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 <H1 ALIGN="CENTER">Module mod_include</H1>

 This module is contained in the <CODE>mod_include.c</CODE> file, and
 is compiled in by default. It provides for server-parsed html
 documents. Several directives beyond the original NCSA definition were
 introduced in Apache 1.2 - these are flagged below with the phrase
 "Apache 1.2 and above".  Of particular significance are the new flow
 control directives documented at the bottom.

 <H2>Enabling Server-Side Includes</H2>

 Any document with handler of "server-parsed" will be parsed by this
 module, if the <CODE>Includes</CODE> option is set. If documents
 containing server-side include directives are given the extension
 .shtml, the following directives will make Apache parse them and
 assign the resulting document the mime type of <CODE>text/html</CODE>:

 <PRE>
 AddType text/html .shtml
 AddHandler server-parsed .shtml
 </PRE>

 The following directive must be given for the directories containing
 the shtml files (typically in a <CODE>&lt;Directory&gt;</CODE> section,
 but this directive is also valid .htaccess files if <CODE>AllowOverride
 Options</CODE> is set):

 <PRE>
 Options +Includes
 </PRE>

 Alternatively the <A HREF="#xbithack"><CODE>XBitHack</CODE></A>
 directive can be used to parse normal (<CODE>text/html</CODE>) files,
 based on file permissions.  <P>

 For backwards compatibility, documents with mime type
 <CODE>text/x-server-parsed-html</CODE> or
 <CODE>text/x-server-parsed-html3</CODE> will also be parsed
 (and the resulting output given the mime type <CODE>text/html</CODE>).

 <H2>Basic Elements</H2>

 The document is parsed as an HTML document, with special commands embedded
 as SGML comments. A command has the syntax:

 <BLOCKQUOTE><CODE>
 &lt;!--#</CODE><EM>element attribute=value attribute=value ...</EM>
 <CODE> --&gt;
 </CODE></BLOCKQUOTE>

 The value will often be enclosed in double quotes; many commands only allow
 a single attribute-value pair.  Note that the comment terminator
 (<SAMP>--&gt;</SAMP>) should be preceded by whitespace to ensure that it
 isn't considered part of an SSI token.
 <P>
 The allowed elements are:<P>

 <DL>

 <DT><STRONG>config</STRONG>
 <DD>
 This command controls various aspects of the parsing. The valid attributes
 are:
 <DL>
 <DT>errmsg
 <DD>The value is a message that is sent back to the client if an error occurs
 whilst parsing the document.
 <DT>sizefmt
 <DD>The value sets the format to be used which displaying the size of a file.
 Valid values are <CODE>bytes</CODE> for a count in bytes, or
 <CODE>abbrev</CODE> for a count in Kb or Mb as appropriate.
 <DT>timefmt
 <DD>The value is a string to be used by the <CODE>strftime(3)</CODE> library
 routine when printing dates.
 </DL>

 <A NAME="echo">
 <DT><STRONG>echo</STRONG>
 <DD>
 This command prints one of the include variables, defined below.
 If the variable is unset, it is printed as <CODE>(none)</CODE>.
 Any dates printed are subject to the currently configured <CODE>timefmt</CODE>.

 Attributes:
 <DL>
 <DT>var
 <DD>The value is the name of the variable to print.
 <DT>encoding
 <DD>Specifies how Apache should encode special characters contained
 in the variable before outputting them.  If set to "none", no encoding
 will be done.  If set to "url", then URL encoding (also known as
 %-encoding; this is appropriate for use within URLs in links, etc.)
 will be performed.  At the start of an <CODE>echo</CODE> element,
 the default is set to "entity", resulting in entity encoding (which
 is appropriate in the context of a block-level HTML element, eg.
 a paragraph of text).  This can be changed by adding an
 <CODE>encoding</CODE> attribute, which will remain in effect until
 the next <CODE>encoding</CODE> attribute is encountered or the
 element ends, whichever comes first.  Note that the
 <CODE>encoding</CODE> attribute must <EM>precede</EM> the corresponding
 <CODE>var</CODE> attribute to be effective, and that only special
 characters as defined in the ISO-8859-1 character encoding will be
 encoded.  This encoding process may not have the desired result if
 a different character encoding is in use.
 Apache 1.3.12 and above; previous versions do no encoding.

