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@@ -1,405 +1,454 @@
-<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
-<html>
-<head>
-<title>Apache Tutorial: Dynamic Content with CGI</title>
-<link rev="made" href="mailto:[EMAIL PROTECTED]">
-</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">Dynamic Content with CGI</h1>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
+ "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd";>
-<a name="__index__"></a> <!-- INDEX BEGIN -->
-
+<html xmlns="http://www.w3.org/1999/xhtml";>
+ <head>
+ <meta name="generator" content="HTML Tidy, see www.w3.org" />
+
+ <title>Apache Tutorial: Dynamic Content with CGI</title>
+ <link rev="made" href="mailto:[EMAIL PROTECTED]" />
+ </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">Dynamic Content with CGI</h1>
+ <a id="__index__" name="__index__"></a> <!-- INDEX BEGIN -->
+
+
+ <ul>
+ <li><a href="#dynamiccontentwithcgi">Dynamic Content with
+ CGI</a></li>
+
+ <li>
+ <a href="#configuringapachetopermitcgi">Configuring Apache
+ to permit CGI</a>
+
+ <ul>
+ <li><a href="#scriptalias">ScriptAlias</a></li>
+
+ <li>
+ <a href="#cgioutsideofscriptaliasdirectories">CGI
+ outside of ScriptAlias directories</a>
+
+ <ul>
+ <li><a
+ href="#explicitlyusingoptionstopermitcgiexecution">Explicitly
+ using Options to permit CGI execution</a></li>
+
+ <li><a href="#htaccessfiles">.htaccess files</a></li>
+ </ul>
+ </li>
+ </ul>
+ </li>
+
+ <li>
+ <a href="#writingacgiprogram">Writing a CGI program</a>
+
+ <ul>
+ <li><a href="#yourfirstcgiprogram">Your first CGI
+ program</a></li>
+ </ul>
+ </li>
+
+ <li>
+ <a href="#butitsstillnotworking">But it's still not
+ working!</a>
+
+ <ul>
+ <li><a href="#filepermissions">File permissions</a></li>
+
+ <li><a href="#pathinformation">Path information</a></li>
+
+ <li><a href="#syntaxerrors">Syntax errors</a></li>
+
+ <li><a href="#errorlogs">Error logs</a></li>
+ </ul>
+ </li>
+
+ <li>
+ <a href="#whatsgoingonbehindthescenes">What's going on
+ behind the scenes?</a>
+
+ <ul>
+ <li><a href="#environmentvariables">Environment
+ variables</a></li>
+
+ <li><a href="#stdinandstdout">STDIN and STDOUT</a></li>
+ </ul>
+ </li>
+
+ <li><a href="#cgimoduleslibraries">CGI
+ modules/libraries</a></li>
+
+ <li><a href="#formoreinformation">For more
+ information</a></li>
+ </ul>
+ <!-- INDEX END -->
+ <hr />
+
+ <h2><a id="dynamiccontentwithcgi"
+ name="dynamiccontentwithcgi">Dynamic Content with CGI</a></h2>
+
+ <table border="1">
+ <tr>
+ <td valign="top"><strong>Related Modules</strong><br />
+ <br />
+ <a href="../mod/mod_alias.html">mod_alias</a><br />
+ <a href="../mod/mod_cgi.html">mod_cgi</a><br />
+ </td>
+
+ <td valign="top"><strong>Related Directives</strong><br />
+ <br />
+ <a
+ href="../mod/mod_mime.html#addhandler">AddHandler</a><br />
+ <a href="../mod/core.html#options">Options</a><br />
+ <a
+ href="../mod/mod_alias.html#scriptalias">ScriptAlias</a><br />
+ </td>
+ </tr>
+ </table>
+
+ <p>The CGI (Common Gateway Interface) defines a way for a web
+ server to interact with external content-generating programs,
+ which are often referred to as CGI programs or CGI scripts. It
+ is the simplest, and most common, way to put dynamic content on
+ your web site. This document will be an introduction to setting
+ up CGI on your Apache web server, and getting started writing
+ CGI programs.</p>
+ <hr />
+
+ <h2><a id="configuringapachetopermitcgi"
+ name="configuringapachetopermitcgi">Configuring Apache to
+ permit CGI</a></h2>
+
+ <p>In order to get your CGI programs to work properly, you'll
+ need to have Apache configured to permit CGI execution. There
+ are several ways to do this.</p>
+
+ <h3><a id="scriptalias" name="scriptalias">ScriptAlias</a></h3>
+
+ <p>The <code>ScriptAlias</code> directive tells Apache that a
+ particular directory is set aside for CGI programs. Apache will
+ assume that every file in this directory is a CGI program, and
+ will attempt to execute it, when that particular resource is
+ requested by a client.</p>
-<ul>
-<li><a href="#dynamiccontentwithcgi">Dynamic Content with
-CGI</a></li>
-
-<li><a href="#configuringapachetopermitcgi">Configuring Apache to
-permit CGI</a>
-
-<ul>
-<li><a href="#scriptalias">ScriptAlias</a></li>
-
-<li><a href="#cgioutsideofscriptaliasdirectories">CGI outside of
-ScriptAlias directories</a>
-
-<ul>
-<li><a href="#explicitlyusingoptionstopermitcgiexecution">Explicitly using
-Options to permit CGI execution</a></li>
-
-<li><a href="#htaccessfiles">.htaccess files</a></li>
-</ul>
-</li>
-</ul>
-</li>
-
-<li><a href="#writingacgiprogram">Writing a CGI program</a>
-
-<ul>
-<li><a href="#yourfirstcgiprogram">Your first CGI program</a></li>
-</ul>
-</li>
-
-<li><a href="#butitsstillnotworking">But it's still not
-working!</a>
-
-<ul>
-<li><a href="#filepermissions">File permissions</a></li>
-
-<li><a href="#pathinformation">Path information</a></li>
-
-<li><a href="#syntaxerrors">Syntax errors</a></li>
-
-<li><a href="#errorlogs">Error logs</a></li>
-</ul>
-</li>
-
-<li><a href="#whatsgoingonbehindthescenes">What's going on behind
-the scenes?</a>
-
-<ul>
-<li><a href="#environmentvariables">Environment variables</a></li>
-
-<li><a href="#stdinandstdout">STDIN and STDOUT</a></li>
-</ul>
-</li>
-
-<li><a href="#cgimoduleslibraries">CGI modules/libraries</a></li>
-
-<li><a href="#formoreinformation">For more information</a></li>
-</ul>
-
-<!-- INDEX END -->
-<hr>
-<h2><a name="dynamiccontentwithcgi">Dynamic Content with
-CGI</a></h2>
-
-<table border="1">
-<tr><td valign="top">
-<strong>Related Modules</strong><br><br>
-
-<a href="../mod/mod_alias.html">mod_alias</a><br>
-<a href="../mod/mod_cgi.html">mod_cgi</a><br>
-
-</td><td valign="top">
-<strong>Related Directives</strong><br><br>
-
-<a href="../mod/mod_mime.html#addhandler">AddHandler</a><br>
-<A HREF="../mod/core.html#options">Options</a><br>
-<a href="../mod/mod_alias.html#scriptalias">ScriptAlias</a><br>
-
-</td></tr></table>
-
-<p>The CGI (Common Gateway Interface) defines a way for a web server
-to interact with external content-generating programs, which are often
-referred to as CGI programs or CGI scripts. It is the simplest, and
-most common, way to put dynamic content on your web site. This
-document will be an introduction to setting up CGI on your Apache web
-server, and getting started writing CGI programs.</p>
-
-<hr>
-<h2><a name="configuringapachetopermitcgi">Configuring Apache to
-permit CGI</a></h2>
-
-<p>In order to get your CGI programs to work properly, you'll need to
-have Apache configured to permit CGI execution. There are several ways
-to do this.</p>
-
-<h3><a name="scriptalias">ScriptAlias</a></h3>
-
-<p>The <code>ScriptAlias</code> directive tells Apache that a
-particular directory is set aside for CGI programs. Apache will assume
-that every file in this directory is a CGI program, and will attempt to
-execute it, when that particular resource is requested by a client.</p>
-
-<p>The <code>ScriptAlias</code> directive looks like:</p>
-
+ <p>The <code>ScriptAlias</code> directive looks like:</p>
<pre>
ScriptAlias /cgi-bin/ /usr/local/apache/cgi-bin/
</pre>
-
-<p>The example shown is from your default <code>httpd.conf</code>
-configuration file, if you installed Apache in the default location.
-The <code>ScriptAlias</code> directive is much like the
-<code>Alias</code> directive, which defines a URL prefix that is to
-mapped to a particular directory. <code>Alias</code> and
-<code>ScriptAlias</code> are usually used for directories that are
-outside of the <code>DocumentRoot</code> directory. The difference
-between <code>Alias</code> and <code>ScriptAlias</code> is that
-<code>ScriptAlias</code> has the added meaning that everything under
-that URL prefix will be considered a CGI program. So, the example above
-tells Apache that any request for a resource beginning with
-<code>/cgi-bin/</code> should be served from the directory
-<code>/usr/local/apache/cgi-bin/</code>, and should be treated as a CGI
-program.</p>
-
-<p>For example, if the URL
-<code>http://dev.rcbowen.com/cgi-bin/test.pl</code> is requested,
-Apache will attempt to execute the file
-<code>/usr/local/apache/cgi-bin/test.pl</code> and return the output.
