DOCBOOK-APPS: DTD vs. XML Schema

["Olson, Dave -Systems" <Dave dot Olson at itt dot com>]

Could someone give me a list of the advantages and disadvantages of using
the DocBook DTD(s) vs. a DocBook XML Schema?  I'm just starting a
documentation conversion project, using Cocoon (Xalan is XSLT engine).  I've
never used either a DTD or XML Schema, so using either form of XML
technology involves a learning curve.  I'd like to stay with free tools.  I
understand PSGML with emacs is a validating editor, but it doesn't work with
Schemas.  Are there tools available to edit DocBook XML via an XML Schema?

I'll also be searching for stylesheets to convert DocBook XML files to our
output formats (PDF, HTML, RTF), but if I understand the application of the
DocBook standard correctly, the stylesheets shouldn't be affected by whether
I use a DTD or a Schema as my guide.  The main reason I'm choosing between
the two is that I will probably want to customize the document definition
and stylesheets, and I hear the Schema is more flexible and easier to read.

David Olson
Transportation Simulation and Systems Department
ITT Industries, Inc., Systems Division
Colorado Springs, Colorado


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