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 <H1 ALIGN="CENTER">Module mod_log_config</H1>
 <P>
 This module is contained in the <CODE>mod_log_config.c</CODE> file,
 and is compiled in by default in Apache 1.2. mod_log_config replaces
 mod_log_common in Apache 1.2. Prior to version 1.2, mod_log_config was
 an optional module. It provides for logging of the requests made to
 the server, using the Common Log Format or a user-specified format.
 </P>

 <H2>Summary</H2>
 <P>
 Three directives are provided by this module: <CODE>TransferLog</CODE>
 to create a log file, <CODE>LogFormat</CODE> to set a custom format,
 and <CODE>CustomLog</CODE> to define a log file and format in one go.
 The <CODE>TransferLog</CODE> and <CODE>CustomLog</CODE> directives can
 be used multiple times in each server to cause each request to be
 logged to multiple files.
 </P>

 <H3>Compatibility notes</H3>

 <UL>
 <LI>This module is based on mod_log_config distributed with
 previous Apache releases, now updated to handle multiple logs.
 There is now no need to re-configure Apache to use configuration log
 formats.

 <LI>The module also implements the <CODE>CookieLog</CODE> directive,
 used to log user-tracking information created by <A
 HREF="mod_usertrack.html">mod_usertrack</A>. The use of
 <CODE>CookieLog</CODE> is deprecated, and a <CODE>CustomLog</CODE>
 should be defined to log user-tracking information instead.

 <LI>As of Apache 1.3.5, this module allows conditional logging
 based upon the setting of environment variables.  That is,
 you can control whether a request should be logged or not
 based upon whether an arbitrary environment variable is
 defined or not.  This is settable on a <EM>per</EM>-logfile
 basis.

 <LI>Beginning with Apache 1.3.5, the mod_log_config module has
 also subsumed the <CODE>RefererIgnore</CODE> functionality from
 <A HREF="mod_log_referer.html">mod_log_referer</A>.  The effect
 of <CODE>RefererIgnore</CODE> can be achieved by combinations of
 <A HREF="mod_setenvif.html"><CODE>SetEnvIf</CODE></A> directives
 and conditional <CODE>CustomLog</CODE> definitions.

 </UL>

 <H2>Log File Formats</H2>

 Unless told otherwise with <TT>LogFormat</TT> the log files created by
 <TT>TransferLog</TT> will be in standard "Common Log Format"
 (CLF). The contents of each line in a CLF file are explained
 below. Alternatively, the log file can be customized (and if multiple
 log files are used, each can have a different format). Custom formats
 are set with <CODE>LogFormat</CODE> and <CODE>CustomLog</CODE>.

 <H3>Common Log Format</H3>

 The Common Log Format (CLF) file contains a separate line for each
 request. A line is composed of several tokens separated by spaces:

 <BLOCKQUOTE>
 host ident authuser date request status bytes
 </BLOCKQUOTE>
 If a token does not have a value then it is represented by a hyphen (-).
 The meanings and values of these tokens are as follows:
 <DL>
 <DT>host
 <DD>The fully-qualified domain name of the client, or its IP number if the
 name is not available.
 <DT>ident
 <DD>If <A HREF="core.html#identitycheck">IdentityCheck</A> is enabled and the
 client machine runs identd, then this is the identity information reported
 by the client.
 <DT>authuser
 <DD>If the request was for an password protected document, then this is
 the userid used in the request.
 <DT>date
 <DD>The date and time of the request, in the following format:
 <DL><DD><BLOCKQUOTE><CODE> date = [day/month/year:hour:minute:second zone] <BR>
 day = 2*digit<BR>
 month = 3*letter<BR>
 year = 4*digit<BR>
 hour = 2*digit<BR>
 minute = 2*digit<BR>
 second = 2*digit<BR>
 zone = (`+' | `-') 4*digit</CODE></BLOCKQUOTE></DL>
 <DT>request
 <DD>The request line from the client, enclosed in double quotes
 (<CODE>&quot;</CODE>).
 <DT>status
 <DD>The three digit status code returned to the client.
 <DT>bytes
 <DD>The number of bytes in the object returned to the client, not including
 any headers.
 </DL>

