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601 lines
31 KiB
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601 lines
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<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
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<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head>
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<meta content="text/html; charset=UTF-8" http-equiv="Content-Type" />
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<!--
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This file is generated from xml source: DO NOT EDIT
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-->
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<title>Apache Tutorial: Dynamic Content with CGI - Apache HTTP Server Version 2.5</title>
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<link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" />
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<link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" />
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<link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" /><link rel="stylesheet" type="text/css" href="../style/css/prettify.css" />
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<script src="../style/scripts/prettify.min.js" type="text/javascript">
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</script>
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<link href="../images/favicon.ico" rel="shortcut icon" /></head>
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<body id="manual-page"><div id="page-header">
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<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/quickreference.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p>
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<p class="apache">Apache HTTP Server Version 2.5</p>
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<img alt="" src="../images/feather.png" /></div>
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<div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div>
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<div id="path">
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<a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="../">Version 2.5</a> > <a href="./">How-To / Tutorials</a></div><div id="page-content"><div id="preamble"><h1>Apache Tutorial: Dynamic Content with CGI</h1>
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<div class="toplang">
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<p><span>Available Languages: </span><a href="../en/howto/cgi.html" title="English"> en </a> |
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<a href="../es/howto/cgi.html" hreflang="es" rel="alternate" title="Español"> es </a> |
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<a href="../fr/howto/cgi.html" hreflang="fr" rel="alternate" title="Français"> fr </a> |
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<a href="../ja/howto/cgi.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> |
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<a href="../ko/howto/cgi.html" hreflang="ko" rel="alternate" title="Korean"> ko </a></p>
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</div>
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</div>
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<div id="quickview"><ul id="toc"><li><img alt="" src="../images/down.gif" /> <a href="#intro">Introduction</a></li>
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<li><img alt="" src="../images/down.gif" /> <a href="#configuring">Configuring Apache to permit CGI</a></li>
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<li><img alt="" src="../images/down.gif" /> <a href="#writing">Writing a CGI program</a></li>
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<li><img alt="" src="../images/down.gif" /> <a href="#troubleshoot">But it's still not working!</a></li>
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<li><img alt="" src="../images/down.gif" /> <a href="#behindscenes">What's going on behind the scenes?</a></li>
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<li><img alt="" src="../images/down.gif" /> <a href="#libraries">CGI modules/libraries</a></li>
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<li><img alt="" src="../images/down.gif" /> <a href="#moreinfo">For more information</a></li>
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</ul><h3>See also</h3><ul class="seealso"><li><a href="#comments_section">Comments</a></li></ul></div>
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<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
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<div class="section">
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<h2><a name="intro" id="intro">Introduction</a> <a title="Permanent link" href="#intro" class="permalink">¶</a></h2>
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<table class="related"><tr><th>Related Modules</th><th>Related Directives</th></tr><tr><td><ul><li><code class="module"><a href="../mod/mod_alias.html">mod_alias</a></code></li><li><code class="module"><a href="../mod/mod_cgi.html">mod_cgi</a></code></li><li><code class="module"><a href="../mod/mod_cgid.html">mod_cgid</a></code></li></ul></td><td><ul><li><code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code></li><li><code class="directive"><a href="../mod/core.html#options">Options</a></code></li><li><code class="directive"><a href="../mod/mod_alias.html#scriptalias">ScriptAlias</a></code></li></ul></td></tr></table>
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<p>The CGI (Common Gateway Interface) defines a way for a web
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server to interact with external content-generating programs,
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which are often referred to as CGI programs or CGI scripts. It
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is a simple way to put dynamic content on
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your web site, using whatever programming language you're most
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familiar with. This document will be an introduction to setting
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up CGI on your Apache web server, and getting started writing
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CGI programs.</p>
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</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