-Of course, the file will have to exist, and be executable, and return
-output in a particular way, or Apache will return an error message.</p>
-
-<h3><a name="cgioutsideofscriptaliasdirectories">CGI outside of
-ScriptAlias directories</a></h3>
-
-<p>CGI programs are often restricted to <code>ScriptAlias</code>'ed
-directories for security reasons. In this way, administrators can
-tightly control who is allowed to use CGI programs. However, if the
-proper security precautions are taken, there is no reason why
-CGI programs cannot be run from arbitrary directories. For example,
-you may wish to let users have web content in their home directories
-with the <code>UserDir</code> directive. If they want to have their
-own CGI programs, but don't have access to the main
-<code>cgi-bin</code> directory, they will need to be able to run CGI
-programs elsewhere.</p>
-
-<h3><a name="explicitlyusingoptionstopermitcgiexecution">Explicitly using
-Options to permit CGI execution</a></h3>
-
-<p>You could explicitly use the <code>Options</code> directive, inside
-your main server configuration file, to specify that CGI execution was
-permitted in a particular directory:</p>
+ <p>The example shown is from your default
+ <code>httpd.conf</code> configuration file, if you installed
+ Apache in the default location. The <code>ScriptAlias</code>
+ directive is much like the <code>Alias</code> directive, which
+ defines a URL prefix that is to mapped to a particular
+ directory. <code>Alias</code> and <code>ScriptAlias</code> are
+ usually used for directories that are outside of the
+ <code>DocumentRoot</code> directory. The difference between
+ <code>Alias</code> and <code>ScriptAlias</code> is that
+ <code>ScriptAlias</code> has the added meaning that everything
+ under that URL prefix will be considered a CGI program. So, the
+ example above tells Apache that any request for a resource
+ beginning with <code>/cgi-bin/</code> should be served from the
+ directory <code>/usr/local/apache/cgi-bin/</code>, and should
+ be treated as a CGI program.</p>
+
+ <p>For example, if the URL
+ <code>http://dev.rcbowen.com/cgi-bin/test.pl</code> is
+ requested, Apache will attempt to execute the file
+ <code>/usr/local/apache/cgi-bin/test.pl</code> and return the
+ output. Of course, the file will have to exist, and be
+ executable, and return output in a particular way, or Apache
+ will return an error message.</p>
+
+ <h3><a id="cgioutsideofscriptaliasdirectories"
+ name="cgioutsideofscriptaliasdirectories">CGI outside of
+ ScriptAlias directories</a></h3>
+
+ <p>CGI programs are often restricted to
+ <code>ScriptAlias</code>'ed directories for security reasons.
+ In this way, administrators can tightly control who is allowed
+ to use CGI programs. However, if the proper security
+ precautions are taken, there is no reason why CGI programs
+ cannot be run from arbitrary directories. For example, you may
+ wish to let users have web content in their home directories
+ with the <code>UserDir</code> directive. If they want to have
+ their own CGI programs, but don't have access to the main
+ <code>cgi-bin</code> directory, they will need to be able to
+ run CGI programs elsewhere.</p>
+
+ <h3><a id="explicitlyusingoptionstopermitcgiexecution"
+ name="explicitlyusingoptionstopermitcgiexecution">Explicitly
+ using Options to permit CGI execution</a></h3>
+
+ <p>You could explicitly use the <code>Options</code> directive,
+ inside your main server configuration file, to specify that CGI
+ execution was permitted in a particular directory:</p>
<pre>
<Directory /usr/local/apache/htdocs/somedir>
Options +ExecCGI
</Directory>
</pre>
-
-<p>The above directive tells Apache to permit the execution of CGI
-files. You will also need to tell the server what files are CGI files.
-The following <code>AddHandler</code> directive tells the server
-to treat all files with the <code>cgi</code> or <code>pl</code>
-extension as CGI programs:</p>
+ <p>The above directive tells Apache to permit the execution of
+ CGI files. You will also need to tell the server what files are
+ CGI files. The following <code>AddHandler</code> directive
+ tells the server to treat all files with the <code>cgi</code>
+ or <code>pl</code> extension as CGI programs:</p>
<pre>
AddHandler cgi-script cgi pl
</pre>
-<h3><a name="htaccessfiles">.htaccess files</a></h3>
+ <h3><a id="htaccessfiles" name="htaccessfiles">.htaccess
+ files</a></h3>
-<p>A <code>.htaccess</code> file is a way to set configuration
-directives on a per-directory basis. When Apache serves a resource, it
-looks in the directory from which it is serving a file for a file
-called <code>.htaccess</code>, and, if it finds it, it will apply
-directives found therein. <code>.htaccess</code> files can be permitted
-with the <code>AllowOverride</code> directive, which specifies what
-types of directives can appear in these files, or if they are not
-allowed at all. To permit the directive we will need for this purpose,
-the following configuration will be needed in your main server
-configuration:</p>
-
+ <p>A <code>.htaccess</code> file is a way to set configuration
+ directives on a per-directory basis. When Apache serves a
+ resource, it looks in the directory from which it is serving a
+ file for a file called <code>.htaccess</code>, and, if it finds
+ it, it will apply directives found therein.
+ <code>.htaccess</code> files can be permitted with the
+ <code>AllowOverride</code> directive, which specifies what
+ types of directives can appear in these files, or if they are
+ not allowed at all. To permit the directive we will need for
+ this purpose, the following configuration will be needed in
+ your main server configuration:</p>
<pre>
AllowOverride Options
</pre>
-
-<p>In the <code>.htaccess</code> file, you'll need the following
-directive:</p>
+ <p>In the <code>.htaccess</code> file, you'll need the
+ following directive:</p>
<pre>
Options +ExecCGI
</pre>
-
-<p>which tells Apache that execution of CGI programs is permitted in
-this directory.</p>
-<hr>
-<h2><a name="writingacgiprogram">Writing a CGI program</a></h2>
-
-<p>There are two main differences between ``regular'' programming, and
-CGI programming.</p>
-
-<p>First, all output from your CGI program must be preceded by a
-MIME-type header. This is HTTP header that tells the client what sort
-of content it is receiving. Most of the time, this will look like:</p>
-
+ <p>which tells Apache that execution of CGI programs is
+ permitted in this directory.</p>
+ <hr />
+
+ <h2><a id="writingacgiprogram"
+ name="writingacgiprogram">Writing a CGI program</a></h2>
+
+ <p>There are two main differences between ``regular''
+ programming, and CGI programming.</p>
+
+ <p>First, all output from your CGI program must be preceded by
+ a MIME-type header. This is HTTP header that tells the client
+ what sort of content it is receiving. Most of the time, this
+ will look like:</p>
<pre>
Content-type: text/html
</pre>
-<p>Secondly, your output needs to be in HTML, or some other format that
-a browser will be able to display. Most of the time, this will be HTML,
-but occasionally you might write a CGI program that outputs a gif
-image, or other non-HTML content.</p>
-
-<p>Apart from those two things, writing a CGI program will look a lot
-like any other program that you might write.</p>
-
-<h3><a name="yourfirstcgiprogram">Your first CGI program</a></h3>
-
-<p>The following is an example CGI program that prints one line to your
-browser. Type in the following, save it to a file called
-<code>first.pl</code>, and put it in your <code>cgi-bin</code>
-directory.</p>
-
+ <p>Secondly, your output needs to be in HTML, or some other
+ format that a browser will be able to display. Most of the
+ time, this will be HTML, but occasionally you might write a CGI
+ program that outputs a gif image, or other non-HTML
+ content.</p>
+
+ <p>Apart from those two things, writing a CGI program will look
+ a lot like any other program that you might write.</p>
+
+ <h3><a id="yourfirstcgiprogram" name="yourfirstcgiprogram">Your
+ first CGI program</a></h3>
+
+ <p>The following is an example CGI program that prints one line
+ to your browser. Type in the following, save it to a file
+ called <code>first.pl</code>, and put it in your
+ <code>cgi-bin</code> directory.</p>
<pre>
#!/usr/bin/perl
print "Content-type: text/html\r\n\r\n";
print "Hello, World.";
</pre>
-
-<p>Even if you are not familiar with Perl, you should be able to see
-what is happening here. The first line tells Apache (or whatever shell
-you happen to be running under) that this program can be executed by
-feeding the file to the interpreter found at the location
-<code>/usr/bin/perl</code>. The second line prints the content-type
-declaration we talked about, followed by two carriage-return newline
-pairs. This puts a blank line after the header, to indicate the end of
-the HTTP headers, and the beginning of the body. The third line prints
-the string ``Hello, World.'' And that's the end of it.</p>
-<p>If you open your favorite browser and tell it to get the address</p>
+ <p>Even if you are not familiar with Perl, you should be able
+ to see what is happening here. The first line tells Apache (or
+ whatever shell you happen to be running under) that this
+ program can be executed by feeding the file to the interpreter
+ found at the location <code>/usr/bin/perl</code>. The second
+ line prints the content-type declaration we talked about,
+ followed by two carriage-return newline pairs. This puts a
