Re: [docbook] DocBook/XML catalog question

[Thomas Schraitle <tom_schr@web.de>]

Hi,

On Monday 10 October 2005 19:55, Jeroen Ruigrok/asmodai wrote:
>
> a quick question since I help maintain DocBook/XML for pkgsrc.org.
>
> DocBook/XML 4.1.2 - 4.4 are all backwards compatible, does this mean
> that I can just add this to catalog.xml:

I wouldn't do this (see below).


> <public publicId="-//OASIS//DTD DocBook XML V4.3//EN"
>   uri="docbookx.dtd"/>
>
> <public publicId="-//OASIS//DTD DocBook XML V4.2//EN"
>   uri="docbookx.dtd"/>
>
> <public publicId="-//OASIS//DTD DocBook XML V4.1.2//EN"
>   uri="docbookx.dtd"/>
>
> This is what some people are suggesting.

Grrr. ;)


> I am a bit hesitant to do 
> this, due to the fact that if you explicitely want to validate against
> 4.1.2 or 4.2 you will have a bit wider specification if you use 4.4's
> DTD.

Your feelings are right. There are subtle changes from one version to the 
other. For example, the xml:base attribute is introduced in version 4.3 
(if I remember correct.) Documents will fail if they are validated 
against version 4.2 and below.

There are a number of possibilities to address your catalog issue. Your 
solution above is almost correct. You should just insert the correct path 
for each version.

Another possibility could be to use the delegatePublic element and handle 
the public identifier request to the original catalog:

<delegatePublic 
  publicIdStartString="-//OASIS//DTD DocBook XML V4.2//EN"
  catalog="file:///usr/share/xml/docbook/schema/dtd/4.2/catalog.xml"/>

What's better depends probably on your distribution, your configuration 
and your taste. :) For more information see [1].


Tom

--------
[1] http://www.oasis-open.org/committees/entity/spec.html

-- 
Thomas Schraitle