 <H3><A NAME="formats">Custom Log Formats</A></H3>

 The format argument to the <CODE>LogFormat</CODE> and
 <CODE>CustomLog</CODE> is a string. This string is logged to the log
 file for each request. It can contain literal characters copied into
 the log files, and `%' directives which are replaced in the log file
 by the values as follows:

 <PRE>
 %...a:          Remote IP-address
 %...A:          Local IP-address
 %...B:          Bytes sent, excluding HTTP headers.
 %...b:          Bytes sent, excluding HTTP headers. In CLF format
 		i.e. a '-' rather than a 0 when no bytes are sent.
 %...{FOOBAR}e:  The contents of the environment variable FOOBAR
 %...f:          Filename
 %...h:          Remote host
 %...H		The request protocol
 %...{Foobar}i:  The contents of Foobar: header line(s) in the request
                 sent to the server.
 %...l:          Remote logname (from identd, if supplied)
 %...m		The request method
 %...{Foobar}n:  The contents of note "Foobar" from another module.
 %...{Foobar}o:  The contents of Foobar: header line(s) in the reply.
 %...p:          The canonical Port of the server serving the request
 %...P:          The process ID of the child that serviced the request.
 %...q		The query string (prepended with a ? if a query string exists,
 		otherwise an empty string)
 %...r:          First line of request
 %...s:          Status.  For requests that got internally redirected, this is
                 the status of the *original* request --- %...&gt;s for the last.
 %...t:          Time, in common log format time format (standard english format)
 %...{format}t:  The time, in the form given by format, which should
                 be in strftime(3) format. (potentially localised)
 %...T:          The time taken to serve the request, in seconds.
 %...u:          Remote user (from auth; may be bogus if return status (%s) is 401)
 %...U:          The URL path requested.
 %...v:          The canonical ServerName of the server serving the request.
 %...V:          The server name according to the UseCanonicalName setting.
 </PRE>

 The `...' can be nothing at all (<EM>e.g.</EM>, <CODE>"%h %u %r %s %b"</CODE>), or it can
 indicate conditions for inclusion of the item (which will cause it
 to be replaced with `-' if the condition is not met).  Note that
 there is no escaping performed on the strings from %r, %...i and
 %...o; some with long memories may remember that I thought this was
 a bad idea, once upon a time, and I'm still not comfortable with
 it, but it is difficult to see how to `do the right thing' with all
 of `%..i', unless we URL-escape everything and break with CLF.

 <P>

 The forms of condition are a list of HTTP status codes, which may
 or may not be preceded by `!'.  Thus, `%400,501{User-agent}i' logs
 User-agent: on 400 errors and 501 errors (Bad Request, Not
 Implemented) only; `%!200,304,302{Referer}i' logs Referer: on all
 requests which did <STRONG>not</STRONG> return some sort of normal status.

 <P>

 Note that the common log format is defined by the string <CODE>"%h %l
 %u %t \"%r\" %s %b"</CODE>, which can be used as the basis for
 extending for format if desired (<EM>e.g.</EM>, to add extra fields at the end).
 NCSA's extended/combined log format would be <CODE>"%h %l %u %t \"%r\" %s %b \"%{Referer}i\" \"%{User-agent}i\""</CODE>.

 <P>

 Note that the canonical <A HREF="core.html#servername">ServerName</A>
 and <A HREF="core.html#port">Port</A> of the server serving the request
 are used for <CODE>%v</CODE> and <CODE>%p</CODE> respectively.  This
 happens regardless of the
 <A HREF="core.html#usecanonicalname">UseCanonicalName</A> setting because
 otherwise log analysis programs would have to duplicate the entire
 vhost matching algorithm in order to decide what host really served
 the request.

 <H2>Using Multiple Log Files</H2>

 The <CODE>TransferLog</CODE> and <CODE>CustomLog</CODE> directives can
 be given more than once to log requests to multiple log files. Each
 request will be logged to all the log files defined by either of these
 directives.