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<div class="section">
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<h2><a name="configuring" id="configuring">Configuring Apache to permit CGI</a> <a title="Permanent link" href="#configuring" class="permalink">¶</a></h2>
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<p>In order to get your CGI programs to work properly, you'll
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need to have Apache configured to permit CGI execution. There
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are several ways to do this.</p>
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<div class="warning">Note: If Apache has been built with shared module
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support you need to ensure that the module is loaded; in your
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<code>httpd.conf</code> you need to make sure the
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<code class="directive"><a href="../mod/mod_so.html#loadmodule">LoadModule</a></code>
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directive has not been commented out. A correctly configured directive
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may look like this:
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<pre class="prettyprint lang-config">LoadModule cgid_module modules/mod_cgid.so</pre>
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On Windows, or using a non-threaded MPM like prefork, A correctly
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configured directive may look like this:
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<pre class="prettyprint lang-config">LoadModule cgi_module modules/mod_cgi.so</pre>
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</div>
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<h3><a name="scriptalias" id="scriptalias">ScriptAlias</a></h3>
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<p>The
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<code class="directive"><a href="../mod/mod_alias.html#scriptalias">ScriptAlias</a></code>
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directive tells Apache that a particular directory is set
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aside for CGI programs. Apache will assume that every file in
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this directory is a CGI program, and will attempt to execute
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it, when that particular resource is requested by a
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client.</p>
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<p>The <code class="directive"><a href="../mod/mod_alias.html#scriptalias">ScriptAlias</a></code>
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directive looks like:</p>
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<pre class="prettyprint lang-config">ScriptAlias "/cgi-bin/" "/usr/local/apache2/cgi-bin/"</pre>
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<p>The example shown is from your default <code>httpd.conf</code>
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configuration file, if you installed Apache in the default
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location. The <code class="directive"><a href="../mod/mod_alias.html#scriptalias">ScriptAlias</a></code>
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directive is much like the <code class="directive"><a href="../mod/mod_alias.html#alias">Alias</a></code> directive, which defines a URL prefix that
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is to mapped to a particular directory. <code class="directive">Alias</code>
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and <code class="directive">ScriptAlias</code> are usually used for
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directories that are outside of the <code class="directive"><a href="../mod/core.html#documentroot">DocumentRoot</a></code> directory. The difference between
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<code class="directive">Alias</code> and <code class="directive">ScriptAlias</code>
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is that <code class="directive">ScriptAlias</code> has the added meaning
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that everything under that URL prefix will be considered a CGI
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program. So, the example above tells Apache that any request for a
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resource beginning with <code>/cgi-bin/</code> should be served from
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the directory <code>/usr/local/apache2/cgi-bin/</code>, and should be
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treated as a CGI program.</p>
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<p>For example, if the URL
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<code>http://www.example.com/cgi-bin/test.pl</code>
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is requested, Apache will attempt to execute the file
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<code>/usr/local/apache2/cgi-bin/test.pl</code>
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and return the output. Of course, the file will have to
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exist, and be executable, and return output in a particular
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way, or Apache will return an error message.</p>
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<h3><a name="nonscriptalias" id="nonscriptalias">CGI outside of ScriptAlias directories</a></h3>
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<p>CGI programs are often restricted to <code class="directive"><a href="../mod/mod_alias.html#scriptalias">ScriptAlias</a></code>'ed directories for security reasons.
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In this way, administrators can tightly control who is allowed to
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use CGI programs. However, if the proper security precautions are
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taken, there is no reason why CGI programs cannot be run from
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arbitrary directories. For example, you may wish to let users
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have web content in their home directories with the
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<code class="directive"><a href="../mod/mod_userdir.html#userdir">UserDir</a></code> directive.
