Related Modules mod_defalte mod_ext_filter mod_include |
Related Directives AddInputFilter AddOutputFilter ExtFilterDefine ExtFilterOptions SetInputFilter SetOutputFilter |
A filter is a process that is applied to data that is sent or received by the server. Data sent by clients to the server is processed by input filters while data sent by the server to the client is processed by output filters. Multiple filters can be applied to the data, and the order of the filters can be explicitly specified.
Filters are used internally by Apache to perform functions such
as chunking and byte-range request handling. In addition, modules
can provide filters that are selectable using run-time
configuration directives. The set of filters that apply to data
can be manipulated with the SetInputFilter
,
SetOutputFilter
, AddInputFilter
, and
AddOutputFilter
directives.
The following user-selectable filters are currently provided with the Apache HTTP Server distribution.
In addition, the module mod_ext_filter allows for external programs to be defined as filters.