 <H3>Use with Virtual Hosts</H3>

 If a &lt;VirtualHost&gt; section does not contain any
 <TT>TransferLog</TT> or <TT>CustomLog</TT> directives, the
 logs defined for the main server will be used. If it does
 contain one or more of these directives, requests serviced by
 this virtual host will only be logged in the log files defined
 within its definition, not in any of the main server's log files.
 See the examples below.
 <P>

 <H2>Security Considerations</H2>

 See the <A HREF="../misc/security_tips.html#security">security tips</A>
 document for details on why your security could be compromised if the
 directory where logfiles are stored is writable by anyone other than
 the user that starts the server.
 <P>
 <H2>Directives</H2>

 <UL>
 <LI><A HREF="#cookielog">CookieLog</A>
 <LI><A HREF="#customlog">CustomLog</A>
 <LI><A HREF="#customlog-conditional">CustomLog (conditional)</A>
 <LI><A HREF="#logformat">LogFormat</A>
 <LI><A HREF="#transferlog">TransferLog</A>
 </UL>
 <HR>


 <H2><A NAME="cookielog">CookieLog</A></H2>
 <!--%plaintext &lt;?INDEX {\tt CookieLog} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> CookieLog <EM>filename</EM><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Module"
  REL="Help"
 ><STRONG>Module:</STRONG></A> mod_cookies<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> Only available in Apache 1.2 and above<P>

 The CookieLog directive sets the filename for logging of cookies.
 The filename is relative to the <A
 HREF="core.html#serverroot">ServerRoot</A>. This directive is included
 only for compatibility with
 <A HREF="mod_cookies.html">mod_cookies</A>, and is deprecated.
 <P>

 <HR>
 <H2><A NAME="customlog">CustomLog</A></H2>
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> CustomLog <EM>file-pipe</EM>
     <EM>format-or-nickname</EM><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> Base<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> Nickname only available in Apache 1.3
     or later
 <BR>
 <A
  HREF="directive-dict.html#Module"
  REL="Help"
 ><STRONG>Module:</STRONG></A> mod_log_config
 <P>
 The first argument is the filename to which log records should be
 written. This is used
 exactly like the argument to
 <A
  HREF="#transferlog"
 ><SAMP>TransferLog</SAMP></A>;
 that is, it is either a full path or relative to the current
 server root.
 </P>
 <P>
 The format argument specifies a format for each line of the log file.
 The options available for the format are exactly the same as for
 the argument of the <TT>LogFormat</TT> directive. If the format
 includes any spaces (which it will do in almost all cases) it
 should be enclosed in double quotes.
 </P>
 <P>
 Instead of an actual format string, you can use a format nickname defined with
 the
 <A
  HREF="#logformat"
 ><SAMP>LogFormat</SAMP></A>
 directive.
 </P>

 <HR>
 <H2><A NAME="customlog-conditional">CustomLog (conditional)</A></H2>
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> CustomLog <EM>file-pipe</EM>
     <EM>format-or-nickname</EM>
     env=[!]<EM>environment-variable</EM><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> Base<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> Only available in Apache 1.3.5
     or later
 <BR>
 <A
  HREF="directive-dict.html#Module"
  REL="Help"
 ><STRONG>Module:</STRONG></A> mod_log_config
 <P>

 The behaviour of this form of the <SAMP>CustomLog</SAMP> directive is almost
 identical to the <A HREF="#customlog">standard <CODE>CustomLog</CODE></A>
 directive.  The difference is that the '<CODE>env=</CODE>' clause controls
 whether a particular request will be logged in the specified file or
 not.  If the specified environment variable is set for the
 request (or is not set, in the case of a '<CODE>env=!<EM>name</EM></CODE>'
 clause), then the request will be logged.
 </P>
 <P>
 Environment variables can be set on a <EM>per</EM>-request basis
 using the <A HREF="mod_setenvif.html">mod_setenvif</A> and/or
 <A HREF="mod_rewrite.html">mod_rewrite</A> modules.  For example,
 if you don't want to record requests for all GIF images on
 your server in a separate logfile but not your main log, you
 can use:
 </P>
 <PRE>
     SetEnvIf Request_URI \.gif$ gif-image
     CustomLog gif-requests.log common env=gif-image
     CustomLog nongif-requests.log common env=!gif-image
 </PRE>

