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| <H1 ALIGN="CENTER">Filters</H1> |
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| <strong>Related Modules</strong><br><br> |
| |
| <a href="mod/mod_ext_filter.html">mod_ext_filter</a><br> |
| <A HREF="mod/mod_include.html">mod_include</A><br> |
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| <strong>Related Directives</strong><br><br> |
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| <a href="mod/mod_ext_filter.html#extfilterdefine">ExtFilterDefine</a></br> |
| <a href="mod/mod_ext_filter.html#extfilteroptions">ExtFilterOptions</a><br> |
| <a href="mod/core.html#setinputfilter">SetInputFilter</a><br> |
| <a href="mod/core.html#setoutputfilter">SetOutputFilter</a><br> |
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| <p>A <em>filter</em> is a process which is applied to data that is |
| sent or received by the server. Data sent by clients to the server |
| is processed by <em>input filters</em> while data sent by the |
| server to the client is processed by <em>output filters</em>. |
| Multiple filters can be applied to the data, and the order |
| of the filters can be explicitly specified.</p> |
| |
| <p>Filters are used internally by Apache to perform functions such as |
| chunking and byte-range request handling. In addition, modules can |
| provide filters which are selectable using run-time configuration |
| directives. The set of filters which apply to data can be manipulated |
| with the <code>SetInputFilter</code> and <code>SetOutputFilter</code> |
| directives.</p> |
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| <p>The only configurable filter currently included with the Apache |
| distribution is the <code>INCLUDES</code> filter which is provided by |
| <a href="mod/mod_include.html">mod_include</a> to process output for |
| Server Side Includes. There is also an experimental module called <a |
| href="mod/mod_ext_filter.html">mod_ext_filter</a> which allows for |
| external programs to be defined as filters.</p> |
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