 </DL>

 <DT><STRONG>exec</STRONG>
 <DD>
 The exec command executes a given shell command or CGI script.
 The IncludesNOEXEC <A HREF="core.html#options">Option</A> disables this command
 completely. The valid attributes are:
 <DL>
 <DT>cgi
 <DD>
 The value specifies a (%-encoded) URL relative path to the CGI script.
 If the path does not begin with a (/), then it is taken to be relative to
 the current document. The document referenced by this path is invoked
 as a CGI script, even if the server would not normally recognize it as
 such. However, the directory containing the script must be enabled for
 CGI scripts (with <A HREF="mod_alias.html#scriptalias">ScriptAlias</A>
 or the ExecCGI <A HREF="core.html#options">Option</A>).<P>
 The CGI script is given the PATH_INFO and query string (QUERY_STRING) of the
 original request from the client; these cannot be specified in the URL path.
 The include variables will be available to the script in addition to the
 standard <A HREF="mod_cgi.html">CGI</A> environment.<P>
 If the script returns a Location: header instead of output, then this
 will be translated into an HTML anchor.<P>
 The <CODE>include virtual</CODE> element should be used in preference to
 <CODE>exec cgi</CODE>.
 <DT>cmd
 <DD>The server will execute the given string using <CODE>/bin/sh</CODE>.
 The include variables are available to the command.
 </DL>

 <DT><STRONG>fsize</STRONG>
 <DD>
 This command prints the size of the specified file, subject to the
 <CODE>sizefmt</CODE> format specification. Attributes:
 <DL>
 <DT>file
 <DD>The value is a path relative to the directory containing the current
 document being parsed.
 <DT>virtual
 <DD>The value is a (%-encoded) URL-path relative to the current document being
 parsed. If it does not begin with a slash (/) then it is taken to be relative
 to the current document.
 </DL>

 <DT><STRONG>flastmod</STRONG>
 <DD>
 This command prints the last modification date of the specified file,
 subject to the <CODE>timefmt</CODE> format specification. The attributes are
 the same as for the <CODE>fsize</CODE> command.

 <DT><STRONG>include</STRONG>
 <DD>
 This command inserts the text of another document or file into the parsed
 file. Any included file is subject to the usual access control. If the
 directory containing the parsed file has the
 <A HREF="core.html#options">Option</A>
 IncludesNOEXEC set, and the including the document would cause a program
 to be executed, then it will not be included; this prevents the execution of
 CGI scripts. Otherwise CGI scripts are invoked as normal using the complete
 URL given in the command, including any query string.
 <!--%plaintext &lt;?INDEX CGI scripts, {\tt include} element and&gt; -->
 <P>

 An attribute defines the location of the document; the inclusion is done for
 each attribute given to the include command. The valid attributes are:
 <DL>
 <DT>file
 <DD>The value is a path relative to the directory containing the current
 document being parsed. It cannot contain <CODE>../</CODE>, nor can it be an
 absolute path. The <CODE>virtual</CODE> attribute should always be used
 in preference to this one.
 <DT>virtual
 <DD>The value is a (%-encoded) URL relative to the current document being
 parsed. The URL cannot contain a scheme or hostname, only a path and
 an optional query string. If it does not begin with a slash (/) then it
 is taken to be relative to the current document.
 </DL>
 A URL is constructed from the attribute, and the output the server
 would return if the URL were accessed by the client is included in the parsed
 output. Thus included files can be nested.

 <DT><STRONG>printenv</STRONG>
 <DD>This prints out a listing of all existing variables and their values.
    Starting with Apache 1.3.12, special characters are entity encoded (see the
    <A HREF="#echo"><CODE>echo</CODE></A> element for details) before being
    output.  No attributes.
 <DD>For example: <CODE>&lt;!--#printenv --&gt;</CODE>
 <DD>Apache 1.2 and above.

 <DT><STRONG>set</STRONG>
 <DD>This sets the value of a variable.  Attributes:
 <DL>
 <DT>var
 <DD>The name of the variable to set.
 <DT>value
 <DD>The value to give a variable.
 </DL>
 For example:
   <CODE>&lt;!--#set var="category" value="help" --&gt;</CODE>
 <DD>Apache 1.2 and above.