 <HR>
 <H2><A NAME="logformat">LogFormat</A></H2>
 <!--%plaintext &lt;?INDEX {\tt LogFormat} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> LogFormat <EM>format</EM> [<EM>nickname</EM>]
 <BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> <CODE>LogFormat &quot;%h %l %u %t \&quot;%r\&quot;
 %s %b&quot;</CODE><BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<BR>
 <A
  HREF="directive-dict.html#Status"
  REL="Help"
 ><STRONG>Status:</STRONG></A> Base<BR>
 <A
  HREF="directive-dict.html#Compatibility"
  REL="Help"
 ><STRONG>Compatibility:</STRONG></A> Nickname only available in Apache 1.3
     or later
 <BR>
 <A
  HREF="directive-dict.html#Module"
  REL="Help"
 ><STRONG>Module:</STRONG></A> mod_log_config
 <P>
 This sets the format of the default logfile named by the
 <A
  HREF="#transferlog"
 ><SAMP>TransferLog</SAMP></A>
 directive .  See the section on
 <A HREF="#formats">Custom Log Formats</A> for details on the format
 arguments.
 </P>
 <P>
 If you include a nickname for the format on the directive line, you can
 use it in other <SAMP>LogFormat</SAMP> and
 <A HREF="#customlog"><SAMP>CustomLog</SAMP></A>
 directives rather than repeating the entire format string.
 </P>
 <P>
 A
 <SAMP>LogFormat</SAMP> directive which defines a nickname <STRONG>does
 nothing else</STRONG> -- that is, it <EM>only</EM> defines the nickname,
 it doesn't actually apply the format and make it the default.
 </P>

 <HR>

 <H2><A NAME="transferlog">TransferLog</A></H2>
 <!--%plaintext &lt;?INDEX {\tt TransferLog} directive&gt; -->
 <A
  HREF="directive-dict.html#Syntax"
  REL="Help"
 ><STRONG>Syntax:</STRONG></A> TransferLog <EM>file-pipe</EM><BR>
 <A
  HREF="directive-dict.html#Default"
  REL="Help"
 ><STRONG>Default:</STRONG></A> none<BR>
 <A
  HREF="directive-dict.html#Context"
  REL="Help"
 ><STRONG>Context:</STRONG></A> server config, virtual host<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_log_config<P>

 The TransferLog directive adds a log file in the format defined by the
 most recent
 <A
  HREF="#logformat"
 ><SAMP>LogFormat</SAMP></A>
 directive, or Common Log Format if no other default format has been
 specified.
 <EM>File-pipe</EM> is one
 of
 <DL><DT>A filename
 <DD>A filename relative to the <A HREF="core.html#serverroot">ServerRoot</A>.
 <DT> `|' followed by a command
 <DD>A program to receive the agent log information on its standard input.
 Note the a new program will not be started for a VirtualHost if it inherits
 the TransferLog from the main server.
 </DL>
 <STRONG>Security:</STRONG> if a program is used, then it will be
 run under the user who started httpd. This will be root if the server
 was started by root; be sure that the program is secure.<P>


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 </BODY>
 </HTML>
	<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
	<HTML>
	<HEAD>
	<TITLE>Apache module mod_log_config</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_log_config</H1>
	<P>
	This module is contained in the <CODE>mod_log_config.c</CODE> file,
	and is compiled in by default in Apache 1.2. mod_log_config replaces
	mod_log_common in Apache 1.2. Prior to version 1.2, mod_log_config was
	an optional module. It provides for logging of the requests made to
	the server, using the Common Log Format or a user-specified format.
	</P>

	<H2>Summary</H2>
	<P>
	Three directives are provided by this module: <CODE>TransferLog</CODE>
	to create a log file, <CODE>LogFormat</CODE> to set a custom format,
	and <CODE>CustomLog</CODE> to define a log file and format in one go.
	The <CODE>TransferLog</CODE> and <CODE>CustomLog</CODE> directives can
	be used multiple times in each server to cause each request to be
	logged to multiple files.
	</P>

	<H3>Compatibility notes</H3>

	<UL>
	<LI>This module is based on mod_log_config distributed with
	previous Apache releases, now updated to handle multiple logs.
	There is now no need to re-configure Apache to use configuration log
	formats.