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If they want to have their own CGI programs, but don't have access to
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the main <code>cgi-bin</code> directory, they will need to be able to
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run CGI programs elsewhere.</p>
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<p>There are two steps to allowing CGI execution in an arbitrary
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directory. First, the <code>cgi-script</code> handler must be
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activated using the <code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code> or <code class="directive"><a href="../mod/core.html#sethandler">SetHandler</a></code> directive. Second,
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<code>ExecCGI</code> must be specified in the <code class="directive"><a href="../mod/core.html#options">Options</a></code> directive.</p>
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<h3><a name="options" id="options">Explicitly using Options to permit CGI execution</a></h3>
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<p>You could explicitly use the <code class="directive"><a href="../mod/core.html#options">Options</a></code> directive, inside your main server configuration
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file, to specify that CGI execution was permitted in a particular
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directory:</p>
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<pre class="prettyprint lang-config"><Directory "/usr/local/apache2/htdocs/somedir">
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Options +ExecCGI
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</Directory></pre>
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<p>The above directive tells Apache to permit the execution
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of CGI files. You will also need to tell the server what
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files are CGI files. The following <code class="directive"><a href="../mod/mod_mime.html#addhandler">AddHandler</a></code> directive tells the server to treat all
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files with the <code>cgi</code> or <code>pl</code> extension as CGI
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programs:</p>
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<pre class="prettyprint lang-config">AddHandler cgi-script .cgi .pl</pre>
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<h3><a name="htaccess" id="htaccess">.htaccess files</a></h3>
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<p>The <a href="htaccess.html"><code>.htaccess</code> tutorial</a>
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shows how to activate CGI programs if you do not have
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access to <code>httpd.conf</code>.</p>
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<h3><a name="userdir" id="userdir">User Directories</a></h3>
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<p>To allow CGI program execution for any file ending in
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<code>.cgi</code> in users' directories, you can use the
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following configuration.</p>
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<pre class="prettyprint lang-config"><Directory "/home/*/public_html">
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Options +ExecCGI
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AddHandler cgi-script .cgi
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</Directory></pre>
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<p>If you wish designate a <code>cgi-bin</code> subdirectory of
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a user's directory where everything will be treated as a CGI
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program, you can use the following.</p>
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<pre class="prettyprint lang-config"><Directory "/home/*/public_html/cgi-bin">
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Options ExecCGI
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SetHandler cgi-script
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</Directory></pre>
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</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
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<div class="section">
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<h2><a name="writing" id="writing">Writing a CGI program</a> <a title="Permanent link" href="#writing" class="permalink">¶</a></h2>
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<p>There are two main differences between ``regular''
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programming, and CGI programming.</p>
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<p>First, all output from your CGI program must be preceded by
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a <a class="glossarylink" href="../glossary.html#mime-type" title="see glossary">MIME-type</a> header. This is HTTP header that tells the client
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what sort of content it is receiving. Most of the time, this
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will look like:</p>
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<div class="example"><p><code>
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Content-type: text/html
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</code></p></div>
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<p>Secondly, your output needs to be in HTML, or some other
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format that a browser will be able to display. Most of the
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time, this will be HTML, but occasionally you might write a CGI
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program that outputs a gif image, or other non-HTML
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content.</p>
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<p>Apart from those two things, writing a CGI program will look
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a lot like any other program that you might write.</p>
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<h3><a name="firstcgi" id="firstcgi">Your first CGI program</a></h3>
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<p>The following is an example CGI program that prints one
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line to your browser. Type in the following, save it to a
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file called <code>first.pl</code>, and put it in your
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<code>cgi-bin</code> directory.</p>
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<pre class="prettyprint lang-perl">#!/usr/bin/perl
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print "Content-type: text/html\n\n";
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print "Hello, World.";</pre>
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<p>Even if you are not familiar with Perl, you should be able
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to see what is happening here. The first line tells Apache
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(or whatever shell you happen to be running under) that this
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program can be executed by feeding the file to the
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interpreter found at the location <code>/usr/bin/perl</code>.
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The second line prints the content-type declaration we
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talked about, followed by two carriage-return newline pairs.
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This puts a blank line after the header, to indicate the end
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of the HTTP headers, and the beginning of the body. The third
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line prints the string "Hello, World.". And that's the end
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of it.</p>
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<p>If you open your favorite browser and tell it to get the
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address</p>
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<div class="example"><p><code>
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http://www.example.com/cgi-bin/first.pl
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</code></p></div>
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<p>or wherever you put your file, you will see the one line
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<code>Hello, World.</code> appear in your browser window.
