apache-http-server/docs/manual/mod/mod_charset_lite.xml

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<modulesynopsis metafile="mod_charset_lite.xml.meta">

<name>mod_charset_lite</name>
<description>Specify character set translation or recoding</description>
<status>Extension</status>
<sourcefile>mod_charset_lite.c</sourcefile>
<identifier>charset_lite_module</identifier>

<summary>
    <p><module>mod_charset_lite</module> allows the server to change
    the character set of responses before sending them to the client.
    In an EBCDIC environment, Apache always translates HTTP protocol
    content (e.g. response headers) from the code page of the Apache
    process locale to ISO-8859-1, but not the body of responses.  In
    any environment, <module>mod_charset_lite</module> can be used to
    specify that response bodies should be translated.  For example,
    if files are stored in EBCDIC, then
    <module>mod_charset_lite</module> can translate them to
    ISO-8859-1 before sending them to the client.</p>

    <p>This module provides a small subset of configuration
    mechanisms implemented by Russian Apache and its associated
    <code>mod_charset</code>.</p>
</summary>

<section id="problems"><title>Common Problems</title>

    <section><title>Invalid character set names</title>

      <p>The character set name parameters of <directive
      module="mod_charset_lite">CharsetSourceEnc</directive> and
      <directive module="mod_charset_lite">CharsetDefault</directive>
      must be acceptable to the translation mechanism used by
      <glossary>APR</glossary> on the system where
      <module>mod_charset_lite</module> is deployed.  These character
      set names are not standardized and are usually not the same as
      the corresponding values used in http headers.  Currently, APR
      can only use iconv(3), so you can easily test your character set
      names using the iconv(1) program, as follows:</p>

      <example>
        iconv -f charsetsourceenc-value -t charsetdefault-value
      </example>
    </section>

    <section><title>Mismatch between character set of content and translation
    rules</title>

      <p>If the translation rules don't make sense for the content,
      translation can fail in various ways, including:</p>

      <ul>
      <li>The translation mechanism may return a bad return code,
      and the connection will be aborted.</li>

      <li>The translation mechanism may silently place special
      characters (e.g., question marks) in the output buffer when
      it cannot translate the input buffer.</li>
      </ul>
    </section>
</section>

<directivesynopsis>
<name>CharsetSourceEnc</name>
<description>Source charset of files</description>
<syntax>CharsetSourceEnc <var>charset</var></syntax>
<contextlist><context>server config</context>
<context>virtual host</context><context>directory</context>
<context>.htaccess</context>
</contextlist>
<override>FileInfo</override>

<usage>
    <p>The <directive>CharsetSourceEnc</directive> directive specifies the
    source charset of files in the associated container.</p>

    <p>The value of the <var>charset</var> argument must be accepted
    as a valid character set name by the character set support in
    <glossary>APR</glossary>. Generally, this means that it must be
    supported by iconv.</p>

    <example><title>Example</title>
    <highlight language="config">
&lt;Directory "/export/home/trawick/apacheinst/htdocs/convert"&gt;
    CharsetSourceEnc  UTF-16BE
    CharsetDefault    ISO-8859-1
&lt;/Directory&gt;
      </highlight>
    </example>

    <p>The character set names in this example work with the iconv
    translation support in Solaris 8.</p>

     <note>
     Specifying the same charset for both <directive module="mod_charset_lite">CharsetSourceEnc</directive>
     and <directive module="mod_charset_lite">CharsetDefault</directive> disables translation. The charset
     need not match the charset of the response, but it must be a valid charset on the system.
     </note>

</usage>
</directivesynopsis>

<directivesynopsis>
<name>CharsetDefault</name>
<description>Charset to translate into</description>
<syntax>CharsetDefault <var>charset</var></syntax>
<contextlist><context>server config</context>
<context>virtual host</context><context>directory</context>
<context>.htaccess</context>
</contextlist>
<override>FileInfo</override>

<usage>
    <p>The <directive>CharsetDefault</directive> directive specifies the
    charset that content in the associated container should be
    translated to.</p>

    <p>The value of the <var>charset</var> argument must be accepted
    as a valid character set name by the character set support in
    <glossary>APR</glossary>. Generally, this means that it must be
    supported by iconv.</p>

    <example><title>Example</title>
    <highlight language="config">
&lt;Directory "/export/home/trawick/apacheinst/htdocs/convert"&gt;
    CharsetSourceEnc  UTF-16BE
    CharsetDefault    ISO-8859-1
&lt;/Directory&gt;
      </highlight>
    </example>

     <note>
     Specifying the same charset for both <directive module="mod_charset_lite">CharsetSourceEnc</directive>
     and <directive module="mod_charset_lite">CharsetDefault</directive> disables translation. The charset
     need not match the charset of the response, but it must be a valid charset on the system.
     </note>

</usage>
</directivesynopsis>

<directivesynopsis>
<name>CharsetOptions</name>
<description>Configures charset translation behavior</description>
<syntax>CharsetOptions <var>option</var> [<var>option</var>] ...</syntax>
<default>CharsetOptions ImplicitAdd</default>
<contextlist><context>server config</context>
<context>virtual host</context><context>directory</context>
<context>.htaccess</context>
</contextlist>
<override>FileInfo</override>

<usage>
    <p>The <directive>CharsetOptions</directive> directive configures certain
    behaviors of <module>mod_charset_lite</module>. <var>Option</var> can
    be one of</p>

    <dl>
      <dt><code>ImplicitAdd | NoImplicitAdd</code></dt>

      <dd>The <code>ImplicitAdd</code> keyword specifies that
      <module>mod_charset_lite</module> should implicitly insert its
      filter when the configuration specifies that the character
      set of content should be translated. If the filter chain is
      explicitly configured using the <directive module="mod_mime"
      >AddOutputFilter</directive> directive, <code>NoImplicitAdd</code>
      should be specified so that <module>mod_charset_lite</module>
      doesn't add its filter.</dd>

      <dt><code>TranslateAllMimeTypes | NoTranslateAllMimeTypes</code></dt>
      <dd>Normally, <module>mod_charset_lite</module> will only perform
      translation on a small subset of possible mimetypes.  When the
      <code>TranslateAllMimeTypes</code> keyword is specified for a given
      configuration section, translation is performed without regard for
      mimetype.</dd>

    </dl>
</usage>
</directivesynopsis>

</modulesynopsis>