# Be sure that if tex wants to fail, it is not interactive:
       # close stdin.
       $TEX txiversion.tex </dev/null >txiversion.out 2>txiversion.err
    ); then :; else
      report "texinfo.tex appears to be broken.
This may be due to the environment variable TEX set to something
other than (plain) tex, a corrupt texinfo.tex file, or 
to tex itself simply not working."
      cat "$version_test_dir/txiversion.out"
      cat "$version_test_dir/txiversion.err" >&2
      error 1 "quitting."
    fi
    eval `$SED -n 's/^.*\[\(.*\)version \(....\)-\(..\)-\(..\).*$/txiformat=\1 txiversion="\2\3\4"/p' "$version_test_dir/txiversion.out"`
    verbose "texinfo.tex preloaded as \`$txiformat', version is \`$txiversion' ..."
    if test "$txiprereq" -le "$txiversion" >&6 2>&1; then
      makeinfo=
    else
      makeinfo=${MAKEINFO:-makeinfo}
    fi
    # If TeX is preloaded, offer the user this convenience:
    if test "$txiformat" = Texinfo; then
      escape=@
    fi
  fi

  if test -n "$makeinfo"; then
    # in_src: the file with macros expanded.
    # Use the same basename to generate the same aux file names.
    work_src=$workdir/src
    ensure_dir "$work_src"
    in_src=$work_src/$in_base
    run_mi_includes=`list_prefix includes -I`
    verbose "Macro-expanding $command_line_filename to $in_src ..."
    # eval $makeinfo because it might be defined as something complex
    # (running missing) and then we end up with things like '"-I"',
    # and "-I" (including the quotes) is not an option name.  This
    # happens with gettext 0.14.5, at least.
    eval $makeinfo -c TEXINFO_OUTPUT_FORMAT=plaintexinfo --iftex --no-ifinfo \
          --footnote-style=end -I "$in_dir" $run_mi_includes \
            "$command_line_filename" >"$in_src"
    # Continue only if everything succeeded.
    if test $? -ne 0 \
       || test ! -r "$in_src"; then
      verbose "Expansion failed, ignored...";
    else
      in_input=$in_src
    fi
  fi
}


# insert_commands - Insert $textra commands at the beginning of the file. 
# Recommended to be used for @finalout, @smallbook, etc.
insert_commands ()
{
  if test -n "$textra"; then
    # _xtr.  The file with the user's extra commands.
    work_xtr=$workdir/xtr
    in_xtr=$work_xtr/$in_base
    ensure_dir "$work_xtr"
    verbose "Inserting extra commands: $textra"
    case $in_lang in
      latex)   textra_cmd=1i;;
      texinfo)
        textra_cmd='/^\\input texinfo/a'
        # insert after @setfilename line if present
        if head -n 10 $in_input | grep '^@setfilename' ; then
          textra_cmd='/^@setfilename/a'
        fi
        ;;
      *)       error 1 "internal error, unknown language: $in_lang";;
    esac
    $SED "$textra_cmd\\
$textra" "$in_input" >"$in_xtr"
    in_input=$in_xtr
  fi
}


# compute_language FILENAME - Return the short string for the language
# in which FILENAME is written: `texinfo' or `latex'.
compute_language ()
{
  # If the user explicitly specified the language, use that.
  # Otherwise, if the first line is \input texinfo, assume it's texinfo.
  # Otherwise, guess from the file extension.
  if test -n "$set_language"; then
    echo $set_language
  elif $SED 1q "$1" | grep 'input texinfo' >&6; then
    echo texinfo
  else
    # Get the type of the file (latex or texinfo) from the given language
    # we just guessed, or from the file extension if not set yet.
    case $1 in
      *.ltx | *.tex | *.drv | *.dtx) echo latex;;
      *)                             echo texinfo;;
    esac
  fi
}


# compile - Run the full compilation chain, from pre-processing to
# installation of the output at its expected location.
compile ()
{
  # Set include path for tools:
  #   .  Include current directory in case there are files there already, so
  #     we don't have more TeX runs than necessary.  orig_pwd is used in case 
  #     we are in clean build mode, where we have cd'd to a temp directory.
  #   .  Include directory containing file, in case there are other
  #     files @include'd.
  #   .  Keep a final path_sep to get the default (system) TeX
  #     directories included.
  #   .  If we have any includes, put those at the end.

  common="$orig_pwd$path_sep$in_dir$path_sep"
  #
  txincludes=`list_infix includes $path_sep`
  test -n "$txincludes" && common="$common$txincludes$path_sep"
  #
  for var in $tex_envvars; do
    eval val="\$common\$${var}_orig"
    # Convert relative paths to absolute paths, so we can run in another
    # directory (e.g., in clean build mode, or during the macro-support
    # detection).
    val=`absolute_filenames "$val"`
    eval $var="\"$val\""
    export $var
    eval verbose \"$var=\'\$${var}\'\"
  done

  # --expand
  run_makeinfo

  # --command, --texinfo
  insert_commands

  # Run until a fixed point is reached.
  run_tex_suite
}

# make_openout_test FLAGS EXTENSION
# - Run TeX with an input file that performs an \openout.  Pass FLAGS to TeX.
#
make_openout_test ()
{
    recorder_option_maybe="$1"
    make_tex_cmd

    ensure_dir "$workdir"/check_recorder
    cd_dir "$workdir"/check_recorder

    cat > openout.tex <<EOF
\newwrite\ourwrite
\immediate\openout\ourwrite dum.dum
\bye
EOF
    # \bye doesn't work for LaTeX, but it will cause latex
    # to exit with an input error.
    tex_cmd="$tex_cmd '${escape}input' ./openout.tex"
    # ./ in case . isn't in path
    verbose "$0: running $tex_cmd ..."
    rm -fr "openout.$2"
    (eval "$tex_cmd" >/dev/null 2>&1)
}

