path: root/README

NAME
    LaTeX::Driver - Latex driver

VERSION
    1.2.0

SYNOPSIS
        use LaTeX::Driver;

        $drv = LaTeX::Driver->new( source  => \$doc_text,
                                   output  => $filename,
                                   format  => 'pdf',
                                   %other_params );
        $ok    = $drv->run;
        $stats = $drv->stats;

DESCRIPTION
    The LaTeX::Driver module encapsulates the details of invoking the Latex
    programs to format a LaTeX document. Formatting with LaTeX is
    complicated; there are potentially many programs to run and the output
    of those programs must be monitored to determine whether further
    processing is required.

    This module runs the required commands in the directory specified,
    either explicitly with the "dirname" option or implicitly by the
    directory part of "basename", or in the current directory. As a result
    of the processing up to a dozen or more intermediate files are created.
    These will be removed upon object destruction, given the "cleanup"
    argument to "new".

SOURCE
    Source code can be found at <https://github.com/fordmason/LaTeX-Driver>

    Feel free to fork and add your stuff!

SUBROUTINES/METHODS
    "new(%params)"
        This is the constructor method. It creates a driver object on which
        the "run" method is used to format the document specified. The main
        arguments are "source" and "output"; the "source" argument is
        required to specify the input document; "output" is only mandatory
        if "source" is a scalar reference.

        The full list of arguments is as follows:

        "source"
            This parameter is mandatory; it can either specify the name of
            the document to be formatted or be a reference to a scalar
            containing the document source.

        "output"
            specifies the output for the formatted document; this may either
            be a file name or be a scalar reference. In the latter case the
            contents of the formatted document file is copied into the
            scalar variable referenced.

        "format"
            the format of output required: one of "dvi" (TeX Device
            Independent format), "ps" (PostScript) or "pdf" (Adobe Portable
            Document Format). The follow special values are also accepted:
            "pdf(ps)" (generates PDF via PostScript, using "dvips" and
            "ps2pdf"), "pdf(dvi)" (generates PDF via dvi, using "dvipdfm").
            If not specified then the format is determined from the name of
            the output document if specified, or defaults to PDF.

            The following list of formats is supported

            *   dvi

            *   ps

            *   postscript

            *   pdf

            *   pdf(pdflatex)

            *   pdf(xelatex)

            *   pdf(lualatex)

            *   pdf(dvi)

            *   pdf(ps)

            *   ps(pdf)

            *   ps(pdflatex)

            *   ps(xelatex)

            *   ps(lualatex)

        "tmpdir"
            Specifies whether the formatting should be done in a temporary
            directory in which case the source document is copied into the
            directory before formatting. This option can either take the
            value 1, in which case a temporary directory is automatically
            generated, or it is taken as the name of a subdirectory of the
            system temporary directory. A temporary directory is always
            created if the source document is specified as a scalar
            reference.

        "paths"
            Specifies a mapping of program names to full pathname as a hash
            reference. These paths override the paths determined at
            installation time.

        "maxruns"
            The maximum number of runs of the formatter program (defaults to
            10).

        "extraruns"
            The number of additional runs of the formatter program after the
            document has stabilized.

        "timeout"
            Specifies a timeout in seconds within which any commands spawned
            should finish.

        "cleanup"
            Specifies whether temporary files and directories should be
            automatically removed when the object destructor is called.
            Accepted values are "none" (do no cleanup), "logfiles" (remove
            log files) and "tempfiles" (remove log and temporary files). By
            default the destructor will remove the entire contents of any
            automatically generated temporary directory, but will leave all
            other files intact.

        "indexstyle"
            The name of a "makeindex" index style file that should be passed
            to "makeindex".

        "indexoptions"
            Specifies additional options that should be passed to
            "makeindex". Useful options are: "-c" to compress intermediate
            blanks in index keys, "-l" to specify letter ordering rather
            than word ordering, "-r" to disable implicit range formation.
            Refer to makeindex(1) for full details.

        "texinputs"
            Specifies one or more directories to be searched for LaTeX
            files.

        "DEBUG"
            Enables debug statements if set to a non-zero value.

        "DEBUGPREFIX"
            Sets the debug prefix, which is prepended to debug output if
            debug statements. By default there is no prefix.

        The constructor performs sanity checking on the options and will die
        if the following conditions are detected:

        *   no source is specified

        *   an invalid format is specified

        The constructor method returns a driver object.

    "run()"
        Format the document.

    "stderr"
        Holds the error output from subcommands, if the "-capture_stderr"
        option was passed to "new()".

    "stats()"
        Returns a reference to a hash containing stats about the processing
        that was performed, containing the following items:

        "pages"
            number of pages in the formatted document

        "bytes"
            number of bytes in the formatted document

        "runs"
            hash of the number of times each of the programs was run

        Note: the return value will probably become an object in a future
        version of the module.

