Why are there multiple docbook-xml ports (was: Re: Compiling gimp)

[Ryan Schmidt]

On Apr 15, 2010, at 22:57, Michael_google gmail_Gersten wrote:

> Why does it build 5 different versions of docbook?


I was hoping to be able to point you to a thread where this had been answered before, but I can't find one. I found this message where the question was asked before on the freebsd-ports mailing list, but nobody answered:

http://www.mail-archive.com/freebsd-ports@freebsd.org/msg06877.html

My understanding is that the docbook-xml-* ports provide DocBook XML DTDs -- Document Type Definitions. A DTD defines the meaning of elements within an SGML document; to read an SGML file (like a DocBook XML file), a program (like DocBook) needs the DTD referenced by the file. Any arbitrary software package FOO that builds its documentation using DocBook might have been written using any arbitrary version of the DocBook XML DTD. So we need to provide all DocBook XML DTDs still in use by any software package.