	<LI>The module also implements the <CODE>CookieLog</CODE> directive,
	used to log user-tracking information created by <A
	HREF="mod_usertrack.html">mod_usertrack</A>. The use of
	<CODE>CookieLog</CODE> is deprecated, and a <CODE>CustomLog</CODE>
	should be defined to log user-tracking information instead.

	<LI>As of Apache 1.3.5, this module allows conditional logging
	based upon the setting of environment variables. That is,
	you can control whether a request should be logged or not
	based upon whether an arbitrary environment variable is
	defined or not. This is settable on a <EM>per</EM>-logfile
	basis.

	<LI>Beginning with Apache 1.3.5, the mod_log_config module has
	also subsumed the <CODE>RefererIgnore</CODE> functionality from
	<A HREF="mod_log_referer.html">mod_log_referer</A>. The effect
	of <CODE>RefererIgnore</CODE> can be achieved by combinations of
	<A HREF="mod_setenvif.html"><CODE>SetEnvIf</CODE></A> directives
	and conditional <CODE>CustomLog</CODE> definitions.

	</UL>

	<H2>Log File Formats</H2>

	Unless told otherwise with <TT>LogFormat</TT> the log files created by
	<TT>TransferLog</TT> will be in standard "Common Log Format"
	(CLF). The contents of each line in a CLF file are explained
	below. Alternatively, the log file can be customized (and if multiple
	log files are used, each can have a different format). Custom formats
	are set with <CODE>LogFormat</CODE> and <CODE>CustomLog</CODE>.

	<H3>Common Log Format</H3>

	The Common Log Format (CLF) file contains a separate line for each
	request. A line is composed of several tokens separated by spaces:

	<BLOCKQUOTE>
	host ident authuser date request status bytes
	</BLOCKQUOTE>
	If a token does not have a value then it is represented by a hyphen (-).
	The meanings and values of these tokens are as follows:
	<DL>
	<DT>host
	<DD>The fully-qualified domain name of the client, or its IP number if the
	name is not available.
	<DT>ident
	<DD>If <A HREF="core.html#identitycheck">IdentityCheck</A> is enabled and the
	client machine runs identd, then this is the identity information reported
	by the client.
	<DT>authuser
	<DD>If the request was for an password protected document, then this is
	the userid used in the request.
	<DT>date
	<DD>The date and time of the request, in the following format:
	<DL><DD><BLOCKQUOTE><CODE> date = [day/month/year:hour:minute:second zone] <BR>
	day = 2*digit<BR>
	month = 3*letter<BR>
	year = 4*digit<BR>
	hour = 2*digit<BR>
	minute = 2*digit<BR>
	second = 2*digit<BR>
	zone = (`+' \| `-') 4*digit</CODE></BLOCKQUOTE></DL>
	<DT>request
	<DD>The request line from the client, enclosed in double quotes
	(<CODE>"</CODE>).
	<DT>status
	<DD>The three digit status code returned to the client.
	<DT>bytes
	<DD>The number of bytes in the object returned to the client, not including
	any headers.
	</DL>

	<H3><A NAME="formats">Custom Log Formats</A></H3>

	The format argument to the <CODE>LogFormat</CODE> and
	<CODE>CustomLog</CODE> is a string. This string is logged to the log
	file for each request. It can contain literal characters copied into
	the log files, and `%' directives which are replaced in the log file
	by the values as follows:

	<PRE>
	%...a: Remote IP-address
	%...A: Local IP-address
	%...B: Bytes sent, excluding HTTP headers.
	%...b: Bytes sent, excluding HTTP headers. In CLF format
	i.e. a '-' rather than a 0 when no bytes are sent.
	%...{FOOBAR}e: The contents of the environment variable FOOBAR
	%...f: Filename
	%...h: Remote host
	%...H The request protocol
	%...{Foobar}i: The contents of Foobar: header line(s) in the request
	sent to the server.
	%...l: Remote logname (from identd, if supplied)
	%...m The request method
	%...{Foobar}n: The contents of note "Foobar" from another module.
	%...{Foobar}o: The contents of Foobar: header line(s) in the reply.
	%...p: The canonical Port of the server serving the request
	%...P: The process ID of the child that serviced the request.
	%...q The query string (prepended with a ? if a query string exists,
	otherwise an empty string)
	%...r: First line of request
	%...s: Status. For requests that got internally redirected, this is
	the status of the original request --- %...>s for the last.
	%...t: Time, in common log format time format (standard english format)
	%...{format}t: The time, in the form given by format, which should
	be in strftime(3) format. (potentially localised)
	%...T: The time taken to serve the request, in seconds.
	%...u: Remote user (from auth; may be bogus if return status (%s) is 401)
	%...U: The URL path requested.
	%...v: The canonical ServerName of the server serving the request.
	%...V: The server name according to the UseCanonicalName setting.
	</PRE>

	The `...' can be nothing at all (<EM>e.g.</EM>, <CODE>"%h %u %r %s %b"</CODE>), or it can
	indicate conditions for inclusion of the item (which will cause it
	to be replaced with `-' if the condition is not met). Note that
	there is no escaping performed on the strings from %r, %...i and
	%...o; some with long memories may remember that I thought this was
	a bad idea, once upon a time, and I'm still not comfortable with
	it, but it is difficult to see how to `do the right thing' with all
	of `%..i', unless we URL-escape everything and break with CLF.

	<P>

	The forms of condition are a list of HTTP status codes, which may
	or may not be preceded by `!'. Thus, `%400,501{User-agent}i' logs
	User-agent: on 400 errors and 501 errors (Bad Request, Not
	Implemented) only; `%!200,304,302{Referer}i' logs Referer: on all
	requests which did <STRONG>not</STRONG> return some sort of normal status.

	<P>

	Note that the common log format is defined by the string <CODE>"%h %l
	%u %t \"%r\" %s %b"</CODE>, which can be used as the basis for
	extending for format if desired (<EM>e.g.</EM>, to add extra fields at the end).
	NCSA's extended/combined log format would be <CODE>"%h %l %u %t \"%r\" %s %b \"%{Referer}i\" \"%{User-agent}i\""</CODE>.

	<P>

	Note that the canonical <A HREF="core.html#servername">ServerName</A>
	and <A HREF="core.html#port">Port</A> of the server serving the request
	are used for <CODE>%v</CODE> and <CODE>%p</CODE> respectively. This
	happens regardless of the
	<A HREF="core.html#usecanonicalname">UseCanonicalName</A> setting because
	otherwise log analysis programs would have to duplicate the entire
	vhost matching algorithm in order to decide what host really served
	the request.

	<H2>Using Multiple Log Files</H2>

	The <CODE>TransferLog</CODE> and <CODE>CustomLog</CODE> directives can
	be given more than once to log requests to multiple log files. Each
	request will be logged to all the log files defined by either of these
	directives.

	<H3>Use with Virtual Hosts</H3>

	If a <VirtualHost> section does not contain any
	<TT>TransferLog</TT> or <TT>CustomLog</TT> directives, the
	logs defined for the main server will be used. If it does
	contain one or more of these directives, requests serviced by
	this virtual host will only be logged in the log files defined
	within its definition, not in any of the main server's log files.
	See the examples below.
	<P>

	<H2>Security Considerations</H2>

	See the <A HREF="../misc/security_tips.html#security">security tips</A>
	document for details on why your security could be compromised if the
	directory where logfiles are stored is writable by anyone other than
	the user that starts the server.
	<P>
	<H2>Directives</H2>

	<UL>
	<LI><A HREF="#cookielog">CookieLog</A>
	<LI><A HREF="#customlog">CustomLog</A>
	<LI><A HREF="#customlog-conditional">CustomLog (conditional)</A>
	<LI><A HREF="#logformat">LogFormat</A>
	<LI><A HREF="#transferlog">TransferLog</A>
	</UL>
	<HR>