+ blank line after the header, to indicate the end of the HTTP
+ headers, and the beginning of the body. The third line prints
+ the string ``Hello, World.'' And that's the end of it.</p>
+ <p>If you open your favorite browser and tell it to get the
+ address</p>
<pre>
http://www.example.com/cgi-bin/first.pl
</pre>
-
-<p>or wherever you put your file, you will see the one line
-<code>Hello, World.</code> appear in your browser window. It's not very
-exciting, but once you get that working, you'll have a good chance of
-getting just about anything working.</p>
-
-<hr>
-<h2><a name="butitsstillnotworking">But it's still not
-working!</a></h2>
-
-<p>There are four basic things that you may see in your browser when
-you try to access your CGI program from the web:</p>
-
-<dl>
-<dt>The output of your CGI program</dt>
-<dd>Great! That means everything worked fine.<br><br></dd>
-
-<dt>The source code of your CGI program or a "POST Method Not Allowed"
-message</dt>
-<dd>That means that you have not properly configured
-Apache to process your CGI program. Reread the section on <a
-href="#configuringapachetopermitcgi">configuring Apache</a> and try to
-find what you missed.<br><br></dd>
-
-<dt>A message starting with "Forbidden"</dt> <dd>That means that there
-is a permissions problem. Check the <a href="#errorlogs">Apache
-error log</a> and the section below on <a
-href="#filepermissions">file permissions</a>.<br><br></dd>
-
-<dt>A message saying "Internal Server Error"</dt> <dd>If you check the
-<a href="#errorlogs">Apache error log</a>, you will probably find
-that it says "Premature end of script headers", possibly along with an
-error message generated by your CGI program. In this case, you will
-want to check each of the below sections to see what might be preventing
-your CGI program from emitting the proper HTTP headers.</dd>
-</dl>
-
-
-<h3><a name="filepermissions">File permissions</a></h3>
-
-<p>Remember that the server does not run as you. That is, when the
-server starts up, it is running with the permissions of an unprivileged
-user - usually ``nobody'', or ``www'' - and so it will need extra
-permissions to execute files that are owned by you. Usually, the way to
-give a file sufficient permissions to be executed by ``nobody'' is to
-give everyone execute permission on the file:</p>
+ <p>or wherever you put your file, you will see the one line
+ <code>Hello, World.</code> appear in your browser window. It's
+ not very exciting, but once you get that working, you'll have a
+ good chance of getting just about anything working.</p>
+ <hr />
+
+ <h2><a id="butitsstillnotworking"
+ name="butitsstillnotworking">But it's still not
+ working!</a></h2>
+
+ <p>There are four basic things that you may see in your browser
+ when you try to access your CGI program from the web:</p>
+
+ <dl>
+ <dt>The output of your CGI program</dt>
+
+ <dd>Great! That means everything worked fine.<br />
+ <br />
+ </dd>
+
+ <dt>The source code of your CGI program or a "POST Method Not
+ Allowed" message</dt>
+
+ <dd>That means that you have not properly configured Apache
+ to process your CGI program. Reread the section on <a
+ href="#configuringapachetopermitcgi">configuring Apache</a>
+ and try to find what you missed.<br />
+ <br />
+ </dd>
+
+ <dt>A message starting with "Forbidden"</dt>
+
+ <dd>That means that there is a permissions problem. Check the
+ <a href="#errorlogs">Apache error log</a> and the section
+ below on <a href="#filepermissions">file
+ permissions</a>.<br />
+ <br />
+ </dd>
+
+ <dt>A message saying "Internal Server Error"</dt>
+
+ <dd>If you check the <a href="#errorlogs">Apache error
+ log</a>, you will probably find that it says "Premature end
+ of script headers", possibly along with an error message
+ generated by your CGI program. In this case, you will want to
+ check each of the below sections to see what might be
+ preventing your CGI program from emitting the proper HTTP
+ headers.</dd>
+ </dl>
+
+ <h3><a id="filepermissions" name="filepermissions">File
+ permissions</a></h3>
+
+ <p>Remember that the server does not run as you. That is, when
+ the server starts up, it is running with the permissions of an
+ unprivileged user - usually ``nobody'', or ``www'' - and so it
+ will need extra permissions to execute files that are owned by
+ you. Usually, the way to give a file sufficient permissions to
+ be executed by ``nobody'' is to give everyone execute
+ permission on the file:</p>
<pre>
chmod a+x first.pl
</pre>
-<p>Also, if your program reads from, or writes to, any other files,
-those files will need to have the correct permissions to permit
-this.</p>
-
-<p>The exception to this is when the server is configured to use <a
-href="../suexec.html">suexec</a>. This program allows CGI programs to
-be run under different user permissions, depending on which virtual
-host or user home directory they are located in. Suexec has very
-strict permission checking, and any failure in that checking will
-result in your CGI programs failing with an "Internal Server Error".
-In this case, you will need to check the suexec log file to see what
-specific security check is failing.</p>
-
-<h3><a name="pathinformation">Path information</a></h3>
-
-<p>When you run a program from your command line, you have certain
-information that is passed to the shell without you thinking about it.
-For example, you have a path, which tells the shell where it can look
-for files that you reference.</p>
-
-<p>When a program runs through the web server as a CGI program, it does
-not have that path. Any programs that you invoke in your CGI program
-(like 'sendmail', for example) will need to be specified by a full
-path, so that the shell can find them when it attempts to execute your
-CGI program.</p>
-
-<p>A common manifestation of this is the path to the script interpreter
-(often <code>perl</code>) indicated in the first line of your CGI
-program, which will look something like:</p>
-
+ <p>Also, if your program reads from, or writes to, any other
+ files, those files will need to have the correct permissions to
+ permit this.</p>
+
+ <p>The exception to this is when the server is configured to
+ use <a href="../suexec.html">suexec</a>. This program allows
+ CGI programs to be run under different user permissions,
+ depending on which virtual host or user home directory they are
+ located in. Suexec has very strict permission checking, and any
+ failure in that checking will result in your CGI programs
+ failing with an "Internal Server Error". In this case, you will
+ need to check the suexec log file to see what specific security
+ check is failing.</p>
+
+ <h3><a id="pathinformation" name="pathinformation">Path
+ information</a></h3>
+
+ <p>When you run a program from your command line, you have
+ certain information that is passed to the shell without you
+ thinking about it. For example, you have a path, which tells
+ the shell where it can look for files that you reference.</p>
+
+ <p>When a program runs through the web server as a CGI program,
+ it does not have that path. Any programs that you invoke in
+ your CGI program (like 'sendmail', for example) will need to be
+ specified by a full path, so that the shell can find them when
+ it attempts to execute your CGI program.</p>
+
+ <p>A common manifestation of this is the path to the script
+ interpreter (often <code>perl</code>) indicated in the first
+ line of your CGI program, which will look something like:</p>
<pre>
#!/usr/bin/perl
</pre>
-
-<p>Make sure that this is in fact the path to the interpreter.</p>
-<h3><a name="syntaxerrors">Syntax errors</a></h3>
+ <p>Make sure that this is in fact the path to the
+ interpreter.</p>
-<p>Most of the time when a CGI program fails, it's because of a problem
-with the program itself. This is particularly true once you get the
-hang of this CGI stuff, and no longer make the above two mistakes.
-Always attempt to run your program from the command line before you
-test if via a browser. This will eliminate most of your problems.</p>
-
-<h3><a name="errorlogs">Error logs</a></h3>
-
-<p>The error logs are your friend. Anything that goes wrong generates
-message in the error log. You should always look there first. If the
-place where you are hosting your web site does not permit you access to
-the error log, you should probably host your site somewhere else. Learn
-to read the error logs, and you'll find that almost all of your
-problems are quickly identified, and quickly solved.</p>
-
-<hr>
-<h2><a name="whatsgoingonbehindthescenes">What's going on behind
-the scenes?</a></h2>
-
-<p>As you become more advanced in CGI programming, it will become
-useful to understand more about what's happening behind the scenes.
-Specifically, how the browser and server communicate with one another.
-Because although it's all very well to write a program that prints
-``Hello, World.'', it's not particularly useful.</p>
-
-<h3><a name="environmentvariables">Environment variables</a></h3>
-
-<p>Environment variables are values that float around you as you use
-your computer. They are useful things like your path (where the
-computer searches for a the actual file implementing a command when you
-type it), your username, your terminal type, and so on. For a full list
-of your normal, every day environment variables, type <code>env</code>
-at a command prompt.</p>
-
-<p>During the CGI transaction, the server and the browser also set
-environment variables, so that they can communicate with one another.