 </DL>

 <H2>Include Variables</H2>

 In addition to the variables in the standard CGI environment, these are
 available for the <CODE>echo</CODE> command, for <CODE>if</CODE> and
 <CODE>elif</CODE>, and to any program invoked by the document.

 <DL>
 <DT>DATE_GMT
 <DD>The current date in Greenwich Mean Time.
 <DT>DATE_LOCAL
 <DD>The current date in the local time zone.
 <DT>DOCUMENT_NAME
 <DD>The filename (excluding directories) of the document requested by the
 user.
 <DT>DOCUMENT_URI
 <DD>The (%-decoded) URL path of the document requested by the user. Note that
 in the case of nested include files, this is <EM>not</EM> then URL for the
 current document.
 <DT>LAST_MODIFIED
 <DD>The last modification date of the document requested by the user.
 </DL>
 <P>

 <H2>Variable Substitution</H2>
 <P> Variable substitution is done within quoted strings in most cases
     where they may reasonably occur as an argument to an SSI directive.
     This includes the
     <SAMP>config</SAMP>,
     <SAMP>exec</SAMP>,
     <SAMP>flastmod</SAMP>,
     <SAMP>fsize</SAMP>,
     <SAMP>include</SAMP>, and
     <SAMP>set</SAMP>
     directives, as well as the arguments to conditional operators.
     You can insert a literal dollar sign into the string using backslash
     quoting:

 <PRE>
     &lt;!--#if expr="$a = \$test" --&gt;
 </PRE>

 <P> If a variable reference needs to be substituted in the middle of a
     character sequence that might otherwise be considered a valid
     identifier in its own right, it can be disambiguated by enclosing
     the reference in braces, <EM>&agrave; la</EM> shell substitution:

 <PRE>
     &lt;!--#set var="Zed" value="${REMOTE_HOST}_${REQUEST_METHOD}" --&gt;
 </PRE>

 <P> This will result in the <SAMP>Zed</SAMP> variable being set to
     &quot;<SAMP>X_Y</SAMP>&quot; if <SAMP>REMOTE_HOST</SAMP> is
     &quot;<SAMP>X</SAMP>&quot; and <SAMP>REQUEST_METHOD</SAMP> is
     &quot;<SAMP>Y</SAMP>&quot;.

 <P> EXAMPLE: the below example will print "in foo" if the DOCUMENT_URI is
 /foo/file.html, "in bar" if it is /bar/file.html and "in neither"
 otherwise:
 <PRE>
     &lt;!--#if expr="\"$DOCUMENT_URI\" = \"/foo/file.html\"" --&gt;
     in foo
     &lt;!--#elif expr="\"$DOCUMENT_URI\" = \"/bar/file.html\"" --&gt;
     in bar
     &lt;!--#else --&gt;
     in neither
     &lt;!--#endif --&gt;
 </PRE>

 <H2><A NAME="flowctrl">Flow Control Elements</A></H2>

 These are available in Apache 1.2 and above.  The basic flow control
 elements are:

 <PRE>
     &lt;!--#if expr="<EM>test_condition</EM>" --&gt;
     &lt;!--#elif expr="<EM>test_condition</EM>" --&gt;
     &lt;!--#else --&gt;
     &lt;!--#endif --&gt;
 </PRE>

 <P> The <STRONG><CODE>if</CODE></STRONG> element works like an
     if statement in a programming language.  The test condition
     is evaluated and if the result is true, then the text until
     the next <STRONG><CODE>elif</CODE></STRONG>, <STRONG><CODE>else</CODE></STRONG>.
     or <STRONG><CODE>endif</CODE></STRONG> element is included in the
     output stream.

 <P> The <STRONG><CODE>elif</CODE></STRONG> or <STRONG><CODE>else</CODE></STRONG>
     statements are be used the put text into the output stream
     if the original test_condition was false.  These elements
     are optional.

 <P> The <STRONG><CODE>endif</CODE></STRONG> element ends the
     <STRONG><CODE>if</CODE></STRONG> element and is required.