# Check tex supports -recorder option
check_recorder_support ()
{
  verbose "Checking TeX recorder support..."
  make_openout_test " -recorder" fls
  if test -f openout.fls && grep '^OUTPUT dum.dum$' openout.fls > /dev/null
  then
    cd_orig
    verbose "Checking TeX recorder support... yes"
    return 0
  else
    cd_orig
    verbose "Checking TeX recorder support... no"
    return 1
  fi
}

# Check tex supports \openout traces in log
check_openout_in_log_support ()
{
  verbose "Checking TeX \openout in log support..."
  make_openout_test "" log
  if test -f openout.log \
     && grep '^\\openout..\? *= *`\?dum\.dum'\''\?' openout.log >/dev/null
  then
    cd_orig
    verbose "Checking TeX \openout in log support... yes"
    return 0
  else
    cd_orig
    verbose "Checking TeX \openout in log support... no"
    return 1
  fi
}

# Set that output auxiliary files are detected with the -recorder option,
# which creates a file JOBNAME.fls which is a machine-readable listing of
# files read and written during the job.
set_aux_files_from_fls ()
{
  recorder_option_maybe=" -recorder"
  generated_files_get_method=generated_files_get_from_fls
}

# Set that output auxiliary files are detected with searching for \openout
# in the log file.
set_aux_files_from_log ()
{
  recorder_option_maybe=''
  generated_files_get_method=generated_files_get_from_log
}

aux_files_error='Your TeX installation appears to be broken - texi2dvi
cannot determine auxiliary files output from a TeX run.

You may need to install TeX, or change the values of your PATH, TEX
or PDFTEX environment variables in order to proceed.'

# Decide whether output auxiliary files are detected with the -recorder
# option, or by searching for \openout in the log file.
decide_aux_files_method ()
{
  # Select output file detection method
  # Valid values of TEXI2DVI_USE_RECORDER are:
  #   yes           use the -recorder option, no checks.
  #   no            scan for \openout in the log file, no checks.
  #   yesmaybe      check whether -recorder option is supported, and if yes
  #                use it, otherwise check for tracing \openout in the
  #                log file is supported, and if yes use it, else it is an 
  #                error.
  #   nomaybe      same as `yesmaybe', except that the \openout trace in
  #                log file is checked first.
  #
  #  The default behaviour is `nomaybe'.

  test -n "$TEXI2DVI_USE_RECORDER" || TEXI2DVI_USE_RECORDER=nomaybe

  case $TEXI2DVI_USE_RECORDER in
    yes) set_aux_files_from_fls;;

    no)	set_aux_files_from_log;;

    yesmaybe)
      if check_recorder_support; then
        set_aux_files_from_fls
      elif check_openout_in_log_support; then
        set_aux_files_from_log
      else
        error 1 "$aux_files_error"
      fi
      ;;

    nomaybe)
      if check_openout_in_log_support; then
        set_aux_files_from_log
      elif check_recorder_support; then
        set_aux_files_from_fls
      else
        error 1 "$aux_files_error"
      fi
      ;;
    
    *) error 1 "Invalid value of TEXI2DVI_USE_RECORDER environment variable : $TEXI2DVI_USE_RECORDER.";;

  esac
}

# remove FILE...
remove ()
{
  verbose "Removing" "$@"
  rm -rf "$@"
}


# all_files - Echo the names of all files generated, including those by
#             auxiliary tools like texindex.
all_files ()
{
  echo $in_noext.log
  echo $in_noext.fls
  echo $xref_files_new
  echo `sorted_index_files`
}

sorted_index_files ()
{
  filter_files sorted_index_filter
}

# Print the name of a generated file based on FILE if there is one.
sorted_index_filter ()
{
  case $in_lang in
    texinfo)
      # texindex: texinfo.cp -> texinfo.cps
      if test -n "`index_file_p $1`" ; then
        echo $1s
      fi
      ;;
  esac
}


# Not currently used - use with filter_files to add secondary files created by 
# bibtex
bibtex_secondary_files ()
{
  case $in_lang in
    latex)
      if test -n "`aux_file_p $1`"; then
        # bibtex: *.aux -> *.bbl and *.blg.
        echo $1 | $SED 's/^\(.*\)\.aux$/\1.bbl/'
        echo $1 | $SED 's/^\(.*\)\.aux$/\1.blg/'
      fi
      ;;
  esac
}

# mostly_clean - Remove auxiliary files and directories.  Changes back to
# the original directory.
mostly_clean ()
{
  cd_orig
  set X "$t2ddir"
  shift
  $tidy || {
    set X ${1+"$@"} `all_files`
    shift
  }
  remove ${1+"$@"}
}


# cleanup - Remove what should be removed according to options.
# Called at the end of each compilation cycle, and at the end of
# the script.  Changes the current directory.
cleanup ()
{
  case $clean:$tidy in
    true:true) mostly_clean ;;                # build mode is "clean"
    false:false) cd_orig; remove "$t2ddir";;  # build mode is "local"
  esac
}


#