	<H2><A NAME="cookielog">CookieLog</A></H2>
	<!--%plaintext <?INDEX {\tt CookieLog} directive> -->
	<A
	HREF="directive-dict.html#Syntax"
	REL="Help"
	><STRONG>Syntax:</STRONG></A> CookieLog <EM>filename</EM><BR>
	<A
	HREF="directive-dict.html#Context"
	REL="Help"
	><STRONG>Context:</STRONG></A> server config, virtual host<BR>
	<A
	HREF="directive-dict.html#Module"
	REL="Help"
	><STRONG>Module:</STRONG></A> mod_cookies<BR>
	<A
	HREF="directive-dict.html#Compatibility"
	REL="Help"
	><STRONG>Compatibility:</STRONG></A> Only available in Apache 1.2 and above<P>

	The CookieLog directive sets the filename for logging of cookies.
	The filename is relative to the <A
	HREF="core.html#serverroot">ServerRoot</A>. This directive is included
	only for compatibility with
	<A HREF="mod_cookies.html">mod_cookies</A>, and is deprecated.
	<P>

	<HR>
	<H2><A NAME="customlog">CustomLog</A></H2>
	<A
	HREF="directive-dict.html#Syntax"
	REL="Help"
	><STRONG>Syntax:</STRONG></A> CustomLog <EM>file-pipe</EM>
	<EM>format-or-nickname</EM><BR>
	<A
	HREF="directive-dict.html#Context"
	REL="Help"
	><STRONG>Context:</STRONG></A> server config, virtual host<BR>
	<A
	HREF="directive-dict.html#Status"
	REL="Help"
	><STRONG>Status:</STRONG></A> Base<BR>
	<A
	HREF="directive-dict.html#Compatibility"
	REL="Help"
	><STRONG>Compatibility:</STRONG></A> Nickname only available in Apache 1.3
	or later
	<BR>
	<A
	HREF="directive-dict.html#Module"
	REL="Help"
	><STRONG>Module:</STRONG></A> mod_log_config
	<P>
	The first argument is the filename to which log records should be
	written. This is used
	exactly like the argument to
	<A
	HREF="#transferlog"
	><SAMP>TransferLog</SAMP></A>;
	that is, it is either a full path or relative to the current
	server root.
	</P>
	<P>
	The format argument specifies a format for each line of the log file.
	The options available for the format are exactly the same as for
	the argument of the <TT>LogFormat</TT> directive. If the format
	includes any spaces (which it will do in almost all cases) it
	should be enclosed in double quotes.
	</P>
	<P>
	Instead of an actual format string, you can use a format nickname defined with
	the
	<A
	HREF="#logformat"
	><SAMP>LogFormat</SAMP></A>
	directive.
	</P>

	<HR>
	<H2><A NAME="customlog-conditional">CustomLog (conditional)</A></H2>
	<A
	HREF="directive-dict.html#Syntax"
	REL="Help"
	><STRONG>Syntax:</STRONG></A> CustomLog <EM>file-pipe</EM>
	<EM>format-or-nickname</EM>
	env=[!]<EM>environment-variable</EM><BR>
	<A
	HREF="directive-dict.html#Context"
	REL="Help"
	><STRONG>Context:</STRONG></A> server config, virtual host<BR>
	<A
	HREF="directive-dict.html#Status"
	REL="Help"
	><STRONG>Status:</STRONG></A> Base<BR>
	<A
	HREF="directive-dict.html#Compatibility"
	REL="Help"
	><STRONG>Compatibility:</STRONG></A> Only available in Apache 1.3.5
	or later
	<BR>
	<A
	HREF="directive-dict.html#Module"
	REL="Help"
	><STRONG>Module:</STRONG></A> mod_log_config
	<P>

