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 <H1>Module mod_log_config</h1>

 This module is contained in the <code>mod_log_config.c</code> file, and is not
 compiled in by default. It provides for logging of the requests made to
 the server, using a user-specified format.

 <h2>Summary</h2>
 This is an EXPERIMENTAL module, which implements the TransferLog directive
 (same as the common log module), and an additional directive, LogFormat.
 Bugs would not surprise me.<P>

 The argument to the <A HREF="#logformat">LogFormat</A> is a string, which can
 include literal characters copied into the log files, and `%' directives as
 follows:

 <PRE>
 %...h:          Remote host
 %...l:          Remote logname (from identd, if supplied)
 %...u:          Remote user (from auth; may be bogus if return
                 status (%s) is 401)
 %...t:          Time, in common log format time format
 %...r:          First line of request
 %...s:          Status.  For requests that got internally redirected,
                 this is status of the <b>original</b> request --- %...>s
                 for the last.
 %...b:          Bytes sent.
 %...{Foobar}i:  The contents of Foobar: header line(s) in the request
                 sent to the client.
 %...{Foobar}o:  The contents of Foobar: header line(s) in the reply.
 </PRE>

 The `...' can be nothing at all (e.g. <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 <b>not</b> return some sort of normal status.

 <P>

 The default LogFormat reproduces CLF; see below.

 <P>

 The way this is supposed to work with virtual hosts is as follows:
 a virtual host can have its own LogFormat, or its own TransferLog.
 If it doesn't have its own LogFormat, it inherits from the main
 server.  If it doesn't have its own TransferLog, it writes to the
 same descriptor (meaning the same process for `| ...').

 <P>

 That means that you can do things like:

 <blockquote><code>
 &lt;VirtualHost hosta.com&gt;<br>
 LogFormat "hosta ..."<br>
 ...<br>
 &lt;/VirtualHost&gt;<br>
 <br>
 &lt;VirtualHost hosta.com&gt;<br>
 LogFormat "hostb ..."<br>
 ...<br>
 &lt;/VirtualHost&gt;</code></blockquote>

 ... to have different virtual servers write into the same log file,
 but have some indication which host they came from, though a %v
 directive may well be a better way to handle this.  Look for more
 changes to come to this format.<p>


 <!--%hypertext -->

 <h2>Directives</h2>

 <ul>
 <li><A HREF="#logformat">LogFormat</A>
 <li><A HREF="#transferlog">TransferLog</A>
 </ul>
 <hr>
 <!--/%hypertext -->

 <A name="logformat"><h2>LogFormat</h2></A>
 <!--%plaintext &lt;?INDEX {\tt LogFormat} directive&gt; -->
 <strong>Syntax:</strong> LogFormat <em>string</em><br>
 <strong>Default:</strong> <code>LogFormat &quot;%h %l %u %t \&quot;%r\&quot;
 %s %b&quot;</code><br>
 <Strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Experimental<br>
 <strong>Module:</strong> mod_log_config<p>

 This sets the format of the logfile.<p><hr>


 <A name="transferlog"><h2>TransferLog</h2></A>
 <!--%plaintext &lt;?INDEX {\tt TransferLog} directive&gt; -->
 <strong>Syntax:</strong> TransferLog <em>file-pipe</em><br>
 <strong>Default:</strong> <code>TransferLog logs/transfer_log</code><br>
 <Strong>Context:</strong> server config, virtual host<br>
 <strong>Status:</strong> Experimental<br>
 <strong>Module:</strong> mod_log_config<p>

 The TransferLog directive sets the name of the file to which the server will
 log the incoming requests. <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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	<H1>Module mod_log_config</h1>

	This module is contained in the <code>mod_log_config.c</code> file, and is not
	compiled in by default. It provides for logging of the requests made to
	the server, using a user-specified format.

	<h2>Summary</h2>
	This is an EXPERIMENTAL module, which implements the TransferLog directive
	(same as the common log module), and an additional directive, LogFormat.
	Bugs would not surprise me.<P>

	The argument to the <A HREF="#logformat">LogFormat</A> is a string, which can
	include literal characters copied into the log files, and `%' directives as
	follows:

	<PRE>
	%...h: Remote host
	%...l: Remote logname (from identd, if supplied)
	%...u: Remote user (from auth; may be bogus if return
	status (%s) is 401)
	%...t: Time, in common log format time format
	%...r: First line of request
	%...s: Status. For requests that got internally redirected,
	this is status of the <b>original</b> request --- %...>s
	for the last.
	%...b: Bytes sent.
	%...{Foobar}i: The contents of Foobar: header line(s) in the request
	sent to the client.
	%...{Foobar}o: The contents of Foobar: header line(s) in the reply.
	</PRE>

	The `...' can be nothing at all (e.g. <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 <b>not</b> return some sort of normal status.

	<P>

	The default LogFormat reproduces CLF; see below.

	<P>

	The way this is supposed to work with virtual hosts is as follows:
	a virtual host can have its own LogFormat, or its own TransferLog.
	If it doesn't have its own LogFormat, it inherits from the main
	server. If it doesn't have its own TransferLog, it writes to the
	same descriptor (meaning the same process for `\| ...').

	<P>

	That means that you can do things like:

	<blockquote><code>
	<VirtualHost hosta.com><br>
	LogFormat "hosta ..."<br>
	...<br>
	</VirtualHost><br>
	<br>
	<VirtualHost hosta.com><br>
	LogFormat "hostb ..."<br>
	...<br>
	</VirtualHost></code></blockquote>

	... to have different virtual servers write into the same log file,
	but have some indication which host they came from, though a %v
	directive may well be a better way to handle this. Look for more
	changes to come to this format.<p>


	<!--%hypertext -->

	<h2>Directives</h2>

	<ul>
	<li><A HREF="#logformat">LogFormat</A>
	<li><A HREF="#transferlog">TransferLog</A>
	</ul>
	<hr>
	<!--/%hypertext -->

	<A name="logformat"><h2>LogFormat</h2></A>
	<!--%plaintext <?INDEX {\tt LogFormat} directive> -->
	<strong>Syntax:</strong> LogFormat <em>string</em><br>
	<strong>Default:</strong> <code>LogFormat "%h %l %u %t \"%r\"
	%s %b"</code><br>
	<Strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Experimental<br>
	<strong>Module:</strong> mod_log_config<p>

	This sets the format of the logfile.<p><hr>


	<A name="transferlog"><h2>TransferLog</h2></A>
	<!--%plaintext <?INDEX {\tt TransferLog} directive> -->
	<strong>Syntax:</strong> TransferLog <em>file-pipe</em><br>
	<strong>Default:</strong> <code>TransferLog logs/transfer_log</code><br>
	<Strong>Context:</strong> server config, virtual host<br>
	<strong>Status:</strong> Experimental<br>
	<strong>Module:</strong> mod_log_config<p>

	The TransferLog directive sets the name of the file to which the server will
	log the incoming requests. <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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