 <P> <EM>test_condition</EM> is one of the following:

 <DL>

 <DT><EM>string</EM><DD>true if <EM>string</EM> is not empty

 <DT><EM>string1</EM> = <EM>string2</EM>
     <BR>
     <EM>string1</EM> != <EM>string2</EM>
     <BR>
     <EM>string1</EM> &lt; <EM>string2</EM>
     <BR>
     <EM>string1</EM> &lt;= <EM>string2</EM>
     <BR>
     <EM>string1</EM> &gt; <EM>string2</EM>
     <BR>
     <EM>string1</EM> &gt;= <EM>string2</EM>

 <DD>Compare string1 with string 2.  If string2 has the form <EM>/string/</EM>
     then it is compared as a regular expression.
     Regular expressions have the same syntax as those found in the
     Unix <SAMP>egrep</SAMP> command.

 <DT>( <EM>test_condition</EM> )
         <DD>true if <EM>test_condition</EM> is true
 <DT>! <EM>test_condition</EM>
         <DD>true if <EM>test_condition</EM> is false
 <DT><EM>test_condition1</EM> && <EM>test_condition2</EM>
         <DD>true if both <EM>test_condition1</EM> and
         <EM>test_condition2</EM> are true
 <DT><EM>test_condition1</EM> || <EM>test_condition2</EM>
         <DD>true if either <EM>test_condition1</EM> or
         <EM>test_condition2</EM> is true
 </DL>

 <P> "<EM>=</EM>" and "<EM>!=</EM>" bind more tightly than "<EM>&&</EM>" and
     "<EM>||</EM>".
     "<EM>!</EM>" binds most tightly.  Thus, the following are equivalent:

 <PRE>
     &lt;!--#if expr="$a = test1 && $b = test2" --&gt;
     &lt;!--#if expr="($a = test1) && ($b = test2)" --&gt;
 </PRE>

 <P> Anything that's not recognized as a variable or an operator is
     treated as a string.  Strings can also be quoted: <EM>'string'</EM>.
     Unquoted strings can't contain whitespace (blanks and tabs)
     because it is used to separate tokens such as variables.  If
     multiple strings are found in a row, they are concatenated using
     blanks.  So,

 <PRE>
      <EM>string1    string2</EM>  results in <EM>string1 string2</EM>
     <EM>'string1    string2'</EM> results in <EM>string1    string2</EM>
 </PRE>

 <HR>
 <H2>Directives</H2>
 <UL>
 <LI><A HREF="#xbithack">XBitHack</A>
 </UL>
 <HR>


 <H2><A NAME="xbithack">XBitHack</A></H2>
 <!--%plaintext &lt;?INDEX {\tt XBitHack} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> XBitHack <EM>status</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>XBitHack off</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host, directory, .htaccess<BR>
 <A
  HREF="directive-dict.html#Override"
  REL="Help"
 ><STRONG>Override:</STRONG></A> Options<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> Base<BR>
 <A
  HREF="directive-dict.html#Module"
  REL="Help"
 ><STRONG>Module:</STRONG></A> mod_include<P>

 The XBitHack directives controls the parsing of ordinary html documents.
 This directive only affects files associated with the MIME type
 <CODE>text/html</CODE>.
 <EM>Status</EM> can have the following values:
 <DL>
 <DT>off
 <DD>No special treatment of executable files.
 <DT>on
 <DD>Any file that has the user-execute bit set will be treated as a
 server-parsed html document.
 <DT>full
 <DD>As for <CODE>on</CODE> but also test the group-execute bit. If it
 is set, then set the Last-modified date of the returned file to be the
 last modified time of the file. If it is not set, then no last-modified date
 is sent. Setting this bit allows clients and proxies to cache the result of
 the request.
 <P><STRONG>Note:</STRONG> you would not want to use this, for example, when you
 <CODE>#include</CODE> a CGI that produces different output on each hit
 (or potentially depends on the hit).
 </DL>
 <P>

 <HR>
 <H2>Using Server Side Includes for ErrorDocuments</H2>

 There is <A HREF="../misc/custom_errordocs.html">a document</A> which
 describes how to use the features of mod_include to offer internationalized
 customized server error documents.
 <P>

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 </HTML>
	<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
	<HTML>
	<HEAD>
	<TITLE>Apache module mod_include</TITLE>
	</HEAD>

	<!-- Background white, links blue (unvisited), navy (visited), red (active) -->
	<BODY
	BGCOLOR="#FFFFFF"
	TEXT="#000000"
	LINK="#0000FF"
	VLINK="#000080"
	ALINK="#FF0000"
	>
	<!--#include virtual="header.html" -->
	<H1 ALIGN="CENTER">Module mod_include</H1>

	This module is contained in the <CODE>mod_include.c</CODE> file, and
	is compiled in by default. It provides for server-parsed html
	documents. Several directives beyond the original NCSA definition were
	introduced in Apache 1.2 - these are flagged below with the phrase
	"Apache 1.2 and above". Of particular significance are the new flow
	control directives documented at the bottom.

