What is a "Public Identifier"?

[Lars Marius Garshol]

* Mike Spreitzer
|
| I'm wondering if there is any standardization of what's in a "public
| identifier" 

The SGML standard (ISO 8879) defines something called a 'formal public
identifier' (clause 10.2), but whether public identifiers must be FPIs
or not is defined by the SGML declaration used.

In other words: public identifiers can be whatever you want, but you
can declare them to be FPIs.

The FPI syntax is described with BNF at

<URL:http://www.tiac.net/users/bingham/sgmlsyn/sgmlsyn.htm#P79>

| and/or of how one is resolved to whatever it refers to.

The usual way to resolve a public identifier is to use a so-called
catalog file. Currently there are two syntaxes for catalog files SGML
Open Catalog files (supported by lots of SGML tools plus DXP and
xmlproc) and XCatalogs (supported by xmlproc).

<URL:http://www.sgmlopen.org/html/a401.htm>
<URL:http://www.ccil.org/~cowan/XML>

| Yet there is a lot of regularity in the examples I see.  I've never
| seen anything specifying the structure used.  What am I missing?

Clause 10.2 of the ISO 8879 standard. The best place to get hold of it
is Goldfarbs The SGML Handbook, which has a lot of explanatory text
supplementing the standard itself.

--Lars M.


xml-dev: A list for W3C XML Developers. To post, mailto:xml-dev at ic.ac.uk
Archived as: http://www.lists.ic.ac.uk/hypermail/xml-dev/
To (un)subscribe, mailto:majordomo at ic.ac.uk the following message;
(un)subscribe xml-dev
To subscribe to the digests, mailto:majordomo at ic.ac.uk the following message;
subscribe xml-dev-digest
List coordinator, Henry Rzepa (mailto:rzepa at ic.ac.uk)