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| author |   hongbotian <hongbo.tianhongbo@huawei.com> | 2015-11-30 03:10:21 -0500 |
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| committer | hongbotian <hongbo.tianhongbo@huawei.com> | 2015-11-30 03:10:21 -0500 |
| commit | c0b7206652b2852bc574694e7ba07ba1c2acdc00 (patch) | |
| tree | 5cb95cb0e19e03610525903df46279df2c3b7eb1 /rubbos/app/httpd-2.0.64/docs/manual/env.html.en | |
| parent | b6d3d6e668b793220f2d3af1bc3e828553dc3fe6 (diff) | |
delete app
Change-Id: Id4c572809969ebe89e946e88063eaed262cff3f2
Signed-off-by: hongbotian <hongbo.tianhongbo@huawei.com>
Diffstat (limited to 'rubbos/app/httpd-2.0.64/docs/manual/env.html.en')
| -rw-r--r-- | rubbos/app/httpd-2.0.64/docs/manual/env.html.en | 417 |
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diff --git a/rubbos/app/httpd-2.0.64/docs/manual/env.html.en b/rubbos/app/httpd-2.0.64/docs/manual/env.html.en deleted file mode 100644 index b1713321..00000000 --- a/rubbos/app/httpd-2.0.64/docs/manual/env.html.en +++ /dev/null @@ -1,417 +0,0 @@ -<?xml version="1.0" encoding="ISO-8859-1"?> -<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> -<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head><!-- - XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX - This file is generated from xml source: DO NOT EDIT - XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX - --> -<title>Environment Variables in Apache - Apache HTTP Server</title> -<link href="./style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" /> -<link href="./style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" /> -<link href="./style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" /> -<link href="./images/favicon.ico" rel="shortcut icon" /></head> -<body id="manual-page"><div id="page-header"> -<p class="menu"><a href="./mod/">Modules</a> | <a href="./mod/directives.html">Directives</a> | <a href="./faq/">FAQ</a> | <a href="./glossary.html">Glossary</a> | <a href="./sitemap.html">Sitemap</a></p> -<p class="apache">Apache HTTP Server Version 2.0</p> -<img alt="" src="./images/feather.gif" /></div> -<div class="up"><a href="./"><img title="<-" alt="<-" src="./images/left.gif" /></a></div> -<div id="path"> -<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 2.0</a></div><div id="page-content"><div id="preamble"><h1>Environment Variables in Apache</h1> -<div class="toplang"> -<p><span>Available Languages: </span><a href="./en/env.html" title="English"> en </a> | -<a href="./es/env.html" hreflang="es" rel="alternate" title="Español"> es </a> | -<a href="./fr/env.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | -<a href="./ja/env.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | -<a href="./ko/env.html" hreflang="ko" rel="alternate" title="Korean"> ko </a> | -<a href="./tr/env.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p> -</div> - - <p>The Apache HTTP Server provides a mechanism for storing - information in named variables that are called <em>environment - variables</em>. This information can be used to control various - operations such as logging or access control. The variables are - also used as a mechanism to communicate with external programs - such as CGI scripts. This document discusses different ways to - manipulate and use these variables.</p> - - <p>Although these variables are referred to as <em>environment - variables</em>, they are not the same as the environment - variables controlled by the underlying operating system. - Instead, these variables are stored and manipulated in an - internal Apache structure. They only become actual operating - system environment variables when they are provided to CGI - scripts and Server Side Include scripts. If you wish to - manipulate the operating system environment under which the - server itself runs, you must use the standard environment - manipulation mechanisms provided by your operating system - shell.</p> - </div> -<div id="quickview"><ul id="toc"><li><img alt="" src="./images/down.gif" /> <a href="#setting">Setting Environment Variables</a></li> -<li><img alt="" src="./images/down.gif" /> <a href="#using">Using Environment Variables</a></li> -<li><img alt="" src="./images/down.gif" /> <a href="#special">Special Purpose Environment Variables</a></li> -<li><img alt="" src="./images/down.gif" /> <a href="#examples">Examples</a></li> -</ul></div> -<div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> -<div class="section"> -<h2><a name="setting" id="setting">Setting Environment Variables</a></h2> - - <table class="related"><tr><th>Related Modules</th><th>Related Directives</th></tr><tr><td><ul><li><code class="module"><a href="./mod/mod_env.html">mod_env</a></code></li><li><code class="module"><a href="./mod/mod_rewrite.html">mod_rewrite</a></code></li><li><code class="module"><a href="./mod/mod_setenvif.html">mod_setenvif</a></code></li><li><code class="module"><a