	<H2>Enabling Server-Side Includes</H2>

	Any document with handler of "server-parsed" will be parsed by this
	module, if the <CODE>Includes</CODE> option is set. If documents
	containing server-side include directives are given the extension
	.shtml, the following directives will make Apache parse them and
	assign the resulting document the mime type of <CODE>text/html</CODE>:

	<PRE>
	AddType text/html .shtml
	AddHandler server-parsed .shtml
	</PRE>

	The following directive must be given for the directories containing
	the shtml files (typically in a <CODE><Directory></CODE> section,
	but this directive is also valid .htaccess files if <CODE>AllowOverride
	Options</CODE> is set):

	<PRE>
	Options +Includes
	</PRE>

	Alternatively the <A HREF="#xbithack"><CODE>XBitHack</CODE></A>
	directive can be used to parse normal (<CODE>text/html</CODE>) files,
	based on file permissions. <P>

	For backwards compatibility, documents with mime type
	<CODE>text/x-server-parsed-html</CODE> or
	<CODE>text/x-server-parsed-html3</CODE> will also be parsed
	(and the resulting output given the mime type <CODE>text/html</CODE>).

	<H2>Basic Elements</H2>

	The document is parsed as an HTML document, with special commands embedded
	as SGML comments. A command has the syntax:

	<BLOCKQUOTE><CODE>
	<!--#</CODE><EM>element attribute=value attribute=value ...</EM>
	<CODE> -->
	</CODE></BLOCKQUOTE>

	The value will often be enclosed in double quotes; many commands only allow
	a single attribute-value pair. Note that the comment terminator
	(<SAMP>--></SAMP>) should be preceded by whitespace to ensure that it
	isn't considered part of an SSI token.
	<P>
	The allowed elements are:<P>

	<DL>

	<DT><STRONG>config</STRONG>
	<DD>
	This command controls various aspects of the parsing. The valid attributes
	are:
	<DL>
	<DT>errmsg
	<DD>The value is a message that is sent back to the client if an error occurs
	whilst parsing the document.
	<DT>sizefmt
	<DD>The value sets the format to be used which displaying the size of a file.
	Valid values are <CODE>bytes</CODE> for a count in bytes, or
	<CODE>abbrev</CODE> for a count in Kb or Mb as appropriate.
	<DT>timefmt
	<DD>The value is a string to be used by the <CODE>strftime(3)</CODE> library
	routine when printing dates.
	</DL>

	<A NAME="echo">
	<DT><STRONG>echo</STRONG>
	<DD>
	This command prints one of the include variables, defined below.
	If the variable is unset, it is printed as <CODE>(none)</CODE>.
	Any dates printed are subject to the currently configured <CODE>timefmt</CODE>.

	Attributes:
	<DL>
	<DT>var
	<DD>The value is the name of the variable to print.
	<DT>encoding
	<DD>Specifies how Apache should encode special characters contained
	in the variable before outputting them. If set to "none", no encoding
	will be done. If set to "url", then URL encoding (also known as
	%-encoding; this is appropriate for use within URLs in links, etc.)
	will be performed. At the start of an <CODE>echo</CODE> element,
	the default is set to "entity", resulting in entity encoding (which
	is appropriate in the context of a block-level HTML element, eg.
	a paragraph of text). This can be changed by adding an
	<CODE>encoding</CODE> attribute, which will remain in effect until
	the next <CODE>encoding</CODE> attribute is encountered or the
	element ends, whichever comes first. Note that the
	<CODE>encoding</CODE> attribute must <EM>precede</EM> the corresponding
	<CODE>var</CODE> attribute to be effective, and that only special
	characters as defined in the ISO-8859-1 character encoding will be
	encoded. This encoding process may not have the desired result if
	a different character encoding is in use.
	Apache 1.3.12 and above; previous versions do no encoding.