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It's not very exciting, but once you get that working, you'll
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have a good chance of getting just about anything working.</p>
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</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
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<div class="section">
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<h2><a name="troubleshoot" id="troubleshoot">But it's still not working!</a> <a title="Permanent link" href="#troubleshoot" class="permalink">¶</a></h2>
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<p>There are four basic things that you may see in your browser
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when you try to access your CGI program from the web:</p>
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<dl>
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<dt>The output of your CGI program</dt>
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<dd>Great! That means everything worked fine. If the output is correct,
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but the browser is not processing it correctly, make sure you have the
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correct <code>Content-Type</code> set in your CGI program.</dd>
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<dt>The source code of your CGI program or a "POST Method Not
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Allowed" message</dt>
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<dd>That means that you have not properly configured Apache
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to process your CGI program. Reread the section on
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<a href="#configuring">configuring
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Apache</a> and try to find what you missed.</dd>
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<dt>A message starting with "Forbidden"</dt>
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<dd>That means that there is a permissions problem. Check the
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<a href="#errorlogs">Apache error log</a> and the section below on
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<a href="#permissions">file permissions</a>.</dd>
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<dt>A message saying "Internal Server Error"</dt>
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<dd>If you check the
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<a href="#errorlogs">Apache error log</a>, you will probably
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find that it says "Premature end of
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script headers", possibly along with an error message
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generated by your CGI program. In this case, you will want to
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check each of the below sections to see what might be
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preventing your CGI program from emitting the proper HTTP
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headers.</dd>
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</dl>
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<h3><a name="permissions" id="permissions">File permissions</a></h3>
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<p>Remember that the server does not run as you. That is,
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when the server starts up, it is running with the permissions
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of an unprivileged user - usually <code>nobody</code>, or
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<code>www</code> - and so it will need extra permissions to
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execute files that are owned by you. Usually, the way to give
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a file sufficient permissions to be executed by <code>nobody</code>
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is to give everyone execute permission on the file:</p>
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<div class="example"><p><code>
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chmod a+x first.pl
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</code></p></div>
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<p>Also, if your program reads from, or writes to, any other
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files, those files will need to have the correct permissions
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to permit this.</p>
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<h3><a name="pathinformation" id="pathinformation">Path information and environment</a></h3>
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<p>When you run a program from your command line, you have
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certain information that is passed to the shell without you
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thinking about it. For example, you have a <code>PATH</code>,
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which tells the shell where it can look for files that you
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reference.</p>
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<p>When a program runs through the web server as a CGI program,
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it may not have the same <code>PATH</code>. Any programs that you
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invoke in your CGI program (like <code>sendmail</code>, for
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example) will need to be specified by a full path, so that the
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shell can find them when it attempts to execute your CGI
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program.</p>
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<p>A common manifestation of this is the path to the script
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interpreter (often <code>perl</code>) indicated in the first
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line of your CGI program, which will look something like:</p>
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<pre class="prettyprint lang-perl">#!/usr/bin/perl</pre>
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<p>Make sure that this is in fact the path to the
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interpreter.</p>
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<div class="warning">
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When editing CGI scripts on Windows, end-of-line characters may be
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appended to the interpreter path. Ensure that files are then
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transferred to the server in ASCII mode. Failure to do so may
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result in "Command not found" warnings from the OS, due to the
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unrecognized end-of-line character being interpreted as a part of
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the interpreter filename.
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</div>
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<h3><a name="missingenv" id="missingenv">Missing environment variables</a></h3>
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<p>If your CGI program depends on non-standard <a href="#env">environment variables</a>, you will need to
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assure that those variables are passed by Apache.</p>
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<p>When you miss HTTP headers from the environment, make
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sure they are formatted according to
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<a href="http://tools.ietf.org/html/rfc2616">RFC 2616</a>,
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section 4.2: Header names must start with a letter,
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followed only by letters, numbers or hyphen. Any header
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violating this rule will be dropped silently.</p>
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<h3><a name="syntaxerrors" id="syntaxerrors">Program errors</a></h3>
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<p>Most of the time when a CGI program fails, it's because of
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a problem with the program itself. This is particularly true
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once you get the hang of this CGI stuff, and no longer make
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the above two mistakes. The first thing to do is to make
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sure that your program runs from the command line before
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testing it via the web server. For example, try:</p>
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<div class="example"><p><code>
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cd /usr/local/apache2/cgi-bin<br />
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./first.pl
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</code></p></div>
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|
|
<p>(Do not call the <code>perl</code> interpreter. The shell
|
|
and Apache should find the interpreter using the <a href="#pathinformation">path information</a> on the first line of
|
|
the script.)</p>
|
|
|
|
<p>The first thing you see written by your program should be
|
|
a set of HTTP headers, including the <code>Content-Type</code>,
|
|
followed by a blank line. If you see anything else, Apache will
|
|
return the <code>Premature end of script headers</code> error if
|
|
you try to run it through the server. See <a href="#writing">Writing a CGI program</a> above for more
|
|
details.</p>
|
|
|
|
|
|
<h3><a name="errorlogs" id="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>
|
|
|
|
|
|
<h3><a name="suexec" id="suexec">Suexec</a></h3>
|
|
|
|
|
|
<p>The <a href="../suexec.html">suexec</a> support 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 <code>Premature end of script headers</code>.</p>
|
|
|
|
<p>To check if you are using suexec, run <code>apachectl
|
|
-V</code> and check for the location of <code>SUEXEC_BIN</code>.
