6033N/A<!
DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
6033N/A <
TITLE>Definitions of terms used to describe Apache directives
6033N/A<!-- Background white, links blue (unvisited), navy (visited), red (active) --> 6033N/A <
H1 ALIGN="CENTER">Terms Used to Describe Apache Directives</
H1>
6033N/A Each Apache configuration directive is described using a common format
6033N/A ><
STRONG>Syntax:</
STRONG></
A> <
EM>directive-name</
EM> <
EM>some args</
EM>
6033N/A ><
STRONG>Default:</
STRONG></
A>
6033N/A <
SAMP><
EM>directive-name default-value</
EM></
SAMP>
6033N/A ><
STRONG>Context:</
STRONG></
A> <
EM>context-list</
EM>
6033N/A ><
STRONG>Override:</
STRONG></
A> <
EM>override</
EM>
6033N/A ><
STRONG>Status:</
STRONG></
A> <
EM>status</
EM>
6033N/A ><
STRONG>Module:</
STRONG></
A> <
EM>module-name</
EM>
6033N/A ><
STRONG>Compatibility:</
STRONG></
A> <
EM>compatibility notes</
EM>
6033N/A ><
STRONG>Deprecated:</
STRONG></
A> <
EM>see other</
EM>
6033N/A Each of the directive's attributes, complete with possible values
6033N/A where possible, are described in this document.
6033N/A <
LI><
A HREF="#Syntax">Syntax</
A>
6033N/A <
LI><
A HREF="#Default">Default</
A>
6033N/A <
LI><
A HREF="#Context">Context</
A>
6033N/A <
LI><
A HREF="#Override">Override</
A>
6033N/A <
LI><
A HREF="#Status">Status</
A>
6033N/A <
LI><
A HREF="#Module">Module</
A>
6033N/A <
LI><
A HREF="#Compatibility">Compatibility</
A>
6033N/A <
LI><
A HREF="#Deprecated">Deprecated</
A>
6033N/A <
H2><
A NAME="Syntax">Syntax</
A></
H2>
6033N/A This indicates the format of the directive as it would appear in a
6033N/A configuration file. This syntax is extremely directive-specific,
6033N/A and is described in detail in the directive's definition.
6033N/A Generally, the directive name is followed by a series of one or
6033N/A more space-separated arguments. If an argument contains a space,
6033N/A the argument must be enclosed in double quotes. Optional arguments
6033N/A are enclosed in square brackets. Where an argument can take on more
6033N/A than one possible value, the possible values are separated by
6033N/A vertical bars "|". Literal text is presented in the default font,
6033N/A while argument-types for which substitution is necessary are
6033N/A <
em>emphasized</
em>. Directives which can take a variable number of
6033N/A arguments will end in "..." indicating that the last argument is
6033N/A Directives use a great number of different argument types.
6033N/A A few common ones are defined below.</
p>
6033N/A<
dd>A complete Uniform Resource Locator including a scheme, hostname,
6033N/A<
dd>The part of a <
em>url</
em> which follows the scheme and hostname
6033N/Arepresents a web-view of a resource, as opposed to a file-system
6033N/A<
dd>The path to a file in the local file-system beginning with the
6033N/Aotherwise specified, a <
em>file-path</
em> which does not begin with a
6033N/Aslash will be treated as relative to the <
a 6033N/A<
dt><
em>directory-path</
em></
dt>
6033N/A<
dd>The path to a directory in the local file-system beginning with
6033N/A<
dd>The name of a file with no accompanying path information as in
6033N/A<
dd>A regular expression, which is a way of describing a pattern to
6033N/Amatch in text. The directive definition will specify what the
6033N/A<
em>regex</
em> is matching against.</
dd>
6033N/A<
dd>In general, this is the part of the <
em>filename</
em> which
6033N/Afollows the last dot. However, Apache recognizes multiple filename
6033N/Aextensions, so if a <
em>filename</
em> contains more than one dot, each
6033N/Adot-separated part of the filename following the first dot is an
6033N/A<
em>extension</
em>. For example, the <
em>filename</
em>
6033N/Aand <
code>.en</
code>. For Apache directives, you may specify
6033N/A<
em>extension</
em>s with or without the leading dot. In addition,
6033N/A<
em>extension</
em>s are not case sensitive.</
dd>
6033N/A<
dd>A method of describing the format of a file which consists of a
6033N/Amajor format type and a minor format type, separated by a slash
6033N/A<
dt><
em>env-variable</
em></
dt>
6033N/Adefined in the Apache configuration process. Note this is not
6033N/Anecessarily the same as an operating system environment variable. See
6033N/A <
H2><
A NAME="Default">Default</
A></
H2>
6033N/A If the directive has a default value (<
EM>
i.e.</
EM>, if you omit it
6033N/A from your configuration entirely, the Apache Web server will behave as
6033N/A though you set it to a particular value), it is described here. If
6033N/A there is no default value, this section should say
6033N/A "<
EM>None</
EM>". Note that the default listed here is not
6033N/A necessarily the same as the value the directive takes in the
6033N/A <
H2><
A NAME="Context">Context</
A></
H2>
6033N/A This indicates where in the server's configuration files the directive
6033N/A is legal. It's a comma-separated list of one or more of the following
6033N/A <
DT><
STRONG>server config</
STRONG>
6033N/A <
DD>This means that the directive may be used in the server
6033N/A <
STRONG>not</
STRONG> within any <
SAMP><VirtualHost></
SAMP> or
6033N/A <Directory> containers. It is not allowed in
6033N/A <
SAMP>.htaccess</
SAMP> files at all.