-These are things like the browser type (Netscape, IE, Lynx), the server
-type (Apache, IIS, WebSite), the name of the CGI program that is being
-run, and so on.</p>
-
-<p>These variables are available to the CGI programmer, and are half of
-the story of the client-server communication. The complete list of
-required variables is at <a href=
-"http://hoohoo.ncsa.uiuc.edu/cgi/env.html";>http://hoohoo.ncsa.uiuc.edu/cgi/env.html</a></p>
-
-<p>This simple Perl CGI program will display all of the environment
-variables that are being passed around. Two similar programs are
-included in the <code>cgi-bin</code> directory of the Apache
-distribution. Note that some variables are required, while others are
-optional, so you may see some variables listed that were not in the
-official list. In addition, Apache provides many different ways for
-you to <a href="../env.html">add your own environment variables</a> to
-the basic ones provided by default.</p>
+ <h3><a id="syntaxerrors" name="syntaxerrors">Syntax
+ errors</a></h3>
+ <p>Most of the time when a CGI program fails, it's because of a
+ problem with the program itself. This is particularly true once
+ you get the hang of this CGI stuff, and no longer make the
+ above two mistakes. Always attempt to run your program from the
+ command line before you test if via a browser. This will
+ eliminate most of your problems.</p>
+
+ <h3><a id="errorlogs" name="errorlogs">Error logs</a></h3>
+
+ <p>The error logs are your friend. Anything that goes wrong
+ generates message in the error log. You should always look
+ there first. If the place where you are hosting your web site
+ does not permit you access to the error log, you should
+ probably host your site somewhere else. Learn to read the error
+ logs, and you'll find that almost all of your problems are
+ quickly identified, and quickly solved.</p>
+ <hr />
+
+ <h2><a id="whatsgoingonbehindthescenes"
+ name="whatsgoingonbehindthescenes">What's going on behind the
+ scenes?</a></h2>
+
+ <p>As you become more advanced in CGI programming, it will
+ become useful to understand more about what's happening behind
+ the scenes. Specifically, how the browser and server
+ communicate with one another. Because although it's all very
+ well to write a program that prints ``Hello, World.'', it's not
+ particularly useful.</p>
+
+ <h3><a id="environmentvariables"
+ name="environmentvariables">Environment variables</a></h3>
+
+ <p>Environment variables are values that float around you as
+ you use your computer. They are useful things like your path
+ (where the computer searches for a the actual file implementing
+ a command when you type it), your username, your terminal type,
+ and so on. For a full list of your normal, every day
+ environment variables, type <code>env</code> at a command
+ prompt.</p>
+
+ <p>During the CGI transaction, the server and the browser also
+ set environment variables, so that they can communicate with
+ one another. These are things like the browser type (Netscape,
+ IE, Lynx), the server type (Apache, IIS, WebSite), the name of
+ the CGI program that is being run, and so on.</p>
+
+ <p>These variables are available to the CGI programmer, and are
+ half of the story of the client-server communication. The
+ complete list of required variables is at <a
+
href="http://hoohoo.ncsa.uiuc.edu/cgi/env.html";>http://hoohoo.ncsa.uiuc.edu/cgi/env.html</a></p>
+
+ <p>This simple Perl CGI program will display all of the
+ environment variables that are being passed around. Two similar
+ programs are included in the <code>cgi-bin</code> directory of
+ the Apache distribution. Note that some variables are required,
+ while others are optional, so you may see some variables listed
+ that were not in the official list. In addition, Apache
+ provides many different ways for you to <a
+ href="../env.html">add your own environment variables</a> to
+ the basic ones provided by default.</p>
<pre>
#!/usr/bin/perl
print "Content-type: text/html\n\n";
@@ -407,93 +456,97 @@
print "$key --> $ENV{$key}<br>";
}
</pre>
-
-<h3><a name="stdinandstdout">STDIN and STDOUT</a></h3>
-<p>Other communication between the server and the client happens over
-standard input (<code>STDIN</code>) and standard output
-(<code>STDOUT</code>). In normal everyday context, <code>STDIN</code>
-means the keyboard, or a file that a program is given to act on, and
-<code>STDOUT</code> usually means the console or screen.</p>
-
-<p>When you <code>POST</code> a web form to a CGI program, the data in
-that form is bundled up into a special format and gets delivered to
-your CGI program over <code>STDIN</code>. The program then can process
-that data as though it was coming in from the keyboard, or from a
-file</p>
-
-<p>The ``special format'' is very simple. A field name and its value
-are joined together with an equals (=) sign, and pairs of values are
-joined together with an ampersand (&). Inconvenient characters like
-spaces, ampersands, and equals signs, are converted into their hex
-equivalent so that they don't gum up the works. The whole data string
-might look something like:</p>
+ <h3><a id="stdinandstdout" name="stdinandstdout">STDIN and
+ STDOUT</a></h3>
+ <p>Other communication between the server and the client
+ happens over standard input (<code>STDIN</code>) and standard
+ output (<code>STDOUT</code>). In normal everyday context,
+ <code>STDIN</code> means the keyboard, or a file that a program
+ is given to act on, and <code>STDOUT</code> usually means the
+ console or screen.</p>
+
+ <p>When you <code>POST</code> a web form to a CGI program, the
+ data in that form is bundled up into a special format and gets
+ delivered to your CGI program over <code>STDIN</code>. The
+ program then can process that data as though it was coming in
+ from the keyboard, or from a file</p>
+
+ <p>The ``special format'' is very simple. A field name and its
+ value are joined together with an equals (=) sign, and pairs of
+ values are joined together with an ampersand (&).
+ Inconvenient characters like spaces, ampersands, and equals
+ signs, are converted into their hex equivalent so that they
+ don't gum up the works. The whole data string might look
+ something like:</p>
<pre>
name=Rich%20Bowen&city=Lexington&state=KY&sidekick=Squirrel%20Monkey
</pre>
-
-<p>You'll sometimes also see this type of string appended to the a URL.
-When that is done, the server puts that string into the environment
-variable called <code>QUERY_STRING</code>. That's called a
-<code>GET</code> request. Your HTML form specifies whether a
-<code>GET</code> or a <code>POST</code> is used to deliver the data, by
-setting the <code>METHOD</code> attribute in the <code>FORM</code>
-tag.</p>
-
-<p>Your program is then responsible for splitting that string up into
-useful information. Fortunately, there are libraries and modules
-available to help you process this data, as well as handle other of the
-aspects of your CGI program.</p>
-
-<hr>
-<h2><a name="cgimoduleslibraries">CGI modules/libraries</a></h2>
-
-<p>When you write CGI programs, you should consider using a code
-library, or module, to do most of the grunt work for you. This leads to
-fewer errors, and faster development.</p>
-
-<p>If you're writing CGI programs in Perl, modules are available on <a
-href="http://www.cpan.org/";>CPAN</a>. The most popular module for this
-purpose is CGI.pm. You might also consider CGI::Lite, which implements
-a minimal set of functionality, which is all you need in most
-programs.</p>
-
-<p>If you're writing CGI programs in C, there are a variety of options.
-One of these is the CGIC library, from <a href=
-"http://www.boutell.com/cgic/";>http://www.boutell.com/cgic/</a></p>
-
-<hr>
-<h2><a name="formoreinformation">For more information</a></h2>
-
-<p>There are a large number of CGI resources on the web. You can
-discuss CGI problems with other users on the Usenet group
-comp.infosystems.www.authoring.cgi. And the -servers mailing list from
-the HTML Writers Guild is a great source of answers to your questions.
-You can find out more at <a href=
-"http://www.hwg.org/lists/hwg-servers/";>http://www.hwg.org/lists/hwg-servers/</a></p>
-
-<p>And, of course, you should probably read the CGI specification,
-which has all the details on the operation of CGI programs. You can
-find the original version at the <a href=
-"http://hoohoo.ncsa.uiuc.edu/cgi/interface.html";>NCSA</a> and there is
-an updated draft at the <a
-href="http://web.golux.com/coar/cgi/";>Common Gateway Interface RFC
-project</a>.</p>
-
-<p>When you post a question about a CGI problem that you're having,
-whether to a mailing list, or to a newsgroup, make sure you provide
-enough information about what happened, what you expected to happen,
-and how what actually happened was different, what server you're
-running, what language your CGI program was in, and, if possible, the
-offending code. This will make finding your problem much simpler.</p>
-
-<p>Note that questions about CGI problems should <strong>never</strong>
-be posted to the Apache bug database unless you are sure you have found
-a problem in the Apache source code.</p>
-
-<!--#include virtual="footer.html" -->
-</body>
+ <p>You'll sometimes also see this type of string appended to
+ the a URL. When that is done, the server puts that string into
+ the environment variable called <code>QUERY_STRING</code>.
+ That's called a <code>GET</code> request. Your HTML form
+ specifies whether a <code>GET</code> or a <code>POST</code> is
+ used to deliver the data, by setting the <code>METHOD</code>
+ attribute in the <code>FORM</code> tag.</p>
+
+ <p>Your program is then responsible for splitting that string
+ up into useful information. Fortunately, there are libraries
+ and modules available to help you process this data, as well as
+ handle other of the aspects of your CGI program.</p>
+ <hr />
+
+ <h2><a id="cgimoduleslibraries" name="cgimoduleslibraries">CGI
+ modules/libraries</a></h2>
+
+ <p>When you write CGI programs, you should consider using a
+ code library, or module, to do most of the grunt work for you.
