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DocBook Install mini-HOWTORobert B Easter reaster@reaster.com
DocBook-Install-mini-HOWTO is a detailed practical guide for novices to quickly getting DocBook installed and processing SGML files into HTML, PS, and PDF files on a GNU/Linux system - other systems may be similar. Since setup of DocBook requires files from several separately distributed packages, it can be confusing for beginners.
1. Introduction1.1. Information About this DocumentThe lastest version of this mini-HOWTO can be found at: http://www.linuxdoc.org/HOWTO/mini/DocBook-Install/ See the "Legal" section in the appendix for copyright, licenses, and disclaimer information pertaining to this document. 1.2. What is DocBookDocBook is a Standard Generalized Markup Language (SGML) Document Type Definition (DTD) that defines a set of textual document markup tags that work much like the familiar HTML language used on the web. DocBook is intended for the authoring of books and articles. As such, it provides tags specifically designed to describe books and articles. For instance, the <book> and <article> DocBook tags are used to create books and articles. Within these documents, the <chapter>, <sect1>, and <para> tags are used. DocBook SGML files are stored in text files with a sgml or gml suffix. When processed, a single DocBook SGML file can output html, pdf, ps, txt and other formats for both online and printed publication. The processing is governed by stylesheets that can automatically generate a table of contents, page numbering, chapter & section numbering, and other features. DocBook is also designed for authoring unix man pages by writing <refentry> documents. If you don't know what a man page is, try the command man man on your terminal. 1.3. Brief OverviewHere are brief descriptions of the packages we will work with in the next sections: OpenJade. OpenJade is an implementation of the ISO/IEC 10179:1996 international standard Document Style Semantics and Specification Language (DSSSL). OpenJade executes the DSSSL language to process SGML and XML input files. In particular, it uses the Modular DocBook Stylesheets dsl code to process DocBook SGML/XML files into other formats such as html, tex, rtf, txt and others. OpenJade is the essential engine for converting a DocBook file into other formats. The TeX output format is used mostly as an intermediate format to obtain dvi, pdf, and ps via TeX macros and dvi converters. DocBook SGML DTD. The DocBook Document Type Definition (DTD) files are SGML files that define the DocBook language. It defines the valid tag set and rules of their use. OpenJade requires access to the DTD files for every document type that it parses. ISO8879 ENTITY SGML. Entities define how to represent special characters that have either no keyboard key or have special meaning in SGML. Examples familiar from HTML include "&"='&', ">"='>', and "<"='<'. DocBook DSSSL (Modular DocBook Stylesheets). The DSSSL files (dsl suffix) for a particular DTD, in this case DocBook, specify how to convert DocBook into html, rtf, tex etc. A dsl file is input to openjade along with your DocBook sgml file and tells openjade how to transform/style your document into another file format. The dsl for online (html) formats is often different than for print (dvi, pdf, ps) formats. SGMLtools-Lite. SGMLtools-Lite is a frontend wrapper for running openjade and the TeX macros jadetex and pdfjadetex, macros included with OpenJade. Converting a DocBook file to ps or pdf is a two or three-step process. OpenJade outputs a tex file which is the input of jadetex to produce a dvi file, and pdfjadetex to produce a pdf. A ps file is obtained by passing the dvi file through dvips. The sgmltools script provides a single command to perform these tasks. HTMLdoc. HTMLdoc is a free program for converting html files into a pdf or ps file. SGMLSpm and docbook2X. Together, these two are used to generate man pages. SGMLSpm is a perl5 module library for processing parsed output from onsgmls, a program included with OpenJade. SGMLSpm includes an application called sgmlspl to use the SGMLSpm library. Sgmlspl requires "spec files", which are available from various other sources on the Internet, for each type of document transformation to be performed. DocBook2X is a package that provides the spec files for transforming DocBook files into man pages. 2. Download the PackagesIn this section, we will locate and download the software on the Internet. 2.1. OpenJadeOpenJade is an actively maintained open-source software project based on the Jade package by James Clark. Download the lastest stable release at: http://openjade.sourceforge.net/ OpenJade also includes the OpenSP package and the TeX macros, jadetex and pdfjadetex for converting files to dvi and pdf. The following programs are provided by this package:
To use jadetex and pdfjadetex for making dvi, ps, and pdf, you must have a working TeX (tex) installation. If you do not have TeX, check with your Linux distribution for a binary package that can be downloaded and installed. Otherwise, you can download the teTeX distribution of TeX from: 2.2. DocBook SGML DTDThe DocBook DTD for SGML and XML are maintained by a technical committee at Oasis-Open.ORG. Download the current version (and any old versions you might need) of DocBook SGML at: 2.3. ISO8879 ENTITY SGMLThe entities define representations for special or untypeable symbols or characters, including mathematical symbols, and the entities that you may be familiar with from HTML. These entity files need to be installed for a proper configuration.