	</DL>

	<DT><STRONG>exec</STRONG>
	<DD>
	The exec command executes a given shell command or CGI script.
	The IncludesNOEXEC <A HREF="core.html#options">Option</A> disables this command
	completely. The valid attributes are:
	<DL>
	<DT>cgi
	<DD>
	The value specifies a (%-encoded) URL relative path to the CGI script.
	If the path does not begin with a (/), then it is taken to be relative to
	the current document. The document referenced by this path is invoked
	as a CGI script, even if the server would not normally recognize it as
	such. However, the directory containing the script must be enabled for
	CGI scripts (with <A HREF="mod_alias.html#scriptalias">ScriptAlias</A>
	or the ExecCGI <A HREF="core.html#options">Option</A>).<P>
	The CGI script is given the PATH_INFO and query string (QUERY_STRING) of the
	original request from the client; these cannot be specified in the URL path.
	The include variables will be available to the script in addition to the
	standard <A HREF="mod_cgi.html">CGI</A> environment.<P>
	If the script returns a Location: header instead of output, then this
	will be translated into an HTML anchor.<P>
	The <CODE>include virtual</CODE> element should be used in preference to
	<CODE>exec cgi</CODE>.
	<DT>cmd
	<DD>The server will execute the given string using <CODE>/bin/sh</CODE>.
	The include variables are available to the command.
	</DL>

	<DT><STRONG>fsize</STRONG>
	<DD>
	This command prints the size of the specified file, subject to the
	<CODE>sizefmt</CODE> format specification. Attributes:
	<DL>
	<DT>file
	<DD>The value is a path relative to the directory containing the current
	document being parsed.
	<DT>virtual
	<DD>The value is a (%-encoded) URL-path relative to the current document being
	parsed. If it does not begin with a slash (/) then it is taken to be relative
	to the current document.
	</DL>

	<DT><STRONG>flastmod</STRONG>
	<DD>
	This command prints the last modification date of the specified file,
	subject to the <CODE>timefmt</CODE> format specification. The attributes are
	the same as for the <CODE>fsize</CODE> command.

	<DT><STRONG>include</STRONG>
	<DD>
	This command inserts the text of another document or file into the parsed
	file. Any included file is subject to the usual access control. If the
	directory containing the parsed file has the
	<A HREF="core.html#options">Option</A>
	IncludesNOEXEC set, and the including the document would cause a program
	to be executed, then it will not be included; this prevents the execution of
	CGI scripts. Otherwise CGI scripts are invoked as normal using the complete
	URL given in the command, including any query string.
	<!--%plaintext <?INDEX CGI scripts, {\tt include} element and> -->
	<P>

	An attribute defines the location of the document; the inclusion is done for
	each attribute given to the include command. The valid attributes are:
	<DL>
	<DT>file
	<DD>The value is a path relative to the directory containing the current
	document being parsed. It cannot contain <CODE>../</CODE>, nor can it be an
	absolute path. The <CODE>virtual</CODE> attribute should always be used
	in preference to this one.
	<DT>virtual
	<DD>The value is a (%-encoded) URL relative to the current document being
	parsed. The URL cannot contain a scheme or hostname, only a path and
	an optional query string. If it does not begin with a slash (/) then it
	is taken to be relative to the current document.
	</DL>
	A URL is constructed from the attribute, and the output the server
	would return if the URL were accessed by the client is included in the parsed
	output. Thus included files can be nested.

	<DT><STRONG>printenv</STRONG>
	<DD>This prints out a listing of all existing variables and their values.
	Starting with Apache 1.3.12, special characters are entity encoded (see the
	<A HREF="#echo"><CODE>echo</CODE></A> element for details) before being
	output. No attributes.
	<DD>For example: <CODE><!--#printenv --></CODE>
	<DD>Apache 1.2 and above.

	<DT><STRONG>set</STRONG>
	<DD>This sets the value of a variable. Attributes:
	<DL>
	<DT>var
	<DD>The name of the variable to set.
	<DT>value
	<DD>The value to give a variable.
	</DL>
	For example:
	<CODE><!--#set var="category" value="help" --></CODE>
	<DD>Apache 1.2 and above.