<
DT><
STRONG>virtual host</
STRONG>
<
DD>This context means that the directive may appear inside
<
SAMP><VirtualHost></
SAMP> containers in the server
<
DT><
STRONG>directory</
STRONG>
<
DD>A directive marked as being valid in this context may be used
inside <
SAMP><Directory></
SAMP>,
<
SAMP><Location></
SAMP>, and <
SAMP><Files></
SAMP>
containers in the server configuration files, subject to the
Location and Files sections work</
A>.
<
DT><
STRONG>.htaccess</
STRONG>
<
DD>If a directive is valid in this context, it means that it can
appear inside <
EM>per</
EM>-directory <
SAMP>.htaccess</
SAMP> files.
It may not be processed, though depending upon the
The directive is <
EM>only</
EM> allowed within the designated context;
if you try to use it elsewhere, you'll get a configuration error that
will either prevent the server from handling requests in that context
correctly, or will keep the server from operating at all --
<
EM>
i.e.</
EM>, the server won't even start.
The valid locations for the directive are actually the result of a
Boolean OR of all of the listed contexts. In other words, a directive
that is marked as being valid in "<
SAMP>server config,
.htaccess</
SAMP>" can be used in the <
SAMP>
httpd.conf</
SAMP> file
and in <
SAMP>.htaccess</
SAMP> files, but not within any
<Directory> or <VirtualHost> containers.
<
H2><
A NAME="Override">Override</
A></
H2>
This directive attribute indicates which configuration override must
be active in order for the directive to be processed when it appears
in a <
SAMP>.htaccess</
SAMP> file. If the directive's
doesn't permit it to appear in <
SAMP>.htaccess</
SAMP> files, this
attribute should say "<
EM>Not applicable</
EM>".
Overrides are activated by the
><
SAMP>AllowOverride</
SAMP></
A>
directive, and apply to a particular scope (such as a directory) and
all descendants, unless further modified by other
<
SAMP>AllowOverride</
SAMP> directives at lower levels. The
documentation for that directive also lists the possible override
<
H2><
A NAME="Status">Status</
A></
H2>
This indicates how tightly bound into the Apache Web server the
directive is; in other words, you may need to recompile the server
with an enhanced set of modules in order to gain access to the
directive and its functionality. Possible values for this attribute
<
DT><
STRONG>Core</
STRONG>
<
DD>If a directive is listed as having "Core" status, that
means it is part of the innermost portions of the Apache Web server,
<
DD>A directive labeled as having "MPM" status is
provided by a <
a href="/mpm.html">Multi-Processing Module</
a>.
This type of directive will be available if and only if you are
using one of the MPMs lised on the <
a href="#Module">Module</
a>
line of the directive definition.
<
DT><
STRONG>Base</
STRONG>
<
DD>A directive labeled as having "Base" status is
supported by one of the standard Apache modules which is compiled
into the server by default, and is therefore normally available
unless you've taken steps to remove the module from your configuration.
<
DT><
STRONG>Extension</
STRONG>
<
DD>A directive with "Extension" status is provided by one
of the modules included with the Apache server kit, but the module
isn't normally compiled into the server. To enable the directive
and its functionality, you will need to change the server build
configuration files and re-compile Apache.
<
DT><
STRONG>Experimental</
STRONG>
<
DD>"Experimental" status indicates that the directive is
available as part of the Apache kit, but you're on your own if you
try to use it. The directive is being documented for completeness,
and is not necessarily supported. The module which provides the
directive may or may not be compiled in by default; check the top of
the page which describes the directive and its module to see if it
remarks on the availability.
<
H2><
A NAME="Module">Module</
A></
H2>
This quite simply lists the name of the source module which defines
<
H2><
A NAME="Compatibility">Compatibility</
A></
H2>
If the directive wasn't part of the original Apache version 1
distribution, the version in which it was introduced should be listed
here. If the directive has the same name as one from the NCSA HTTPd
server, any inconsistencies in behaviour between the two should also
be mentioned. Otherwise, this attribute should say "<
EM>No
compatibility issues.</
EM>"
<
H2><
A NAME="Deprecated">Deprecated</
A></
H2>
If this directive is eliminated since the Apache version 1 distribution,
the directive or option that replaces the behavior should be cited here.
In general, directives, features, and options are only deprecated to
minimize debugging of conflicting features, or if the feature can only
continue to be supported in an alternate manner.