href="./mod/mod_unique_id.html">mod_unique_id</a></code></li></ul></td><td><ul><li><code class="directive"><a href="./mod/mod_setenvif.html#browsermatch">BrowserMatch</a></code></li><li><code class="directive"><a href="./mod/mod_setenvif.html#browsermatchnocase">BrowserMatchNoCase</a></code></li><li><code class="directive"><a href="./mod/mod_env.html#passenv">PassEnv</a></code></li><li><code class="directive"><a href="./mod/mod_rewrite.html#rewriterule">RewriteRule</a></code></li><li><code class="directive"><a href="./mod/mod_env.html#setenv">SetEnv</a></code></li><li><code class="directive"><a href="./mod/mod_setenvif.html#setenvif">SetEnvIf</a></code></li><li><code class="directive"><a href="./mod/mod_setenvif.html#setenvifnocase">SetEnvIfNoCase</a></code></li><li><code class="directive"><a href="./mod/mod_env.html#unsetenv">UnsetEnv</a></code></li></ul></td></tr></table> - - <h3><a name="basic-manipulation" id="basic-manipulation">Basic Environment Manipulation</a></h3> - - - <p>The most basic way to set an environment variable in Apache - is using the unconditional <code class="directive"><a href="./mod/mod_env.html#setenv">SetEnv</a></code> directive. Variables may also be passed from - the environment of the shell which started the server using the - <code class="directive"><a href="./mod/mod_env.html#passenv">PassEnv</a></code> directive.</p> - - - <h3><a name="conditional" id="conditional">Conditional Per-Request Settings</a></h3> - - - <p>For additional flexibility, the directives provided by - <code class="module"><a href="./mod/mod_setenvif.html">mod_setenvif</a></code> allow environment variables to be set - on a per-request basis, conditional on characteristics of particular - requests. For example, a variable could be set only when a - specific browser (User-Agent) is making a request, or only when - a specific Referer [sic] header is found. Even more flexibility - is available through the <code class="module"><a href="./mod/mod_rewrite.html">mod_rewrite</a></code>'s <code class="directive"><a href="./mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> which uses the - <code>[E=...]</code> option to set environment variables.</p> - - - <h3><a name="unique-identifiers" id="unique-identifiers">Unique Identifiers</a></h3> - - - <p>Finally, <code class="module"><a href="./mod/mod_unique_id.html">mod_unique_id</a></code> sets the environment variable <code>UNIQUE_ID</code> for each request to a value which is - guaranteed to be unique across "all" requests under very - specific conditions.</p> - - - <h3><a name="standard-cgi" id="standard-cgi">Standard CGI Variables</a></h3> - - - <p>In addition to all environment variables set within the - Apache configuration and passed from the shell, CGI scripts and - SSI pages are provided with a set of environment variables - containing meta-information about the request as required by - the <a href="http://cgi-spec.golux.com/">CGI - specification</a>.</p> - - - <h3><a name="caveats" id="caveats">Some Caveats</a></h3> - - - <ul> - <li>It is not possible to override or change the standard CGI - variables using the environment manipulation directives.</li> - - <li>When <code class="program"><a href="./programs/suexec.html">suexec</a></code> is used to launch - CGI scripts, the environment will be cleaned down to a set of - <em>safe</em> variables before CGI scripts are launched. The - list of <em>safe</em> variables is defined at compile-time in - <code>suexec.c</code>.</li> - - <li>For portability reasons, the names of environment - variables may contain only letters, numbers, and the - underscore character. In addition, the first character may - not be a number. Characters which do not match this - restriction will be replaced by an underscore when passed to - CGI scripts and SSI pages.</li> - - <li>The <code class="directive"><a href="./mod/mod_env.html#setenv">SetEnv</a></code> directive runs - late during request processing meaning that directives such as - <code class="directive"><a href="./mod/mod_setenvif.html#setenvif">SetEnvIf</a></code> and <code class="directive"><a href="./mod/mod_rewrite.html#rewritecond">RewriteCond</a></code> will not see the - variables set with it.</li> - </ul> - - </div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> -<div class="section"> -<h2><a name="using" id="using">Using Environment Variables</a></h2> - - - <table class="related"><tr><th>Related Modules</th><th>Related Directives</th></tr><tr><td><ul><li><code class="module"><a href="./mod/mod_access.html">mod_access</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_ext_filter.html">mod_ext_filter</a></code></li><li><code class="module"><a href="./mod/mod_headers.html">mod_headers</a></code></li><li><code class="module"><a href="./mod/mod_include.html">mod_include</a></code></li><li><code class="module"><a href="./mod/mod_log_config.html">mod_log_config</a></code></li><li><code class="module"><a