+ This leads to fewer errors, and faster development.</p>
+
+ <p>If you're writing CGI programs in Perl, modules are
+ available on <a href="http://www.cpan.org/";>CPAN</a>. The most
+ popular module for this purpose is CGI.pm. You might also
+ consider CGI::Lite, which implements a minimal set of
+ functionality, which is all you need in most programs.</p>
+
+ <p>If you're writing CGI programs in C, there are a variety of
+ options. One of these is the CGIC library, from <a
+ href="http://www.boutell.com/cgic/";>http://www.boutell.com/cgic/</a></p>
+ <hr />
+
+ <h2><a id="formoreinformation" name="formoreinformation">For
+ more information</a></h2>
+
+ <p>There are a large number of CGI resources on the web. You
+ can discuss CGI problems with other users on the Usenet group
+ comp.infosystems.www.authoring.cgi. And the -servers mailing
+ list from the HTML Writers Guild is a great source of answers
+ to your questions. You can find out more at <a
+
href="http://www.hwg.org/lists/hwg-servers/";>http://www.hwg.org/lists/hwg-servers/</a></p>
+
+ <p>And, of course, you should probably read the CGI
+ specification, which has all the details on the operation of
+ CGI programs. You can find the original version at the <a
+ href="http://hoohoo.ncsa.uiuc.edu/cgi/interface.html";>NCSA</a>
+ and there is an updated draft at the <a
+ href="http://web.golux.com/coar/cgi/";>Common Gateway Interface
+ RFC project</a>.</p>
+
+ <p>When you post a question about a CGI problem that you're
+ having, whether to a mailing list, or to a newsgroup, make sure
+ you provide enough information about what happened, what you
+ expected to happen, and how what actually happened was
+ different, what server you're running, what language your CGI
+ program was in, and, if possible, the offending code. This will
+ make finding your problem much simpler.</p>
+
+ <p>Note that questions about CGI problems should
+ <strong>never</strong> be posted to the Apache bug database
+ unless you are sure you have found a problem in the Apache
+ source code.</p>
+ <!--#include virtual="footer.html" -->
+ </body>
</html>
1.2 +3 -0 httpd-docs-1.3/htdocs/manual/howto/cgi.html.html
Index: cgi.html.html
===================================================================
RCS file: /home/cvs/httpd-docs-1.3/htdocs/manual/howto/cgi.html.html,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- cgi.html.html 2001/02/10 21:59:15 1.1
+++ cgi.html.html 2001/10/08 01:23:28 1.2
@@ -1 +1,4 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
+ "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd";>
<!--#include virtual="cgi.html.en" -->
+
1.2 +17 -6 httpd-docs-1.3/htdocs/manual/howto/footer.html
Index: footer.html
===================================================================
RCS file: /home/cvs/httpd-docs-1.3/htdocs/manual/howto/footer.html,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- footer.html 2000/11/05 20:59:14 1.1
+++ footer.html 2001/10/08 01:23:28 1.2
@@ -1,8 +1,19 @@
-<HR>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
+ "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd";>
-<H3 ALIGN="CENTER">
- Apache HTTP Server Version 1.3
-</H3>
+<html xmlns="http://www.w3.org/1999/xhtml";>
+ <head>
+ <meta name="generator" content="HTML Tidy, see www.w3.org" />
-<A HREF="./"><IMG SRC="../images/index.gif" ALT="Index"></A>
-<A HREF="../"><IMG SRC="../images/home.gif" ALT="Home"></A>
+ <title></title>
+ </head>
+
+ <body>
+ <hr />
+
+ <h3 align="CENTER">Apache HTTP Server Version 1.3</h3>
+ <a href="./"><img src="../images/index.gif" alt="Index" /></a>
+ <a href="../"><img src="../images/home.gif" alt="Home" /></a>
+ </body>
+</html>
+
1.2 +19 -6 httpd-docs-1.3/htdocs/manual/howto/header.html
Index: header.html
===================================================================
RCS file: /home/cvs/httpd-docs-1.3/htdocs/manual/howto/header.html,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- header.html 2000/11/05 20:59:14 1.1
+++ header.html 2001/10/08 01:23:28 1.2
@@ -1,6 +1,19 @@
-<DIV ALIGN="CENTER">
- <IMG SRC="../images/sub.gif" ALT="[APACHE DOCUMENTATION]">
- <H3>
- Apache HTTP Server Version 1.3
- </H3>
-</DIV>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
+ "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd";>
+
+<html xmlns="http://www.w3.org/1999/xhtml";>
+ <head>
+ <meta name="generator" content="HTML Tidy, see www.w3.org" />
+
+ <title></title>
+ </head>
+
+ <body>
+ <div align="CENTER">
+ <img src="../images/sub.gif" alt="[APACHE DOCUMENTATION]" />
+
+ <h3>Apache HTTP Server Version 1.3</h3>
+ </div>
+ </body>
+</html>
+
1.8 +423 -394 httpd-docs-1.3/htdocs/manual/howto/ssi.html.en
Index: ssi.html.en
===================================================================
RCS file: /home/cvs/httpd-docs-1.3/htdocs/manual/howto/ssi.html.en,v
retrieving revision 1.7
retrieving revision 1.8
diff -u -r1.7 -r1.8
--- ssi.html.en 2001/01/24 18:13:37 1.7
+++ ssi.html.en 2001/10/08 01:23:28 1.8
@@ -1,492 +1,521 @@
-<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
-<html>
-<head>
-<title>Apache Tutorial: Introduction to Server Side Includes</title>
-<link rev="made" href="mailto:[EMAIL PROTECTED]">
-</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">Apache Tutorial: Introduction to Server Side
-Includes</h1>
-
-<a name="__index__"></a> <!-- INDEX BEGIN -->
-
-
-<ul>
-<li><a href=
-"#apachetutorial:introductiontoserversideincludes">Apache
-Tutorial: Introduction to Server Side Includes</a></li>
-
-<li><a href="#whataressi">What are SSI?</a></li>
-
-<li><a href="#configuringyourservertopermitssi">Configuring your
-server to permit SSI</a></li>
-
-<li><a href="#basicssidirectives">Basic SSI directives</a>
-
-<ul>
- <li><a href="#today'sdate">Today's date</a></li>
-
- <li><a href="#modificationdateofthefile">Modification date of the
-file</a></li>
-
- <li><a href="#includingtheresultsofacgiprogram">Including the
-results of a CGI program</a></li>
-</ul>
-</li>
-
-<li><a href="#additionalexamples">Additional examples</a>
-
-<ul>
-<li><a href="#whenwasthisdocumentmodified">When was this document
-modified?</a></li>
-
-<li><a href="#includingastandardfooter">Including a standard
-footer</a></li>
-
-<li><a href="#whatelsecaniconfig">What else can I config?</a></li>
-
-<li><a href="#executingcommands">Executing commands</a></li>
-</ul>
-</li>
-
-<li><a href="#advancedssitechniques">Advanced SSI techniques</a>
-
-<ul>
-<li><a href="#settingvariables">Setting variables</a></li>
-
-<li><a href="#conditionalexpressions">Conditional expressions</a></li>
-</ul>
-</li>
-
-<li><a href="#conclusion">Conclusion</a></li>
-</ul>
-
-<!-- INDEX END -->
-<hr>
-<h2><a name=
-"apachetutorial:introductiontoserversideincludes">Apache
-Tutorial: Introduction to Server Side Includes</a></h2>
-
-<table border="1">
-<tr>
-<td valign="top"><strong>Related Modules</strong><br>
-<br>
- <a href="../mod/mod_include.html">mod_include</a><br>
-<a href="../mod/mod_cgi.html">mod_cgi</a><br>
-<a href="../mod/mod_expires.html">mod_expires</a><br>
- </td>
-<td valign="top"><strong>Related Directives</strong><br>
-<br>
- <a href="../mod/core.html#options">Options</a><br>
-<a href="../mod/mod_include.html#xbithack">XBitHack</a><br>
-<a href="../mod/mod_mime.html#addtype">AddType</a><br>
-<a href="../mod/mod_mime.html#addhandler">AddHandler</a><br>
-<a href=
-"../mod/mod_setenvif.html#BrowserMatchNoCase">BrowserMatchNoCase</a><br>
-
- </td>
-</tr>
-</table>
-
-<p>This HOWTO first appeared in Apache Today
-(http://www.apachetoday.com/) as a series of three articles. They
-appear here by arrangement with ApacheToday and Internet.com.</p>
-
-<p>This article deals with Server Side Includes, usually called simply
-SSI. In this article, I'll talk about configuring your server to permit
-SSI, and introduce some basic SSI techniques for adding dynamic content
-to your existing HTML pages.</p>
-
-<p>In the latter part of the article, we'll talk about some of the
-somewhat more advanced things that can be done with SSI, such as
-conditional statements in your SSI directives.</p>
-
-<hr>
-<h2><a name="whataressi">What are SSI?</a></h2>
-
-<p>SSI (Server Side Includes) are directives that are placed in HTML
-pages, and evaluated on the server while the pages are being served.
-They let you add dynamically generated content to an existing HTML
-page, without having to serve the entire page via a CGI program, or
-other dynamic technology.</p>
-
-<p>The decision of when to use SSI, and when to have your page entirely
-generated by some program, is usually a matter of how much of the page
-is static, and how much needs to be recalculated every time the page is
-served. SSI is a great way to add small pieces of information, such as
-the current time. But if a majority of your page is being generated at
-the time that it is served, you need to look for some other
-solution.</p>
-
-<hr>
-<h2><a name="configuringyourservertopermitssi">Configuring your
-server to permit SSI</a></h2>
-
-<p>To permit SSI on your server, you must have the following directive
-either in your <code>httpd.conf</code> file, or in a
-<code>.htaccess</code> file:</p>
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
+ "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd";>
+<html xmlns="http://www.w3.org/1999/xhtml";>
+ <head>
+ <meta name="generator" content="HTML Tidy, see www.w3.org" />
+
+ <title>Apache Tutorial: Introduction to Server Side
+ Includes</title>
+ <link rev="made" href="mailto:[EMAIL PROTECTED]" />
+ </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">Apache Tutorial: Introduction to Server Side
+ Includes</h1>
+ <a id="__index__" name="__index__"></a> <!-- INDEX BEGIN -->
+
+
+ <ul>
+ <li><a
+ href="#apachetutorial:introductiontoserversideincludes">Apache
+ Tutorial: Introduction to Server Side Includes</a></li>
+
+ <li><a href="#whataressi">What are SSI?</a></li>
+
+ <li><a href="#configuringyourservertopermitssi">Configuring
+ your server to permit SSI</a></li>
+
+ <li>
+ <a href="#basicssidirectives">Basic SSI directives</a>
+
+ <ul>
+ <li><a href="#today'sdate">Today's date</a></li>
+
+ <li><a href="#modificationdateofthefile">Modification
+ date of the file</a></li>
+
+ <li><a href="#includingtheresultsofacgiprogram">Including
+ the results of a CGI program</a></li>
+ </ul>
+ </li>
+
+ <li>
+ <a href="#additionalexamples">Additional examples</a>
+
+ <ul>
+ <li><a href="#whenwasthisdocumentmodified">When was this
+ document modified?</a></li>
+
+ <li><a href="#includingastandardfooter">Including a
+ standard footer</a></li>
+
+ <li><a href="#whatelsecaniconfig">What else can I
+ config?</a></li>
+
+ <li><a href="#executingcommands">Executing
+ commands</a></li>
+ </ul>
+ </li>
+
+ <li>
+ <a href="#advancedssitechniques">Advanced SSI
+ techniques</a>
+
+ <ul>
+ <li><a href="#settingvariables">Setting
+ variables</a></li>
+
+ <li><a href="#conditionalexpressions">Conditional
+ expressions</a></li>
+ </ul>
+ </li>
+
+ <li><a href="#conclusion">Conclusion</a></li>
+ </ul>
+ <!-- INDEX END -->
+ <hr />
+
+ <h2><a id="apachetutorial:introductiontoserversideincludes"
+ name="apachetutorial:introductiontoserversideincludes">Apache
+ Tutorial: Introduction to Server Side Includes</a></h2>
+
+ <table border="1">
+ <tr>
+ <td valign="top"><strong>Related Modules</strong><br />
+ <br />
+ <a href="../mod/mod_include.html">mod_include</a><br />
+ <a href="../mod/mod_cgi.html">mod_cgi</a><br />
+ <a href="../mod/mod_expires.html">mod_expires</a><br />
+ </td>
+
+ <td valign="top"><strong>Related Directives</strong><br />
+ <br />
+ <a href="../mod/core.html#options">Options</a><br />
+ <a
+ href="../mod/mod_include.html#xbithack">XBitHack</a><br />
+ <a href="../mod/mod_mime.html#addtype">AddType</a><br />
+ <a
+ href="../mod/mod_mime.html#addhandler">AddHandler</a><br />
+ <a
+
href="../mod/mod_setenvif.html#BrowserMatchNoCase">BrowserMatchNoCase</a><br />
+ </td>
+ </tr>
+ </table>
+
+ <p>This HOWTO first appeared in Apache Today
+ (http://www.apachetoday.com/) as a series of three articles.
