Re: Unable to use DocBook PNG Variant

[Dan Mueth <d-mueth uchicago edu>]

Hi Liam,

> I'm still having difficulties using the DocBook PNG Variant DTD (the
> standard DocBook 3.1 DTD works fine). My SGML document begins:
> 
> <!DOCTYPE Article PUBLIC "-//GNOME//DTD DocBook PNG Variant V1.0//EN" [
> 
> When I try to validate, I receive the following error message:
> 
> nsgmls:color_picker.sgml:1:70:W: cannot generate system identifier for
> public text "-//GNOME//DTD DocBook PNG Variant V1.0//EN"
> 
> png-support-3.1.dtd is located in both /usr/share/sgml/gnome/ and
> /usr/lib/sgml/. docbook.dtd is located in /usr/lib/sgml/.
> 
> The last lines in /usr/lib/sgml/CATALOG are:
> 
> PUBLIC  "-//GNOME//DTD DocBook PNG Variant V1.0//EN"
> 	"png-support-3.1.dtd"
> CATALOG "/var/lib/sgml/CATALOG.docbk31"
> CATALOG "/var/lib/sgml/CATALOG.docbk30"

This looks pretty good to me.  I don't know if this would matter, but we
generally use V1.0 for png-support-3.0.dtd and V1.1 for the 3.1 dtd:

--for DocBook 3.0--
PUBLIC "-//GNOME//DTD DocBook PNG Variant V1.0//EN" "png-support-3.0.dtd"
--for DocBook 3.1--
PUBLIC "-//GNOME//DTD DocBook PNG Variant V1.1//EN" "png-support-3.1.dtd"

It looks like the header on png-support-3.1.dtd was not updated to
increment V1.0 to V1.1.

Dan