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Debian doc-base Manual
Chapter 2 - The packages interface

2.1 Introduction

Each Debian package that installs online manuals (any format) should register its manuals to doc-base. This is done by installing a doc-base control file and calling install-docs from the postinst script.

2.2 Document ids

Each piece of online documentation that is registered to doc-base must have an unique document id.

The document id is usually taken from the document's title or from the package name. Here are a few examples:

     DOCID                  Title
     ---------------------- ----------------------------
     debian-policy          Debian Policy Manual
     developers-reference   Debian Developers Reference
     doc-base               Debian doc-base Manual
     emacs-manual           GNU Emacs Manual

Just as package names, the document id may only consist lower case letters (a-z), digits (0-9), plus (+) or minus (-) signs, and dots (.).

2.3 Control files

For each piece online documentation, doc-base needs a control file that describes the documentation and the documentation file formats that are provided initially.

Here is an example of a control file:

     Document: doc-base
     Title: Debian doc-base Manual
     Author: Christian Schwarz
     Abstract: This manual describes what doc-base is
      and how it can be used to
      manage online manuals on Debian systems.
     Section: Apps/Programming
     
     Format: debiandoc-sgml
     Files: /usr/doc/doc-base/doc-base.sgml.gz
     
     Format: text
     Files: /usr/doc/doc-base/doc-base.text.gz
     
     Format: HTML
     Index: /usr/doc/doc-base/doc-base.html/index.html
     Files: /usr/doc/doc-base/doc-base.html/*.html

As you can see from this example, the syntax--just as the whole design of doc-base--is heavily influenced by dpkg. This is important since every maintainer will have to work with doc-base and thus, it should be simply to remember the basic ideas.

The syntax of the control file is simple: Empty lines seperate sections (see below). The other line use a field-value syntax. Field values may be wrapped over several lines if the first character of subsequent lines is a space; if the value should contain an empty line a single dot (.) has to be placed in the second column. The field names are case-insensitive.

The first section of the control file describes the document, starting with the document id (the `Document:' field), the title, etc. This information will be used when the manual is registered to the online menu systems (dhelp, dwww, etc.).

The following sections describe the different formats which are provided by the package. This information will be needed when the format-conversion feature is implemented. (Note, that these fields are likely to be changed as soon as I start with the implementation.)

For now, only the format `HTML' is recognized. The `Index:' field has to contain the absolute file name of the title page of the document. (This file will be specified as front page link when the document is registered to dwww or dhelp.)

2.4 Registering documents using install-docs

In order to register a piece of online documentation to doc-base, the package has to install the control file (see above) as file /usr/share/doc-base/document-id.

Then, it should call install-docs from its postinst script:

       if [ "$1" = configure ]; then
         if command -v install-docs >/dev/null 2>&1; then
           install-docs -i /usr/share/doc-base/<document-id>
         fi
       fi

and from the prerm script as well:

       if [ "$1" = remove -o "$1" = upgrade ]; then
         if command -v install-docs >/dev/null 2>&1; then
           install-docs -r <document-id>
         fi
       fi

With that, doc-base will automatically register the online manuals to dwww and dhelp when the package is installed, and de-register the manuals when the package is removed.

Note that the call to remove the registered documentation from the prerm maintainer script is necessary for cases such as when the documentation directory changes and you want to avoid messages such as

     dpkg: warning - unable to delete old file `directory': Directory not empty

Debian doc-base Manual