ISOEnts.zip can simply be unzipped into the directory where the DocBook DTD is unzipped without requiring anything else but the files in isoENT-tar.gz are also needed. Again, the files in isoENT-tar.gz are to be unzipped into the DocBook DTD directory (see next section on installing for details), but the filenames end with ".ent" suffix. These will need to be renamed to a ".gml" ending. You can do this manually, or you can download and use the file below, made by this author, which contains the files of both ISOEnts.zip and isoENT-tar.gz: 2.4. DocBook DSSSLNorman Walsh's Document Style Semantics and Specification Language (DSSSL) files for the DocBook DTD (SGML/XML) are maintained at the DocBook Open Repository at SourceForge. These files, also known as the Modular DocBook Stylesheets, tell openjade what to do when converting your DocBook SGML file into other formats. A dsl file specifies things such as the mappings from one DTD's tags to another DTD's tags and other programmatic conversions, programmed in the DSSSL language. The DSSSL language is decomposed into a group of different languages, but running through it all is the Core Expression Language which is based on Scheme. The DocBook DSSSL package and documentation can be downloaded from the DocBook DSSSL Stylesheets Project The Linux Documentation Project has a stylesheet customization file that turns on some nice style features. It can be downloaded at: 2.5. SGMLtools-LiteSGMLtools-Lite is a frontend for openjade, jadetex, pdfjadex, dvips, and other programs. It provides a single command for generating all the formats possible with these tools. The lastest release can be downloaded at: http://sourceforge.net/projects/sgmltools-lite/ This package is optional, but does make things easier sometimes. 2.6. HTMLdocHTMLdoc is a free program for converting websites into Portable Document Format (pdf) or PostScript (ps). For pdf, it creates a tree of bookmarks that make navigation easy. Both htmldoc and pdfjadetex output pdf files, but in slightly different formats. Try both and see which turns out best for a particular docbook file. See quick links below for download site. You can download the lastest version of HTMLdoc from Easy Software Products' ftp site. 2.7. DocBook2XDocBook2X requires perl5 and the SGMLS.pm perl module, available at the Comprehensive Perl Archive Network (CPAN). SGMLS.pm provides libraries and a program called sgmlspl which translates DocBook files into other formats by using specification files. The specification files are perl files that provide the logic for the translation to a particular format. 3. Install the Packages3.1. Before You InstallThe following sections suggest how you might install the downloaded packages to setup your DocBook SGML environment. The examples may make reference to old versions of the packages but you should adapt the examples and use the most recent versions instead. For the most up-to-date, authoritative information, always read the documentation that comes with a package you are installing. Often, you will find a README and a INSTALL file after you unpack an archive. The detailed instructions below may not work exactly as shown since packages are changing all the time. However, the instructions should still give you a general idea of the procedure to get DocBook SGML working. 3.2. Install OpenJade3.2.1. openjadeHere is what to do, but remember to read the files that come with OpenJade to see if there are any things you want to do special for your platform:
You might be wondering why I dump the openjade source directly into /usr/local. The author experienced some issues with openjade's installation. However, with newer releases of OpenJade, you might try a standard (/usr/local/src) location for the openjade source package with some other prefix install location, and see how it goes. 3.2.2. jadetex & pdfjadetexAs mentioned, jadetex and pdfjadetex are TeX macros that are packaged with OpenJade. They can be found in /usr/local/openjade-3.1/dsssl. A handy guide to installing these macros was prepared by Frank Atanassow Christoph and can be found at: ftp://ftp.dante.de/tex-archive/macros/jadetex/install.pdf http://reaster.com/installjadetex.pdf The following is based on the instructions in install.pdf: 3.2.2.1. Create hugelatex (if needed)The jadetex and pdfjadetex tex macros require more memory than a regular run of tex. The default tex memory limit configuration is often too limited. The tex configuration file, texmf.cnf, can be edited and variables which limit tex's memory use can be increased. But rather than just editing the texmf.cnf file to allow tex in all instances to have more memory, a custom tex context can be created, called hugelatex. If hugelatex is already configured on your system, you can skip this subsection (which hugelatex). Verify that a working TeX is installed and find its directory:
Using which should find the location of the tex program. If its not found, then you might need to install teTeX then return here. kpsewhich is a utility that comes with teTeX and finds the main tex directory if all goes well. Now that the texmf directory is known, installation can begin:
After setting up hugelatex, like above, it may not work until the texhash program is called:
3.2.2.2. jadetex & pdfjadetexSetting up jadetex and pdfjadetex is similar to hugelatex.