    "program_path($program_name, $opt_value)"
        Get or set the path to the named program. Can be used as a class
        method to set the default path or as an object method to set the
        path for that instance of the driver object.

    There are a number of other methods that are used internally by the
    driver. Calling these methods directly may lead to unpredictable
    results.

    "run_latex"
        Runs the formatter ("latex" or "pdflatex").

    "need_to_run_latex"
        Determines whether the formatter needs to be run.

    "reset_latex_required"
        Reset the flags that indicate whether latex needs to be re-run
        (invoked prior to each iteration of running any necessary commands).

    "run_bibtex"
        Runs bibtex to generate the bibliography.

    "need_to_run_bibtex"
        Determines whether bibtex needs to be run.

    "run_makeindex"
        Runs makeindex to generate the index.

    "need_to_run_makeindex"
        Determines whether makeindex needs to be run.

    "run_dvips"
        Runs dvips to generate postscript output from an intermediate ".dvi"
        file.

    "run_ps2pdf"
        Runs ps2pdf to generate PDF output from an intermediate PostScript
        file.

    "run_pdf2ps"
        Runs pdf2ps to generate PostScript output from an intermediate PDF
        file.

    "run_command"
        Run a command in a controlled environment, allowing for operating
        system differences.

    "copy_to_output"
        Copy the output to its final destination.

    "throw"
        Throw an exception.

    "debug"
        Print a debug message - the caller should test $DEBUG to determine
        whether to invoke this function.

DIAGNOSTICS
    The following errors may be detected by the constructor method.

    not available on XXX
        The module is not supported on MacOS, OS/2 or VMS (or on a host of
        other operating systems but these are the only ones that are
        explicitly tested for).

    no source specified
        The "source" parameter should be specified as the name of a LaTeX
        source file or it should be a reference to a scalar variable holding
        the LaTeX source document.

    source is an invalid reference
        "source" is a reference, but not a reference to a scalar variable

    source file XXX.tex does not exist
        The source file specified does not exist

    output directory DIR does not exist
        An "output" parameter was specified as a scalar value, which was
        taken as the name of the output file, but the directory part of the
        path does not exist.

    invalid output format XXX
        An output format was specified, either explicitly or implicitly as
        the extension of the output file, but the output format specified is
        not supported.

    cannot create temporary directory
        The module could not create the temporary directory, which is used
        if the source is not specified as a filename, and the output is not
        to be left in the same directory as the source, or if a temporary
        directory name is specified explicitly.

    cannot create temporary latex file
        The module has determined that it needs to create a temporary file
        containing the source document but it cannot.

    cannot copy XXX.ext to temporary directory
        The module was trying to copy the specified source file to the
        temporary directory but couldn't. Perhaps you specified the
        temporary directory name explicitly but the directory does not exist
        or is not writeable.

    The following errors may be detected when the driver's "run()" method is
    called:

    file XXX.tex does not exist
        The source file does not exist; it may have been removed between the
        time the constructor was called and the time that the driver was
        run.

    PROGRAM exited with errors: ERRORS
        The named program ("latex" or "pdflatex") exited with the errors
        listed. You may have errors in your source file.

    bibtex FILE failed (EXITCODE)
        The "bibtex" program exited with errors. These are not fully parsed
        yet.

    failed to open BASEPATH.cit
        The driver generates its own temporary file listing the citations
        for a document, so that it can determine whether the citations have
        changed. This error indicates that it was unable to create the file.

    makeindex FILE failed (EXITCODE)
        The "makeindex" program exited with errors. These are not fully
        parsed yet.

    dvips FILE failed (EXITCODE)
        The "dvips" program exited with errors. These are not fully parsed
        yet.

    ps2pdf FILE failed (EXITCODE)
        The "ps2pdf" program exited with errors. These are not fully parsed
        yet.

    PROGNAME cannot be found, please specify its location
        The pathname for the specified program was not found in the modules
        configuration. The program may not have been found and the pathname
        not been explicitly specified when the module was installed.

    failed to copy FILE to OUTPUT
        The driver failed to copy the formatted file to the specified output
        location.

CONFIGURATION AND ENVIRONMENT
    When the using application configures Log::Any, this module will use it
    to log "debug" and "trace" level messages to the "LaTeX::Driver"
    category. Please note that the $DEBUG variable does not need to be set
    to enable this type of logging. When this type of logging is enabled,
    the value of $DEBUG is ignored.

DEPENDENCIES
    "LaTeX::Driver" depends on latex and friends being installed.

INCOMPATIBILITIES
    None known.