	</DL>

	<H2>Include Variables</H2>

	In addition to the variables in the standard CGI environment, these are
	available for the <CODE>echo</CODE> command, for <CODE>if</CODE> and
	<CODE>elif</CODE>, and to any program invoked by the document.

	<DL>
	<DT>DATE_GMT
	<DD>The current date in Greenwich Mean Time.
	<DT>DATE_LOCAL
	<DD>The current date in the local time zone.
	<DT>DOCUMENT_NAME
	<DD>The filename (excluding directories) of the document requested by the
	user.
	<DT>DOCUMENT_URI
	<DD>The (%-decoded) URL path of the document requested by the user. Note that
	in the case of nested include files, this is <EM>not</EM> then URL for the
	current document.
	<DT>LAST_MODIFIED
	<DD>The last modification date of the document requested by the user.
	</DL>
	<P>

	<H2>Variable Substitution</H2>
	<P> Variable substitution is done within quoted strings in most cases
	where they may reasonably occur as an argument to an SSI directive.
	This includes the
	<SAMP>config</SAMP>,
	<SAMP>exec</SAMP>,
	<SAMP>flastmod</SAMP>,
	<SAMP>fsize</SAMP>,
	<SAMP>include</SAMP>, and
	<SAMP>set</SAMP>
	directives, as well as the arguments to conditional operators.
	You can insert a literal dollar sign into the string using backslash
	quoting:

	<PRE>
	<!--#if expr="$a = \$test" -->
	</PRE>

	<P> If a variable reference needs to be substituted in the middle of a
	character sequence that might otherwise be considered a valid
	identifier in its own right, it can be disambiguated by enclosing
	the reference in braces, <EM>à la</EM> shell substitution:

	<PRE>
	<!--#set var="Zed" value="${REMOTE_HOST}_${REQUEST_METHOD}" -->
	</PRE>

	<P> This will result in the <SAMP>Zed</SAMP> variable being set to
	"<SAMP>X_Y</SAMP>" if <SAMP>REMOTE_HOST</SAMP> is
	"<SAMP>X</SAMP>" and <SAMP>REQUEST_METHOD</SAMP> is
	"<SAMP>Y</SAMP>".

	<P> EXAMPLE: the below example will print "in foo" if the DOCUMENT_URI is
	/foo/file.html, "in bar" if it is /bar/file.html and "in neither"
	otherwise:
	<PRE>
	<!--#if expr="\"$DOCUMENT_URI\" = \"/foo/file.html\"" -->
	in foo
	<!--#elif expr="\"$DOCUMENT_URI\" = \"/bar/file.html\"" -->
	in bar
	<!--#else -->
	in neither
	<!--#endif -->
	</PRE>

	<H2><A NAME="flowctrl">Flow Control Elements</A></H2>

	These are available in Apache 1.2 and above. The basic flow control
	elements are:

	<PRE>
	<!--#if expr="<EM>test_condition</EM>" -->
	<!--#elif expr="<EM>test_condition</EM>" -->
	<!--#else -->
	<!--#endif -->
	</PRE>

	<P> The <STRONG><CODE>if</CODE></STRONG> element works like an
	if statement in a programming language. The test condition
	is evaluated and if the result is true, then the text until
	the next <STRONG><CODE>elif</CODE></STRONG>, <STRONG><CODE>else</CODE></STRONG>.
	or <STRONG><CODE>endif</CODE></STRONG> element is included in the
	output stream.

	<P> The <STRONG><CODE>elif</CODE></STRONG> or <STRONG><CODE>else</CODE></STRONG>
	statements are be used the put text into the output stream
	if the original test_condition was false. These elements
	are optional.

	<P> The <STRONG><CODE>endif</CODE></STRONG> element ends the
	<STRONG><CODE>if</CODE></STRONG> element and is required.

	<P> <EM>test_condition</EM> is one of the following:

	<DL>

	<DT><EM>string</EM><DD>true if <EM>string</EM> is not empty

	<DT><EM>string1</EM> = <EM>string2</EM>
	<BR>
	<EM>string1</EM> != <EM>string2</EM>
	<BR>
	<EM>string1</EM> < <EM>string2</EM>
	<BR>
	<EM>string1</EM> <= <EM>string2</EM>
	<BR>
	<EM>string1</EM> > <EM>string2</EM>
	<BR>
	<EM>string1</EM> >= <EM>string2</EM>

	<DD>Compare string1 with string 2. If string2 has the form <EM>/string/</EM>
	then it is compared as a regular expression.
	Regular expressions have the same syntax as those found in the
	Unix <SAMP>egrep</SAMP> command.