The jadetex command takes a tex file generated from openjade, and outputs a dvi file. pdfjadetex takes a tex file generated from openjade, and outputs a pdf. The dvips program takes the dvi file and outputs a PostScript ps file that you can send to your printer or view with ghostscript gs. 3.3. DocBook SGML DTD3.3.1. Unpack the DocBook SGML DTDThe DocBook DTD is just some sgml text files, so there is nothing to compile. Just unzip them somewhere:
There are some differences between the different versions of the DocBook DTD. The xxissues.txt files document those issues. Tags have been added, removed, and renamed between the versions. If you need to use DocBook DTD V3.1, it is available from the same place where V4.1 is downloaded. V3.1 is used a lot, so its a good idea to get it and install it in a 3.1/ subdirectory. 3.3.2. Unpack the ISO8879 EntitiesFor each DocBook DTD version unpacked, go into its directory and unpack the iso8879-entities.tar.gz file:
3.4. DocBook DSSSLInstallation of the DocBook DSSSL, which works for all versions of DocBook, is just a matter of unzipping it somwhere.
3.5. SGMLtools-LiteIf you like it, you can install the SGMLtools-Lite, but it is optional. Its installation is the standard:
One tweak that has to be done to make the sgmltools script work, is you have to edit it and set the path to openjade: vi `which sgmltools`. Consult its docs to learn more about it. 3.6. htmldoc3.6.1. binaryPreferrably you downloaded a binary distribution of htmldoc for your platform. The installation is straightforward: just unpack it and run the setup. Read the docs in the package for more info. 3.6.2. sourceIf you downloaded the source, you will also need the Fast Light Tool Kit or else it will not link: Installation is autoconf style. Just run the configure script, make, make install. If all goes well, it will install in /usr/bin. 3.6.3. ldp_printThe htmldoc program has (or had) a few glitches when generating output from html files from openjade. For instance, bullet items are not rendered properly and shaded areas are not always shaded. To fix this problem, a perl script (ldp_print) is available from LinuxDoc.org. The lpd_print script processes a nochunks html file from openjade and then runs htmldoc on it to produce correctly rendered pdf and ps.
3.7. DocBook2X and SGMLS.pm (sgmlspl)3.7.1. sgmlsplBefore the spec files from DocBook2X are of any use, the SGMLS.pm module for perl version 5 has to be installed, assuming that perl version 5 is installed. The installation of this module is not as automated as most perl module installs. It uses a Makefile that has to be edited first before running make.
3.7.2. docbook2X (docbook2man-spec.pl)DocBook2X contains no program to compile or install, though it has some scripts you might want to look at, so all there is to do is unpack it somwhere.
3.8. $SGML_CATALOG_FILESThe $SGML_CATALOG_FILES environment variable is used by openjade (and other SGML software) to locate DTDs and DSL (stylesheets). SGML software cannot function without finding these files, which have been unpacked to various directories. Given the setup as done so far, here is how $SGML_CATALOG_FILES can be set in /etc/profile:
Installation is complete! In the next section, we'll test the installation and convert some test DocBook files. 4. Using DocBookNow that everything is installed, it's time to test it out and see how to use openjade and the other tools.