|
|
If Apache finds an <code class="program"><a href="../programs/suexec.html">suexec</a></code> binary there on startup,
|
|
suexec will be activated.</p>
|
|
|
|
<p>Unless you fully understand suexec, you should not be using it.
|
|
To disable suexec, simply remove (or rename) the <code class="program"><a href="../programs/suexec.html">suexec</a></code>
|
|
binary pointed to by <code>SUEXEC_BIN</code> and then restart the
|
|
server. If, after reading about <a href="../suexec.html">suexec</a>,
|
|
you still wish to use it, then run <code>suexec -V</code> to find
|
|
the location of the suexec log file, and use that log file to
|
|
find what policy you are violating.</p>
|
|
|
|
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
|
|
<div class="section">
|
|
<h2><a name="behindscenes" id="behindscenes">What's going on behind the scenes?</a> <a title="Permanent link" href="#behindscenes" class="permalink">¶</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="env" id="env">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 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://www.ietf.org/rfc/rfc3875">Common Gateway
|
|
Interface RFC</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 class="prettyprint lang-perl">#!/usr/bin/perl
|
|
use strict;
|
|
use warnings;
|
|
|
|
print "Content-type: text/html\n\n";
|
|
foreach my $key (keys %ENV) {
|
|
print "$key --> $ENV{$key}<br>";
|
|
}</pre>
|
|
|
|
|
|
|
|
<h3><a name="stdin" id="stdin">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>
|
|
|
|
<div class="example"><p><code>
|
|
name=Rich%20Bowen&city=Lexington&state=KY&sidekick=Squirrel%20Monkey
|
|
</code></p></div>
|
|
|
|
<p>You'll sometimes also see this type of string appended to
|
|
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>
|
|
|
|
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
|
|
<div class="section">
|
|
<h2><a name="libraries" id="libraries">CGI modules/libraries</a> <a title="Permanent link" href="#libraries" class="permalink">¶</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 <code>CGI.pm</code>. You might
|
|
also consider <code>CGI::Lite</code>, 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 <code>CGIC</code> library, from
|
|
<a href="https://web.mit.edu/wwwdev/www/cgic.html">https://web.mit.edu/wwwdev/www/cgic.html</a>.</p>
|
|
</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div>
|
|
<div class="section">
|
|
<h2><a name="moreinfo" id="moreinfo">For more information</a> <a title="Permanent link" href="#moreinfo" class="permalink">¶</a></h2>
|
|
|
|
|
|
<p>The current CGI specification is available in the
|
|
<a href="http://www.ietf.org/rfc/rfc3875">Common Gateway
|
|
Interface RFC</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>
|
|
</div></div>
|
|
<div class="bottomlang">
|
|
<p><span>Available Languages: </span><a href="../en/howto/cgi.html" title="English"> en </a> |
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<a href="../es/howto/cgi.html" hreflang="es" rel="alternate" title="Español"> es </a> |
|
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<a href="../fr/howto/cgi.html" hreflang="fr" rel="alternate" title="Français"> fr </a> |
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<a href="../ja/howto/cgi.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> |
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<a href="../ko/howto/cgi.html" hreflang="ko" rel="alternate" title="Korean"> ko </a></p>
|
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</div><div class="top"><a href="#page-header"><img src="../images/up.gif" alt="top" /></a></div><div class="section"><h2><a id="comments_section" name="comments_section">Comments</a></h2><div class="warning"><strong>Notice:</strong><br />This is not a Q&A section. Comments placed here should be pointed towards suggestions on improving the documentation or server, and may be removed by our moderators if they are either implemented or considered invalid/off-topic. Questions on how to manage the Apache HTTP Server should be directed at either our IRC channel, #httpd, on Freenode, or sent to our <a href="https://httpd.apache.org/lists.html">mailing lists</a>.</div>
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