Bug 1281 - Use a public identifier for fonts.conf
Summary: Use a public identifier for fonts.conf
Alias: None
Product: fontconfig
Classification: Unclassified
Component: library (show other bugs)
Version: 2.2
Hardware: x86 (IA32) Linux (All)
: high normal
Assignee: fontconfig-bugs
QA Contact: Behdad Esfahbod
Depends on:
Reported: 2004-09-02 14:02 UTC by Owen Taylor
Modified: 2018-08-20 21:43 UTC (History)
2 users (show)

See Also:
i915 platform:
i915 features:


Description Owen Taylor 2004-09-02 14:02:17 UTC
We have an open bug for Red Hat that the fonts.conf DTD should
be registered in the system catlog so that, e.g., psgml mode can
find it:


Sounds reasonable to me. But fontconfig currently uses:

<!DOCTYPE fontconfig SYSTEM "fonts.dtd">

Using something along the lines of:

<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"

Would make it possible. (You don't really need both the public identifier
and the URL. I think you can omit either one, but I don't know the
syntax for omitting the public identifier offhand.)
Comment 1 Keith Packard 2004-09-02 14:42:36 UTC
You're way beyond my understanding of DTDs.  Is there some formal body to
register public DTDs with?
Comment 2 Keith Packard 2005-01-28 15:56:31 UTC
I still have no idea how to make this work; can you present a more complete
recipe for this change?
Comment 3 Patrick Lam 2006-04-12 14:37:29 UTC
This seems to be a useful link:

Comment 4 Nicolas Mailhot 2006-10-29 11:54:45 UTC
As far as I know 80% of the DTDs found on the web use whatever ID their author
cooked by itself. xsd is a bit saner, you can use URIs and DNS warrants they're
Comment 5 Behdad Esfahbod 2008-08-12 16:20:55 UTC
I read the XML 1.1 spec, both the identifier and the URL are required.

Regarding public-id's, the second part of this has a formal definition of the syntax: http://xml.coverpages.org/tauber-fpi.html

There are also examples in section 1.2 of this: http://www.faqs.org/rfcs/rfc3151.html

So I suggest one of these:

-//FDO//DTD Fontconfig Font Configuration Language @DTD_VER@//EN//

+//IDN freedesktop.org//DTD Fontconfig Font Configuration Language @DTD_VER@//EN//

+//IDN fontconfig.org//DTD Font Configuration Language @DTD_VER@//EN//

Where @DTD_VER@@ is incremented everytime the DTD changes.  Copies of all versions should be available online.
Comment 6 Nicolas Mailhot 2008-12-15 11:25:39 UTC
I don't really know DTD, it is old, but I feel it does not require a resolvable URL anywhere

Fow xsds this is even more clear, take a look at "Should the targetNamespace be a URL or a URN?" on http://www.xfront.com/BestPracticesHomepage.html

When in doubt ask xml-dev on

The people here are nice and knowledgeable (they wrote the specs)
Comment 7 Nicolas Mailhot 2009-11-18 08:59:52 UTC
Looking at the catalog spec I'm not so sure it needs a different identifier. This question is probably best to ask on the xml list where people that write reference books can answer

Comment 8 GitLab Migration User 2018-08-20 21:43:16 UTC
-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

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