	<DT>( <EM>test_condition</EM> )
	<DD>true if <EM>test_condition</EM> is true
	<DT>! <EM>test_condition</EM>
	<DD>true if <EM>test_condition</EM> is false
	<DT><EM>test_condition1</EM> && <EM>test_condition2</EM>
	<DD>true if both <EM>test_condition1</EM> and
	<EM>test_condition2</EM> are true
	<DT><EM>test_condition1</EM> \|\| <EM>test_condition2</EM>
	<DD>true if either <EM>test_condition1</EM> or
	<EM>test_condition2</EM> is true
	</DL>

	<P> "<EM>=</EM>" and "<EM>!=</EM>" bind more tightly than "<EM>&&</EM>" and
	"<EM>\|\|</EM>".
	"<EM>!</EM>" binds most tightly. Thus, the following are equivalent:

	<PRE>
	<!--#if expr="$a = test1 && $b = test2" -->
	<!--#if expr="($a = test1) && ($b = test2)" -->
	</PRE>

	<P> Anything that's not recognized as a variable or an operator is
	treated as a string. Strings can also be quoted: <EM>'string'</EM>.
	Unquoted strings can't contain whitespace (blanks and tabs)
	because it is used to separate tokens such as variables. If
	multiple strings are found in a row, they are concatenated using
	blanks. So,

	<PRE>
	<EM>string1 string2</EM> results in <EM>string1 string2</EM>
	<EM>'string1 string2'</EM> results in <EM>string1 string2</EM>
	</PRE>

	<HR>
	<H2>Directives</H2>
	<UL>
	<LI><A HREF="#xbithack">XBitHack</A>
	</UL>
	<HR>


	<H2><A NAME="xbithack">XBitHack</A></H2>
	<!--%plaintext <?INDEX {\tt XBitHack} directive> -->
	<A
	HREF="directive-dict.html#Syntax"
	REL="Help"
	><STRONG>Syntax:</STRONG></A> XBitHack <EM>status</EM><BR>
	<A
	HREF="directive-dict.html#Default"
	REL="Help"
	><STRONG>Default:</STRONG></A> <CODE>XBitHack off</CODE><BR>
	<A
	HREF="directive-dict.html#Context"
	REL="Help"
	><STRONG>Context:</STRONG></A> server config, virtual host, directory, .htaccess<BR>
	<A
	HREF="directive-dict.html#Override"
	REL="Help"
	><STRONG>Override:</STRONG></A> Options<BR>
	<A
	HREF="directive-dict.html#Status"
	REL="Help"
	><STRONG>Status:</STRONG></A> Base<BR>
	<A
	HREF="directive-dict.html#Module"
	REL="Help"
	><STRONG>Module:</STRONG></A> mod_include<P>

	The XBitHack directives controls the parsing of ordinary html documents.
	This directive only affects files associated with the MIME type
	<CODE>text/html</CODE>.
	<EM>Status</EM> can have the following values:
	<DL>
	<DT>off
	<DD>No special treatment of executable files.
	<DT>on
	<DD>Any file that has the user-execute bit set will be treated as a
	server-parsed html document.
	<DT>full
	<DD>As for <CODE>on</CODE> but also test the group-execute bit. If it
	is set, then set the Last-modified date of the returned file to be the
	last modified time of the file. If it is not set, then no last-modified date
	is sent. Setting this bit allows clients and proxies to cache the result of
	the request.
	<P><STRONG>Note:</STRONG> you would not want to use this, for example, when you
	<CODE>#include</CODE> a CGI that produces different output on each hit
	(or potentially depends on the hit).
	</DL>
	<P>

	<HR>
	<H2>Using Server Side Includes for ErrorDocuments</H2>

	There is <A HREF="../misc/custom_errordocs.html">a document</A> which
	describes how to use the features of mod_include to offer internationalized
	customized server error documents.
	<P>

	<!--#include virtual="footer.html" -->
	</BODY>
	</HTML>