BUGS AND LIMITATIONS
    If you have any comments about this software I would be very grateful to
    hear them; please file your comments as issues at
    <https://github.com/Template-Toolkit-Latex/LaTeX-Driver/issues>.

    Among the things I am aware of are:

    *   I haven't worked out how I am going to deal with tex-related
        environment variables.

FUTURE DIRECTIONS
    *   Look at how path variables could be specified to the filter
        ("TEXINPUTS", "TEXINPUTS_latex", "TEXINPUTS_pdflatex", "BIBINPUTS",
        etc), and how these should interact with the system paths.

    *   Investigate pre- and post-processors and other auxiliary programs.

BACKGROUND
    This module has its origins in the original "latex" filter that was part
    of Template Toolkit prior to version 2.16. That code was fairly
    simplistic; it created a temporary directory, copied the source text to
    a file in that directory, and ran either "latex" or "pdflatex" on the
    file once; if postscript output was requested then it would run "dvips"
    after running "latex". This did not cope with documents that contained
    forward references, a table of contents, lists of figures or tables,
    bibliographies, or indexes.

    The current module does not create a temporary directory for formatting
    the document; it is given the name and location of an existing LaTeX
    document and runs the latex programs in the directory specified (the
    Template Toolkit plugin will be modified to set up a temporary
    directory, copy the source text in, then run this module, extract the
    output and remove the temporary directory).

INTERNALS
    This section is aimed at a technical audience. It documents the internal
    methods and subroutines as a reference for the module's developers,
    maintainers and anyone interesting in understanding how it works. You
    don't need to know anything about them to use the module and can safely
    skip this section.

  Formatting with LaTeX or PDFLaTeX
    LaTeX documents can be formatted with "latex" or "pdflatex"; the former
    generates a ".dvi" file (device independent - TeX's native output
    format), which can be converted to PostScript or PDF; the latter program
    generates PDF directly.

    finds inputs in "TEXINPUTS", "TEXINPUTS_latex", "TEXINPUTS_pdflatex",
    etc

  Generating indexes
    The standard program for generating indexes is "makeindex", is a general
    purpose hierarchical index generator. "makeindex" accepts one or more
    input files (".idx"), sorts the entries, and produces an output (".ind")
    file which can be formatted.

    The style of the generated index is specified by a style file (".ist"),
    which is found in the path specified by the "INDEXSTYLE" environment
    variable.

    An alternative to "makeindex" is "xindy", but that program is not
    widespread yet.

  Generating bibliographies with BiBTeX
    BiBTeX generates a bibliography for a LaTeX document. It reads the
    top-level auxiliary file (".aux") output during the running of latex and
    creates a bibliography file (".bbl") that will be incorporated into the
    document on subsequent runs of latex. It looks up the entries specified
    by \cite and \nocite commands in the bibliographic database files (.bib)
    specified by the \bibliography commands. The entries are formatted
    according to instructions in a bibliography style file (".bst"),
    specified by the \bibliographystyle command.

    Bibliography style files are searched for in the path specified by the
    "BSTINPUTS" environment variable; for bibliography files it uses the
    "BIBINPUTS" environment variable. System defaults are used if these
    environment variables are not set.

  Running Dvips
    The "dvips" program takes a DVI file produced by TeX and converts it to
    PostScript.

  Running ps2pdf
    The "ps2pdf" program invokes Ghostscript to converts a PostScript file
    to PDF.

  Running on Windows
    Commands are executed with "cmd.exe". The syntax is:

       cmd /c "cd $dir && $program $args"

    This changes to the specified directory and executes the program there,
    without affecting the working directory of the the Perl process.

    Need more information on how to set environment variables for the
    invoked programs.

  Miscellaneous Information
    This is a placeholder for information not yet incorporated into the rest
    of the document.

    May want to mention the kpathsea library, the "kpsewhich" program, the
    web2c TeX distribution, TeX live, tetex, TeX on Windows, etc.

AUTHOR
       Erik Huelsmann  <erik@efficito.com>  (current maintainer)

LICENSE AND COPYRIGHT
       Copyright (C) 2020  Erik Huelsmann.
       Copyright (C) 2014  Chris Travers.
       Copyright (C) 2009-2013 Ford & Mason Ltd.
       Copyright (C) 2006-2007 Andrew Ford.
       Portions Copyright (C) 1996-2006 Andy Wardley.

    This module is free software; you can redistribute it and/or modify it
    under the same terms as Perl itself.

SEE ALSO
    Template::Plugin::Latex, latex(1), makeindex(1), bibtex(1), dvips(1),
    The dvips manual

    There are a number of books and other documents that cover LaTeX:

    *   The LaTeX Companion

    *   Web2c manual