href="./mod/mod_rewrite.html">mod_rewrite</a></code></li></ul></td><td><ul><li><code class="directive"><a href="./mod/mod_access.html#allow">Allow</a></code></li><li><code class="directive"><a href="./mod/mod_log_config.html#customlog">CustomLog</a></code></li><li><code class="directive"><a href="./mod/mod_access.html#deny">Deny</a></code></li><li><code class="directive"><a href="./mod/mod_ext_filter.html#extfilterdefine">ExtFilterDefine</a></code></li><li><code class="directive"><a href="./mod/mod_headers.html#header">Header</a></code></li><li><code class="directive"><a href="./mod/mod_log_config.html#logformat">LogFormat</a></code></li><li><code class="directive"><a href="./mod/mod_rewrite.html#rewritecond">RewriteCond</a></code></li><li><code class="directive"><a href="./mod/mod_rewrite.html#rewriterule">RewriteRule</a></code></li></ul></td></tr></table> - - <h3><a name="cgi-scripts" id="cgi-scripts">CGI Scripts</a></h3> - - - <p>One of the primary uses of environment variables is to - communicate information to CGI scripts. As discussed above, the - environment passed to CGI scripts includes standard - meta-information about the request in addition to any variables - set within the Apache configuration. For more details, see the - <a href="howto/cgi.html">CGI tutorial</a>.</p> - - - <h3><a name="ssi-pages" id="ssi-pages">SSI Pages</a></h3> - - - <p>Server-parsed (SSI) documents processed by <code class="module"><a href="./mod/mod_include.html">mod_include</a></code>'s - <code>INCLUDES</code> filter can print environment variables - using the <code>echo</code> element, and can use environment - variables in flow control elements to makes parts of a page - conditional on characteristics of a request. Apache also - provides SSI pages with the standard CGI environment variables - as discussed above. For more details, see the <a href="howto/ssi.html">SSI tutorial</a>.</p> - - - <h3><a name="access-control" id="access-control">Access Control</a></h3> - - - <p>Access to the server can be controlled based on the value of - environment variables using the <code>allow from env=</code> - and <code>deny from env=</code> directives. In combination with - <code class="directive"><a href="./mod/mod_setenvif.html#setenvif">SetEnvIf</a></code>, this - allows for flexible control of access to the server based on - characteristics of the client. For example, you can use these - directives to deny access to a particular browser (User-Agent). - </p> - - - <h3><a name="logging" id="logging">Conditional Logging</a></h3> - - - <p>Environment variables can be logged in the access log using - the <code class="directive"><a href="./mod/mod_log_config.html#logformat">LogFormat</a></code> - option <code>%e</code>. In addition, the decision on whether - or not to log requests can be made based on the status of - environment variables using the conditional form of the - <code class="directive"><a href="./mod/mod_log_config.html#customlog">CustomLog</a></code> - directive. In combination with <code class="directive"><a href="./mod/mod_setenvif.html#setenvif">SetEnvIf</a></code> this allows for flexible control of which - requests are logged. For example, you can choose not to log - requests for filenames ending in <code>gif</code>, or you can - choose to only log requests from clients which are outside your - subnet.</p> - - - <h3><a name="response-headers" id="response-headers">Conditional Response Headers</a></h3> - - - <p>The <code class="directive"><a href="./mod/mod_headers.html#header">Header</a></code> - directive can use the presence or - absence of an environment variable to determine whether or not - a certain HTTP header will be placed in the response to the - client. This allows, for example, a certain response header to - be sent only if a corresponding header is received in the - request from the client.</p> - - - - <h3><a name="external-filter" id="external-filter">External Filter Activation</a></h3> - - - <p>External filters configured by <code class="module"><a href="./mod/mod_ext_filter.html">mod_ext_filter</a></code> - using the <code class="directive"><a href="./mod/mod_ext_filter.html#extfilterdefine">ExtFilterDefine</a></code> directive can - by activated conditional on an environment variable using the - <code>disableenv=</code> and <code>enableenv=</code> options.</p> - - - <h3><a name="url-rewriting" id="url-rewriting">URL Rewriting</a></h3> - - - <p>The <code>%{ENV:<em>variable</em>}</code> form of - <em>TestString</em> in the <code class="directive"><a href="./mod/mod_rewrite.html#rewritecond">RewriteCond</a></code> allows <code class="module"><a href="./mod/mod_rewrite.html">mod_rewrite</a></code>'s rewrite - engine to make decisions conditional on environment variables. - Note that the variables accessible in <code class="module"><a href="./mod/mod_rewrite.html">mod_rewrite</a></code> - without the <code>ENV:</code> prefix are not actually environment - variables. Rather, they are variables special to - <code class="module"><a href="./mod/mod_rewrite.html">mod_rewrite</a></code> which cannot be accessed from other - modules.