Re: Characters having an ASCII value > 127

Lars Marius Garshol (larsga@ifi.uio.no)
18 Sep 1998 14:44:44 +0200


* Steffen Rodig
|
| If I try to use expat on the generated XML file, it tells me that it
| is not wellformed at the position where such a character occurs.
| Does the XML spec say anything about not permitting characters with
| high ASCII values? If so, where?

It doesn't. However, the XML spec _does_ say that unless XML entities
have an XML declaration with an encoding declaration parsers are to
assume that the entity is UTF-8-encoded.

This means that if you have used ISO 8859 you may get problems, since
these characters will either be mapped to a (seemingly) random Unicode
code point or simply be invalid bit sequences that do not resolve to
any character at all.

| I guess, to correctly interpret and display those characters I have
| to know the character set which was used to encode the original text
| file.

Bingo.

| How can I communicate this character set to an XML parser?

You do this on the XML declaration, like so:

<?xml version="1.0" encoding="iso-8859-1"?>

| I would be happy if anybody could point me to somewhere I could
| start reading about this issue.

Rick Jelliffe devotes a large part of The SGML/XML Cookbook to
character sets and how they are used in XML and SGML. Other than that
I don't know of any good resources apart from good old-fashioned
digging in various places.

--Lars M.