+ They appear here by arrangement with ApacheToday and
+ Internet.com.</p>
+
+ <p>This article deals with Server Side Includes, usually called
+ simply SSI. In this article, I'll talk about configuring your
+ server to permit SSI, and introduce some basic SSI techniques
+ for adding dynamic content to your existing HTML pages.</p>
+
+ <p>In the latter part of the article, we'll talk about some of
+ the somewhat more advanced things that can be done with SSI,
+ such as conditional statements in your SSI directives.</p>
+ <hr />
+
+ <h2><a id="whataressi" name="whataressi">What are SSI?</a></h2>
+
+ <p>SSI (Server Side Includes) are directives that are placed in
+ HTML pages, and evaluated on the server while the pages are
+ being served. They let you add dynamically generated content to
+ an existing HTML page, without having to serve the entire page
+ via a CGI program, or other dynamic technology.</p>
+
+ <p>The decision of when to use SSI, and when to have your page
+ entirely generated by some program, is usually a matter of how
+ much of the page is static, and how much needs to be
+ recalculated every time the page is served. SSI is a great way
+ to add small pieces of information, such as the current time.
+ But if a majority of your page is being generated at the time
+ that it is served, you need to look for some other
+ solution.</p>
+ <hr />
+
+ <h2><a id="configuringyourservertopermitssi"
+ name="configuringyourservertopermitssi">Configuring your server
+ to permit SSI</a></h2>
+
+ <p>To permit SSI on your server, you must have the following
+ directive either in your <code>httpd.conf</code> file, or in a
+ <code>.htaccess</code> file:</p>
<pre>
Options +Includes
</pre>
-<p>This tells Apache that you want to permit files to be parsed for SSI
-directives.</p>
+ <p>This tells Apache that you want to permit files to be parsed
+ for SSI directives.</p>
-<p>Not just any file is parsed for SSI directives. You have to tell
-Apache which files should be parsed. There are two ways to do this. You
-can tell Apache to parse any file with a particular file extension,
-such as <code>.shtml</code>, with the following directives:</p>
-
+ <p>Not just any file is parsed for SSI directives. You have to
+ tell Apache which files should be parsed. There are two ways to
+ do this. You can tell Apache to parse any file with a
+ particular file extension, such as <code>.shtml</code>, with
+ the following directives:</p>
<pre>
AddType text/html .shtml
AddHandler server-parsed .shtml
</pre>
-
-<p>One disadvantage to this approach is that if you wanted to add SSI
-directives to an existing page, you would have to change the name of
-that page, and all links to that page, in order to give it a
-<code>.shtml</code> extension, so that those directives would be
-executed.</p>
-<p>The other method is to use the <code>XBitHack</code> directive:</p>
+ <p>One disadvantage to this approach is that if you wanted to
+ add SSI directives to an existing page, you would have to
+ change the name of that page, and all links to that page, in
+ order to give it a <code>.shtml</code> extension, so that those
+ directives would be executed.</p>
+ <p>The other method is to use the <code>XBitHack</code>
+ directive:</p>
<pre>
XBitHack on
</pre>
-<p><code>XBitHack</code> tells Apache to parse files for SSI directives
-if they have the execute bit set. So, to add SSI directives to an
-existing page, rather than having to change the file name, you would
-just need to make the file executable using <code>chmod</code>.</p>
-
+ <p><code>XBitHack</code> tells Apache to parse files for SSI
+ directives if they have the execute bit set. So, to add SSI
+ directives to an existing page, rather than having to change
+ the file name, you would just need to make the file executable
+ using <code>chmod</code>.</p>
<pre>
chmod +x pagename.html
</pre>
-
-<p>A brief comment about what not to do. You'll occasionally see people
-recommending that you just tell Apache to parse all <code>.html</code>
-files for SSI, so that you don't have to mess with <code>.shtml</code>
-file names. These folks have perhaps not heard about
-<code>XBitHack</code>. The thing to keep in mind is that, by doing
-this, you're requiring that Apache read through every single file that
-it sends out to clients, even if they don't contain any SSI directives.
-This can slow things down quite a bit, and is not a good idea.</p>
-
-<p>Of course, on Windows, there is no such thing as an execute bit to
-set, so that limits your options a little.</p>
-
-<p>In its default configuration, Apache does not send the last modified
-date or content length HTTP headers on SSI pages, because these values are
-difficult to calculate for dynamic content. This can prevent your
-document from being cached, and result in slower perceived client
-performance. There are two ways to solve this:</p>
-
-<ol>
-
-<li>Use the <code>XBitHack Full</code> configuration. This tells
-Apache to determine the last modified date by looking only at the date
-of the originally requested file, ignoring the modification date of
-any included files. </li>
-
-<li>Use the directives provided by <a
-href="../mod/mod_expires.html">mod_expires</a> to set an explicit
-expiration time on your files, thereby letting browsers and proxies
-know that it is acceptable to cache them. </li>
-</ol>
+ <p>A brief comment about what not to do. You'll occasionally
+ see people recommending that you just tell Apache to parse all
+ <code>.html</code> files for SSI, so that you don't have to
+ mess with <code>.shtml</code> file names. These folks have
+ perhaps not heard about <code>XBitHack</code>. The thing to
+ keep in mind is that, by doing this, you're requiring that
+ Apache read through every single file that it sends out to
+ clients, even if they don't contain any SSI directives. This
+ can slow things down quite a bit, and is not a good idea.</p>
+
+ <p>Of course, on Windows, there is no such thing as an execute
+ bit to set, so that limits your options a little.</p>
+
+ <p>In its default configuration, Apache does not send the last
+ modified date or content length HTTP headers on SSI pages,
+ because these values are difficult to calculate for dynamic
+ content. This can prevent your document from being cached, and
+ result in slower perceived client performance. There are two
+ ways to solve this:</p>
+
+ <ol>
+ <li>Use the <code>XBitHack Full</code> configuration. This
+ tells Apache to determine the last modified date by looking
+ only at the date of the originally requested file, ignoring
+ the modification date of any included files.</li>
+
+ <li>Use the directives provided by <a
+ href="../mod/mod_expires.html">mod_expires</a> to set an
+ explicit expiration time on your files, thereby letting
+ browsers and proxies know that it is acceptable to cache
+ them.</li>
+ </ol>
+ <hr />
+ <h2><a id="basicssidirectives" name="basicssidirectives">Basic
+ SSI directives</a></h2>
-<hr>
-<h2><a name="basicssidirectives">Basic SSI directives</a></h2>
-
-<p>SSI directives have the following syntax:</p>
-
+ <p>SSI directives have the following syntax:</p>
<pre>
<!--#element attribute=value attribute=value ... -->
</pre>
-
-<p>It is formatted like an HTML comment, so if you don't have SSI
-correctly enabled, the browser will ignore it, but it will still be
-visible in the HTML source. If you have SSI correctly configured, the
-directive will be replaced with its results.</p>
-
-<p>The element can be one of a number of things, and we'll talk some
-more about most of these in the next installment of this series. For
-now, here are some examples of what you can do with SSI</p>
-<h3><a name="today'sdate">Today's date</a></h3>
+ <p>It is formatted like an HTML comment, so if you don't have
+ SSI correctly enabled, the browser will ignore it, but it will
+ still be visible in the HTML source. If you have SSI correctly
+ configured, the directive will be replaced with its
+ results.</p>
+
+ <p>The element can be one of a number of things, and we'll talk
+ some more about most of these in the next installment of this
+ series. For now, here are some examples of what you can do with
+ SSI</p>
+ <h3><a id="today'sdate" name="today'sdate">Today's
+ date</a></h3>
<pre>
<!--#echo var="DATE_LOCAL" -->
</pre>
-<p>The <code>echo</code> element just spits out the value of a
-variable. There are a number of standard variables, which include the
-whole set of environment variables that are available to CGI programs.
