relax#2\else\filename@ext\fi}%
%<latexrelease> \edef\reserved@a{%
%<latexrelease> \noexpand\InputIfFileExists
%<latexrelease> {\filename@area\filename@base.\filename@ext}%
%<latexrelease> {}%
%<latexrelease> {\noexpand\@missingfileerror
%<latexrelease> {\filename@area\filename@base}{\filename@ext}}}%
%<latexrelease> \reserved@a
%<latexrelease> \fi}
%<latexrelease>
%<latexrelease>\EndIncludeInRelease
%<*2ekernel>
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@obsoletefile}
% For compatibility with \LaTeX~2.09 document styles, we distribute
% files called |article.sty|, |book.sty|, |report.sty|,
% |slides.sty| and |letter.sty|. These use the command
% |\@obsoletefile|, which produces a warning message.
% \changes{v0.9m}{1993/12/20}{Added this command, removed
% @oldfilewarning}
% \changes{v1.0f}{1994/05/02}{Make \cs{@onlypreamble}}
% \begin{macrocode}
\def\@obsoletefile#1#2{%
\@latex@warning@no@line{inputting `#1' instead of obsolete `#2'}}
\@onlypreamble\@obsoletefile
% \end{macrocode}
%
% \subsection{Listing files}
%
% \begin{macro}{\@filelist}
% A list of files input so far. The initial value of |\@gobble| eats
% the comma before the first file name.
% \begin{macrocode}
\let\@filelist\@gobble
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@addtofilelist}
% Add to the list of files input so far.
% \changes{LaTeX2e}{1994/03/13}
% {Macro added}
% \changes{LaTeX2e}{1995/10/01}
% {Macro added}
% This `real' definition is only used for `cfg' files during initex.
% An initial definition of |\@gobble| has already been set.
% \begin{macrocode}
%\def\@addtofilelist#1{\xdef\@filelist{\@filelist,#1}}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\listfiles}
% A preamble command to cause |\end{document}| to list files input
% from the main file.
% \changes{LaTeX2e}{1993/11/22}
% {Removed checking for \cs{@unknownversion}}
% \changes{LaTeX2e}{1994/01/17}
% {New Version, adds `.tex' if needed, and lines up columns}
% \changes{LaTeX2e}{1994/05/13}
% {Stop \cs{listfiles} being run twice}
% \changes{v1.0i}{1994/10/18}
% {code moved here from ltclass}
% \begin{macrocode}
\def\listfiles{%
\let\listfiles\relax
\def\@listfiles##1##2##3##4##5##6##7##8##9\@@{%
\def\reserved@d{\\}%
\@tfor\reserved@c:=##1##2##3##4##5##6##7##8\do{%
\ifx\reserved@c\reserved@d
\edef\filename@area{ \filename@area}%
\fi}}%
% \end{macrocode}
%
% \changes{v1.0o}{1994/11/30}
% {Use \cs{@dofilelist}}
% \changes{v1.2r}{2022/05/27}{Try saved version string, if ver@.. is \cs{relax} (gh/825)}
% \begin{macrocode}
\def\@dofilelist{%
\typeout{^^J *File List*}%
\@for\@currname:=\@filelist\do{%
\filename@parse\@currname
\edef\reserved@a{%
\filename@base.%
\ifx\filename@ext\relax tex\else\filename@ext\fi}%
\expandafter\let\expandafter\reserved@b
\csname ver@\reserved@a\endcsname
% \end{macrocode}
% Packages that \cs{relax} their \cs{ver@...} string to allow for
% multiple loading (e.g., \pkg{fontenc}) can use \cs{ver@@...} to
% store the version information instead.
% \begin{macrocode}
\ifx\reserved@b\relax
\expandafter\let\expandafter\reserved@b
\csname ver@@\reserved@a\endcsname
\fi
\expandafter\expandafter\expandafter\@listfiles\expandafter
\filename@area\filename@base\\\\\\\\\\\\\\\\\\\@@
\typeout{%
\filename@area\reserved@a
\ifx\reserved@b\relax\else\@spaces\reserved@b\fi}}%
\typeout{ ***********^^J}}}
% \end{macrocode}
%
% \changes{LaTeX2e}{1994/03/13}
% {Reset \cs{@addtofilelist} at begin document}
% \changes{LaTeX2e}{1994/03/16}
% {Move this code directly into \cs{document}}
% The |\@filelist| will be de-activated if |\listfiles| does not
% appear in the preamble. |\begin{document}| contains code equivalent
% to the following:
%\begin{verbatim}
% \AtBeginDocument{%
% \ifx\@listfiles\@undefined
% \let\@filelist\relax
% \let\@addtofilelist\@gobble
% \fi}
%\end{verbatim}
% \begin{macrocode}
\@onlypreamble\listfiles
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@dofilelist}
% \changes{v1.0o}{1994/11/30}
% {Macro added}
% \begin{macrocode}
\let\@dofilelist\relax
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
%</2ekernel>
% \end{macrocode}
% \end{macro}
%
% \Finale
%