	The behaviour of this form of the <SAMP>CustomLog</SAMP> directive is almost
	identical to the <A HREF="#customlog">standard <CODE>CustomLog</CODE></A>
	directive. The difference is that the '<CODE>env=</CODE>' clause controls
	whether a particular request will be logged in the specified file or
	not. If the specified environment variable is set for the
	request (or is not set, in the case of a '<CODE>env=!<EM>name</EM></CODE>'
	clause), then the request will be logged.
	</P>
	<P>
	Environment variables can be set on a <EM>per</EM>-request basis
	using the <A HREF="mod_setenvif.html">mod_setenvif</A> and/or
	<A HREF="mod_rewrite.html">mod_rewrite</A> modules. For example,
	if you don't want to record requests for all GIF images on
	your server in a separate logfile but not your main log, you
	can use:
	</P>
	<PRE>
	SetEnvIf Request_URI \.gif$ gif-image
	CustomLog gif-requests.log common env=gif-image
	CustomLog nongif-requests.log common env=!gif-image
	</PRE>

	<HR>
	<H2><A NAME="logformat">LogFormat</A></H2>
	<!--%plaintext <?INDEX {\tt LogFormat} directive> -->
	<A
	HREF="directive-dict.html#Syntax"
	REL="Help"
	><STRONG>Syntax:</STRONG></A> LogFormat <EM>format</EM> [<EM>nickname</EM>]
	<BR>
	<A
	HREF="directive-dict.html#Default"
	REL="Help"
	><STRONG>Default:</STRONG></A> <CODE>LogFormat "%h %l %u %t \"%r\"
	%s %b"</CODE><BR>
	<A
	HREF="directive-dict.html#Context"
	REL="Help"
	><STRONG>Context:</STRONG></A> server config, virtual host<BR>
	<A
	HREF="directive-dict.html#Status"
	REL="Help"
	><STRONG>Status:</STRONG></A> Base<BR>
	<A
	HREF="directive-dict.html#Compatibility"
	REL="Help"
	><STRONG>Compatibility:</STRONG></A> Nickname only available in Apache 1.3
	or later
	<BR>
	<A
	HREF="directive-dict.html#Module"
	REL="Help"
	><STRONG>Module:</STRONG></A> mod_log_config
	<P>
	This sets the format of the default logfile named by the
	<A
	HREF="#transferlog"
	><SAMP>TransferLog</SAMP></A>
	directive . See the section on
	<A HREF="#formats">Custom Log Formats</A> for details on the format
	arguments.
	</P>
	<P>
	If you include a nickname for the format on the directive line, you can
	use it in other <SAMP>LogFormat</SAMP> and
	<A HREF="#customlog"><SAMP>CustomLog</SAMP></A>
	directives rather than repeating the entire format string.
	</P>
	<P>
	A
	<SAMP>LogFormat</SAMP> directive which defines a nickname <STRONG>does
	nothing else</STRONG> -- that is, it <EM>only</EM> defines the nickname,
	it doesn't actually apply the format and make it the default.
	</P>

	<HR>

	<H2><A NAME="transferlog">TransferLog</A></H2>
	<!--%plaintext <?INDEX {\tt TransferLog} directive> -->
	<A
	HREF="directive-dict.html#Syntax"
	REL="Help"
	><STRONG>Syntax:</STRONG></A> TransferLog <EM>file-pipe</EM><BR>
	<A
	HREF="directive-dict.html#Default"
	REL="Help"
	><STRONG>Default:</STRONG></A> none<BR>
	<A
	HREF="directive-dict.html#Context"
	REL="Help"
	><STRONG>Context:</STRONG></A> server config, virtual host<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_log_config<P>

	The TransferLog directive adds a log file in the format defined by the
	most recent
	<A
	HREF="#logformat"
	><SAMP>LogFormat</SAMP></A>
	directive, or Common Log Format if no other default format has been
	specified.
	<EM>File-pipe</EM> is one
	of
	<DL><DT>A filename
	<DD>A filename relative to the <A HREF="core.html#serverroot">ServerRoot</A>.
	<DT> `\|' followed by a command
	<DD>A program to receive the agent log information on its standard input.
	Note the a new program will not be started for a VirtualHost if it inherits
	the TransferLog from the main server.
	</DL>
	<STRONG>Security:</STRONG> if a program is used, then it will be
	run under the user who started httpd. This will be root if the server
	was started by root; be sure that the program is secure.<P>


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