-Also, you can define your own variables with the <code>set</code>
-element.</p>
-
-<p>If you don't like the format in which the date gets printed, you can
-use the <code>config</code> element, with a <code>timefmt</code>
-attribute, to modify that formatting.</p>
-
+ <p>The <code>echo</code> element just spits out the value of a
+ variable. There are a number of standard variables, which
+ include the whole set of environment variables that are
+ available to CGI programs. Also, you can define your own
+ variables with the <code>set</code> element.</p>
+
+ <p>If you don't like the format in which the date gets printed,
+ you can use the <code>config</code> element, with a
+ <code>timefmt</code> attribute, to modify that formatting.</p>
<pre>
<!--#config timefmt="%A %B %d, %Y" -->
Today is <!--#echo var="DATE_LOCAL" -->
</pre>
-
-<h3><a name="modificationdateofthefile">Modification date of the
-file</a></h3>
+ <h3><a id="modificationdateofthefile"
+ name="modificationdateofthefile">Modification date of the
+ file</a></h3>
<pre>
This document last modified <!--#flastmod file="index.html" -->
</pre>
-
-<p>This element is also subject to <code>timefmt</code> format
-configurations.</p>
-<h3><a name="includingtheresultsofacgiprogram">Including the
-results of a CGI program</a></h3>
+ <p>This element is also subject to <code>timefmt</code> format
+ configurations.</p>
-<p>This is one of the more common uses of SSI - to output the results
-of a CGI program, such as everybody's favorite, a ``hit counter.''</p>
-
+ <h3><a id="includingtheresultsofacgiprogram"
+ name="includingtheresultsofacgiprogram">Including the results
+ of a CGI program</a></h3>
+
+ <p>This is one of the more common uses of SSI - to output the
+ results of a CGI program, such as everybody's favorite, a ``hit
+ counter.''</p>
<pre>
<!--#include virtual="/cgi-bin/counter.pl" -->
</pre>
-
-<hr>
-<h2><a name="additionalexamples">Additional examples</a></h2>
-
-<p>Following are some specific examples of things you can do in your
-HTML documents with SSI.</p>
+ <hr />
-<hr>
-<h2><a name="whenwasthisdocumentmodified">When was this document
-modified?</a></h2>
-
-<p>Earlier, we mentioned that you could use SSI to inform the user when
-the document was most recently modified. However, the actual method for
-doing that was left somewhat in question. The following code, placed in
-your HTML document, will put such a time stamp on your page. Of course,
-you will have to have SSI correctly enabled, as discussed above.</p>
+ <h2><a id="additionalexamples"
+ name="additionalexamples">Additional examples</a></h2>
+ <p>Following are some specific examples of things you can do in
+ your HTML documents with SSI.</p>
+ <hr />
+
+ <h2><a id="whenwasthisdocumentmodified"
+ name="whenwasthisdocumentmodified">When was this document
+ modified?</a></h2>
+
+ <p>Earlier, we mentioned that you could use SSI to inform the
+ user when the document was most recently modified. However, the
+ actual method for doing that was left somewhat in question. The
+ following code, placed in your HTML document, will put such a
+ time stamp on your page. Of course, you will have to have SSI
+ correctly enabled, as discussed above.</p>
<pre>
<!--#config timefmt="%A %B %d, %Y" -->
This file last modified <!--#flastmod file="ssi.shtml" -->
</pre>
-<p>Of course, you will need to replace the <code>ssi.shtml</code> with
-the actual name of the file that you're referring to. This can be
-inconvenient if you're just looking for a generic piece of code that
-you can paste into any file, so you probably want to use the
-<code>LAST_MODIFIED</code> variable instead:</p>
-
+ <p>Of course, you will need to replace the
+ <code>ssi.shtml</code> with the actual name of the file that
+ you're referring to. This can be inconvenient if you're just
+ looking for a generic piece of code that you can paste into any
+ file, so you probably want to use the
+ <code>LAST_MODIFIED</code> variable instead:</p>
<pre>
<!--#config timefmt="%D" -->
This file last modified <!--#echo var="LAST_MODIFIED" -->
</pre>
-
-<p>For more details on the <code>timefmt</code> format, go to your
-favorite search site and look for <code>ctime</code>. The syntax is the
-same.</p>
-
-<hr>
-<h2><a name="includingastandardfooter">Including a standard
-footer</a></h2>
-
-<p>If you are managing any site that is more than a few pages, you may
-find that making changes to all those pages can be a real pain,
-particularly if you are trying to maintain some kind of standard look
-across all those pages.</p>
-
-<p>Using an include file for a header and/or a footer can reduce the
-burden of these updates. You just have to make one footer file, and
-then include it into each page with the <code>include</code> SSI
-command. The <code>include</code> element can determine what file to
-include with either the <code>file</code> attribute, or the
-<code>virtual</code> attribute. The <code>file</code> attribute is a
-file path, <em>relative to the current directory</em>. That means that
-it cannot be an absolute file path (starting with /), nor can it
-contain ../ as part of that path. The <code>virtual</code> attribute is
-probably more useful, and should specify a URL relative to the document
-being served. It can start with a /, but must be on the same server as
-the file being served.</p>
+ <p>For more details on the <code>timefmt</code> format, go to
+ your favorite search site and look for <code>ctime</code>. The
+ syntax is the same.</p>
+ <hr />
+
+ <h2><a id="includingastandardfooter"
+ name="includingastandardfooter">Including a standard
+ footer</a></h2>
+
+ <p>If you are managing any site that is more than a few pages,
+ you may find that making changes to all those pages can be a
+ real pain, particularly if you are trying to maintain some kind
+ of standard look across all those pages.</p>
+
+ <p>Using an include file for a header and/or a footer can
+ reduce the burden of these updates. You just have to make one
+ footer file, and then include it into each page with the
+ <code>include</code> SSI command. The <code>include</code>
+ element can determine what file to include with either the
+ <code>file</code> attribute, or the <code>virtual</code>
+ attribute. The <code>file</code> attribute is a file path,
+ <em>relative to the current directory</em>. That means that it
+ cannot be an absolute file path (starting with /), nor can it
+ contain ../ as part of that path. The <code>virtual</code>
+ attribute is probably more useful, and should specify a URL
+ relative to the document being served. It can start with a /,
+ but must be on the same server as the file being served.</p>
<pre>
<!--#include virtual="/footer.html" -->
</pre>
-<p>I'll frequently combine the last two things, putting a
-<code>LAST_MODIFIED</code> directive inside a footer file to be
-included. SSI directives can be contained in the included file, and
-includes can be nested - that is, the included file can include another
-file, and so on.</p>
+ <p>I'll frequently combine the last two things, putting a
+ <code>LAST_MODIFIED</code> directive inside a footer file to be
+ included. SSI directives can be contained in the included file,
+ and includes can be nested - that is, the included file can
+ include another file, and so on.</p>
+ <hr />
-<hr>
-<h2><a name="whatelsecaniconfig">What else can I config?</a></h2>
+ <h2><a id="whatelsecaniconfig" name="whatelsecaniconfig">What
+ else can I config?</a></h2>
-<p>In addition to being able to <code>config</code> the time format,
-you can also <code>config</code> two other things.</p>
+ <p>In addition to being able to <code>config</code> the time
+ format, you can also <code>config</code> two other things.</p>
-<p>Usually, when something goes wrong with your SSI directive, you get
-the message</p>
-
+ <p>Usually, when something goes wrong with your SSI directive,
+ you get the message</p>
<pre>
[an error occurred while processing this directive]
</pre>
-
-<p>If you want to change that message to something else, you can do so
-with the <code>errmsg</code> attribute to the <code>config</code>
-element:</p>
+ <p>If you want to change that message to something else, you
+ can do so with the <code>errmsg</code> attribute to the
+ <code>config</code> element:</p>
<pre>
<!--#config errmsg="[It appears that you don't know how to use
SSI]" -->
</pre>
-<p>Hopefully, end users will never see this message, because you will
-have resolved all the problems with your SSI directives before your
-site goes live. (Right?)</p>
-
-<p>And you can <code>config</code> the format in which file sizes are
-returned with the <code>sizefmt</code> attribute. You can specify
-<code>bytes</code> for a full count in bytes, or <code>abbrev</code>
-for an abbreviated number in Kb or Mb, as appropriate.</p>
-
-<hr>
-<h2><a name="executingcommands">Executing commands</a></h2>
-
-<p>I expect that I'll have an article some time in the coming months
-about using SSI with small CGI programs. For now, here's something else
-that you can do with the <code>exec</code> element. You can actually
-have SSI execute a command using the shell (<code>/bin/sh</code>, to be
-precise - or the DOS shell, if you're on Win32). The following, for
-example, will give you a directory listing.</p>
-
+ <p>Hopefully, end users will never see this message, because
+ you will have resolved all the problems with your SSI
+ directives before your site goes live. (Right?)</p>
+
+ <p>And you can <code>config</code> the format in which file
+ sizes are returned with the <code>sizefmt</code> attribute. You
+ can specify <code>bytes</code> for a full count in bytes, or
+ <code>abbrev</code> for an abbreviated number in Kb or Mb, as
+ appropriate.</p>
+ <hr />
+
+ <h2><a id="executingcommands"
+ name="executingcommands">Executing commands</a></h2>
+
+ <p>I expect that I'll have an article some time in the coming
+ months about using SSI with small CGI programs. For now, here's
+ something else that you can do with the <code>exec</code>
+ element. You can actually have SSI execute a command using the
+ shell (<code>/bin/sh</code>, to be precise - or the DOS shell,
+ if you're on Win32). The following, for example, will give you
+ a directory listing.</p>
<pre>
<pre>
<!--#exec cmd="ls" -->
</pre>
</pre>
-
-<p>or, on Windows</p>
+ <p>or, on Windows</p>
<pre>
<pre>
<!--#exec cmd="dir" -->
</pre>
</pre>
-
