xml – DocBook：指定代码或标记

PHP中的示例使用programlisting标记,如下所示：

<programlisting language="php"><![CDATA[<?php

// Here goes the PHP code

]]></programlisting>

请注意语言属性.
稍后由另一个工具使用它来添加语法着色,在生成输出时(对于HTML输出,至少)

对于不是特定于一种编程语言的示例,例如配置文件,我们使用screen标记;例如,对于Apache相关配置文件的一部分,一个例子是：

<screen><![CDATA[# Setup Listening Port
NameVirtualHost *:80

# Ensure "localhost" is preserved unchanged pointed
# to the default document root for our system.
<VirtualHost *:80>
    ServerName localhost
    DocumentRoot /var/www
</VirtualHost>]]></screen>

引用他们的文件：

A programlisting is a verbatim
environment for program source or
source fragment listings. The
programlistings are often placed in
examples or figures so that they can
be cross-referenced from the text.

而且：

A screen is a verbatim environment for
displaying text that the user might
see on a computer terminal. It is
often used to display the results of a
command.

Having less specific semantic
overtones,screen is often used
wherever a verbatim presentation is
desired,but the semantic of
programlisting is inappropriate.

所以,这两个看起来很合适.