Figure 1. Example DocBook SGML file - test.sgml
DocBook: The Definitive Guide. http://www.docbook.org/tdg/en/ 4.1. Generating HTML4.1.1. docbook.dsl
Figure 2. Generating HTML output using docbook.dsl
Two htm files are generated, one for each <sect1>. The filenames are not very descriptive. Section one appears on the same page as the article information. These are the results of using the default stylesheet that comes with the Modular DocBook Stylesheets, docbook.dsl. Stylesheets can be customized to improve on these defaults. If you downloaded the Linux Documentation Project's ldp.dsl file and installed it as shown in Section 3.3, then you already have a customized style available. 4.1.2. ldp.dsl
Figure 3. Generating HTML output using ldp.dsl
Using ldp.dsl, the output looks better:
Note how the ldp.dsl file is written in the command line: it has "#html" appended. ldp.dsl contains two <STYLE-SPECIFICATION> elements, one with ID="html" and another with ID="print". This selects the html style from within ldp.dsl. The DocBook DSSSL contains support for converting DocBook files into html and print formats. In Section 3.3, we copied ldp.dsl into both the print and html directories. When generating html output, the html style should be selected like above. When generating other types of files, such as rtf and tex, they fall under the print style and so the print style should be selected from ldp.dsl. The alternative is to comment out or delete the print or html style in the copy of ldp.dsl in the respective directory. If a dsl file has more than one style-spec in it and none is selected like in the example above, then the first style encountered in the file is selected. For ldp.dsl, the print style-spec is first in the file, so it gets selected by default. So in the example above, without appending "#html" when specifying ldp.dsl as the dsssl stylesheet, the "print" style-spec would be selected and used when generating the html output. It will work, but is intended for when selecting the print/ldp.dsl and the formatting will be different. To learn more about how the stylesheet customization files are made, read the documentation for the Modular DocBook Stylesheets. Customization mainly involves setting boolean option parameters to toggle style features on and off. Completely new style logic can be programmed using the the DSSSL language. The openjade option "-t output_type" specifies the output type. The "-d dsssl_spec" option is the path to the dsssl stylesheet to use. In the example above, the output type specified is sgml, which is for SGML to SGML transformations. HTML, defined by the HTML Document Type Definition (DTD), is an SGML document type just as DocBook is, so "sgml" is the correct output_type option. The other two output types commonly used are "rtf" and "tex". The tex output_type will be used later as an intermediate format for the generation of pdf and ps formats. The dsssl_spec must specify a dsl file, not a directory. 4.2. Generating rtf and tex
4.3. Generating dvi and ps
Figure 4. Running jadetex to generate a Device Independent (dvi) file.
The first time jadetex is run, warnings are printed. They can be ignored. Running it a second time, they do not appear again.
Figure 5. Running dvips to generate a PostScript (ps) file.
Figure 6. Running htmldoc to generate a PostScript (ps) file.
4.4. Generating pdf
Figure 7. Running pdfjadetex to generate a Portable Document Format (pdf) file.
Figure 8. Running htmldoc to generate a Portable Document Format (pdf) file.
4.5. Using makeRepeating the commands to generate the output files is tedious. The make command works perfectly to automate the process.
Figure 9. Filename: Makefile - automates document generation.
Usage is just like for most projects: Figure 10. Invoking make to run Makefile
Notice the commented compile rules for pdf and ps which provide alternative means of generating those files. 4.6. Generating a man pageDuring the section on installing everything, we installed the perl version 5 module SGMLS.pm. Then we installed Docbook2X which provides the spec.pl files for transforming DocBook <refentry> documents into nroff (man page) format with sgmlspl. An example Docbook <refentry> document, for the foo command, is given below.
Figure 11. foo command man page, docbook <refentry> source (foo-ref.sgml)
Figure 12. Generating a man page with onsgmls, sgmlspl, and docbook2man-spec.pl
The man page, foo.1, is generated as a Section 1 page. The groff command is used to give a quick look at its formatted appearance. To install this man page, it belongs in any man/man1 directory, where the directory man/ is added to $MANPATH in the environment. The standard location is /usr/local/man/man1. The standard sections in the man pages system are 1 though 9. Each is for holding specific catagories of documentation. Table 1. Manual Pages Sections
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