-<p>You might notice some strange formatting with this directive on
-Windows, because the output from <code>dir</code> contains the string
-``<<code>dir</code>>'' in it, which confuses browsers.</p>
-
-<p>Note that this feature is exceedingly dangerous, as it will execute
-whatever code happens to be embedded in the <code>exec</code> tag. If
-you have any situation where users can edit content on your web pages,
-such as with a ``guestbook'', for example, make sure that you have this
-feature disabled. You can allow SSI, but not the <code>exec</code>
-feature, with the <code>IncludesNOEXEC</code> argument to the
-<code>Options</code> directive.</p>
-
-<hr>
-<h2><a name="advancedssitechniques">Advanced SSI techniques</a></h2>
-
-<p>In addition to spitting out content, Apache SSI gives you the option
-of setting variables, and using those variables in comparisons and
-conditionals.</p>
-
-<h3><a name="caveat">Caveat</a></h3>
-
-<p>Most of the features discussed in this article are only available to
-you if you are running Apache 1.2 or later. Of course, if you are not
-running Apache 1.2 or later, you need to upgrade immediately, if not
-sooner. Go on. Do it now. We'll wait.</p>
-
-<hr>
-<h2><a name="settingvariables">Setting variables</a></h2>
-
-<p>Using the <code>set</code> directive, you can set variables for
-later use. We'll need this later in the discussion, so we'll talk about
-it here. The syntax of this is as follows:</p>
+ <p>You might notice some strange formatting with this directive
+ on Windows, because the output from <code>dir</code> contains
+ the string ``<<code>dir</code>>'' in it, which confuses
+ browsers.</p>
+
+ <p>Note that this feature is exceedingly dangerous, as it will
+ execute whatever code happens to be embedded in the
+ <code>exec</code> tag. If you have any situation where users
+ can edit content on your web pages, such as with a
+ ``guestbook'', for example, make sure that you have this
+ feature disabled. You can allow SSI, but not the
+ <code>exec</code> feature, with the <code>IncludesNOEXEC</code>
+ argument to the <code>Options</code> directive.</p>
+ <hr />
+
+ <h2><a id="advancedssitechniques"
+ name="advancedssitechniques">Advanced SSI techniques</a></h2>
+
+ <p>In addition to spitting out content, Apache SSI gives you
+ the option of setting variables, and using those variables in
+ comparisons and conditionals.</p>
+
+ <h3><a id="caveat" name="caveat">Caveat</a></h3>
+
+ <p>Most of the features discussed in this article are only
+ available to you if you are running Apache 1.2 or later. Of
+ course, if you are not running Apache 1.2 or later, you need to
+ upgrade immediately, if not sooner. Go on. Do it now. We'll
+ wait.</p>
+ <hr />
+
+ <h2><a id="settingvariables" name="settingvariables">Setting
+ variables</a></h2>
+
+ <p>Using the <code>set</code> directive, you can set variables
+ for later use. We'll need this later in the discussion, so
+ we'll talk about it here. The syntax of this is as follows:</p>
<pre>
<!--#set var="name" value="Rich" -->
</pre>
-<p>In addition to merely setting values literally like that, you can
-use any other variable, including, for example, environment variables,
-or some of the variables we discussed in the last article (like
-<code>LAST_MODIFIED</code>, for example) to give values to your
-variables. You will specify that something is a variable, rather than a
-literal string, by using the dollar sign ($) before the name of the
-variable.</p>
-
+ <p>In addition to merely setting values literally like that,
+ you can use any other variable, including, for example,
+ environment variables, or some of the variables we discussed in
+ the last article (like <code>LAST_MODIFIED</code>, for example)
+ to give values to your variables. You will specify that
+ something is a variable, rather than a literal string, by using
+ the dollar sign ($) before the name of the variable.</p>
<pre>
<!--#set var="modified" value="$LAST_MODIFIED" -->
</pre>
-
-<p>To put a literal dollar sign into the value of your variable, you
-need to escape the dollar sign with a backslash.</p>
+ <p>To put a literal dollar sign into the value of your
+ variable, you need to escape the dollar sign with a
+ backslash.</p>
<pre>
<!--#set var="cost" value="\$100" -->
</pre>
-
-<p>Finally, if you want to put a variable in the midst of a longer
-string, and there's a chance that the name of the variable will run up
-against some other characters, and thus be confused with those
-characters, you can place the name of the variable in braces, to remove
-this confusion. (It's hard to come up with a really good example of
-this, but hopefully you'll get the point.)</p>
+ <p>Finally, if you want to put a variable in the midst of a
+ longer string, and there's a chance that the name of the
+ variable will run up against some other characters, and thus be
+ confused with those characters, you can place the name of the
+ variable in braces, to remove this confusion. (It's hard to
+ come up with a really good example of this, but hopefully
+ you'll get the point.)</p>
<pre>
<!--#set var="date" value="${DATE_LOCAL}_${DATE_GMT}" -->
</pre>
+ <hr />
-<hr>
-<h2><a name="conditionalexpressions">Conditional expressions</a></h2>
+ <h2><a id="conditionalexpressions"
+ name="conditionalexpressions">Conditional expressions</a></h2>
-<p>Now that we have variables, and are able to set and compare their
-values, we can use them to express conditionals. This lets SSI be a
-tiny programming language of sorts. <code>mod_include</code> provides
-an <code>if</code>, <code>elif</code>, <code>else</code>,
-<code>endif</code> structure for building conditional statements. This
-allows you to effectively generate multiple logical pages out of one
-actual page.</p>
+ <p>Now that we have variables, and are able to set and compare
+ their values, we can use them to express conditionals. This
+ lets SSI be a tiny programming language of sorts.
+ <code>mod_include</code> provides an <code>if</code>,
+ <code>elif</code>, <code>else</code>, <code>endif</code>
+ structure for building conditional statements. This allows you
+ to effectively generate multiple logical pages out of one
+ actual page.</p>
-<p>The structure of this conditional construct is:</p>
-
+ <p>The structure of this conditional construct is:</p>
<pre>
<!--#if expr="test_condition" -->
<!--#elif expr="test_condition" -->
<!--#else -->
<!--#endif -->
</pre>
-
-<p>A <em>test_condition</em> can be any sort of logical comparison -
-either comparing values to one another, or testing the ``truth'' of a
-particular value. (A given string is true if it is nonempty.) For a
-full list of the comparison operators available to you, see the
-<code>mod_include</code> documentation. Here are some examples of how
-one might use this construct.</p>
-<p>In your configuration file, you could put the following line:</p>
+ <p>A <em>test_condition</em> can be any sort of logical
+ comparison - either comparing values to one another, or testing
+ the ``truth'' of a particular value. (A given string is true if
+ it is nonempty.) For a full list of the comparison operators
+ available to you, see the <code>mod_include</code>
+ documentation. Here are some examples of how one might use this
+ construct.</p>
+ <p>In your configuration file, you could put the following
+ line:</p>
<pre>
BrowserMatchNoCase macintosh Mac
BrowserMatchNoCase MSIE InternetExplorer
</pre>
-
-<p>This will set environment variables ``Mac'' and ``InternetExplorer''
-to true, if the client is running Internet Explorer on a Macintosh.</p>
-<p>Then, in your SSI-enabled document, you might do the following:</p>
+ <p>This will set environment variables ``Mac'' and
+ ``InternetExplorer'' to true, if the client is running Internet
+ Explorer on a Macintosh.</p>
+ <p>Then, in your SSI-enabled document, you might do the
+ following:</p>
<pre>
<!--#if expr="${Mac} && ${InternetExplorer}" -->
Apologetic text goes here
@@ -495,25 +524,25 @@
<!--#endif -->
</pre>
-<p>Not that I have anything against IE on Macs - I just struggled for a
-few hours last week trying to get some JavaScript working on IE on a
-Mac, when it was working everywhere else. The above was the interim
-workaround.</p>
-
-<p>Any other variable (either ones that you define, or normal
-environment variables) can be used in conditional statements. With
-Apache's ability to set environment variables with the
-<code>SetEnvIf</code> directives, and other related directives, this
-functionality can let you do some pretty involved dynamic stuff without
-ever resorting to CGI.</p>
-
-<hr>
-<h2><a name="conclusion">Conclusion</a></h2>
-
-<p>SSI is certainly not a replacement for CGI, or other technologies
-used for generating dynamic web pages. But it is a great way to add
-small amounts of dynamic content to pages, without doing a lot of extra
-work.</p>
-</body>
+ <p>Not that I have anything against IE on Macs - I just
+ struggled for a few hours last week trying to get some
+ JavaScript working on IE on a Mac, when it was working
+ everywhere else. The above was the interim workaround.</p>
+
+ <p>Any other variable (either ones that you define, or normal
+ environment variables) can be used in conditional statements.
+ With Apache's ability to set environment variables with the
+ <code>SetEnvIf</code> directives, and other related directives,
+ this functionality can let you do some pretty involved dynamic
+ stuff without ever resorting to CGI.</p>
+ <hr />
+
+ <h2><a id="conclusion" name="conclusion">Conclusion</a></h2>
+
+ <p>SSI is certainly not a replacement for CGI, or other
+ technologies used for generating dynamic web pages. But it is a
+ great way to add small amounts of dynamic content to pages,
+ without doing a lot of extra work.</p>
+ </body>
</html>
1.2 +3 -0 httpd-docs-1.3/htdocs/manual/howto/ssi.html.html
Index: ssi.html.html
===================================================================
RCS file: /home/cvs/httpd-docs-1.3/htdocs/manual/howto/ssi.html.html,v
retrieving revision 1.1
retrieving revision 1.2
diff -u -r1.1 -r1.2
--- ssi.html.html 2001/02/16 02:55:26 1.1
+++ ssi.html.html 2001/10/08 01:23:28 1.2
@@ -1 +1,4 @@
+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
+ "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd";>
<!--#include virtual="ssi.html.en" -->
+
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