</p> - - </div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> -<div class="section"> -<h2><a name="special" id="special">Special Purpose Environment Variables</a></h2> - - - <p>Interoperability problems have led to the introduction of - mechanisms to modify the way Apache behaves when talking to - particular clients. To make these mechanisms as flexible as - possible, they are invoked by defining environment variables, - typically with <code class="directive"><a href="./mod/mod_setenvif.html#browsermatch">BrowserMatch</a></code>, - though <code class="directive"><a href="./mod/mod_env.html#setenv">SetEnv</a></code> and - <code class="directive"><a href="./mod/mod_env.html#passenv">PassEnv</a></code> could also be used, - for example.</p> - - <h3><a name="downgrade" id="downgrade">downgrade-1.0</a></h3> - - - <p>This forces the request to be treated as a HTTP/1.0 request - even if it was in a later dialect.</p> - - - <h3><a name="force-no-vary" id="force-no-vary">force-no-vary</a></h3> - - - <p>This causes any <code>Vary</code> fields to be removed from - the response header before it is sent back to the client. Some - clients don't interpret this field correctly (see the <a href="misc/known_client_problems.html">known client - problems</a> page); setting this variable can work around this - problem. Setting this variable also implies - <strong>force-response-1.0</strong>.</p> - - - <h3><a name="force-response" id="force-response">force-response-1.0</a></h3> - - - <p>This forces an HTTP/1.0 response to clients making an HTTP/1.0 - request. It was originally - implemented as a result of a problem with AOL's proxies. Some - HTTP/1.0 clients may not behave correctly when given an HTTP/1.1 - response, and this can be used to interoperate with them.</p> - - - - <h3><a name="gzip-only-text-html" id="gzip-only-text-html">gzip-only-text/html</a></h3> - - - <p>When set to a value of "1", this variable disables the - <code>DEFLATE</code> output filter provided by - <code class="module"><a href="./mod/mod_deflate.html">mod_deflate</a></code> for content-types other than - <code>text/html</code>.</p> - - - <h3><a name="no-gzip" id="no-gzip">no-gzip</a></h3> - - <p>When set, the <code>DEFLATE</code> filter of - <code class="module"><a href="./mod/mod_deflate.html">mod_deflate</a></code> will be turned off.</p> - - - - <h3><a name="nokeepalive" id="nokeepalive">nokeepalive</a></h3> - - - <p>This disables <code class="directive"><a href="./mod/core.html#keepalive">KeepAlive</a></code> - when set.</p> - - - - <h3><a name="prefer-language" id="prefer-language">prefer-language</a></h3> - - <p>This influences <code class="module"><a href="./mod/mod_negotiation.html">mod_negotiation</a></code>'s behaviour. If - it contains a language tag (such as <code>en</code>, <code>ja</code> - or <code>x-klingon</code>), <code class="module"><a href="./mod/mod_negotiation.html">mod_negotiation</a></code> tries - to deliver a variant with that language. If there's no such variant, - the normal <a href="content-negotiation.html">negotiation</a> process - applies.</p> - - - - <h3><a name="redirect-carefully" id="redirect-carefully">redirect-carefully</a></h3> - - - <p>This forces the server to be more careful when sending a redirect - to the client. This is typically used when a client has a known - problem handling redirects. This was originally implemented as a - result of a problem with Microsoft's WebFolders software which has - a problem handling redirects on directory resources via DAV - methods.</p> - - - - <h3><a name="suppress-error-charset" id="suppress-error-charset">suppress-error-charset</a></h3> - - - <p><em>Available in versions after 2.0.54</em></p> - - <p>When Apache issues a redirect in response to a client request, - the response includes some actual text to be displayed in case - the client can't (or doesn't) automatically follow the redirection. - Apache ordinarily labels this text according to the character set - which it uses, which is ISO-8859-1.</p> - - <p> However, if the redirection is to a page that uses a different - character set, some broken browser versions will try to use the - character set from the redirection text rather than the actual page. - This can result in Greek, for instance, being incorrectly rendered.</p> - - <p>Setting this environment variable causes Apache to omit the character - set for the redirection text, and these broken browsers will then correctly - use that of the destination page.</p> - - - - </div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> -<div class="section"> -<h2><a name="examples" id="examples">Examples</a></h2> - - - <h3><a name="misbehaving" id="misbehaving">Changing protocol behavior with misbehaving clients</a></h3> - - - <p>We recommend that the following lines be included in - httpd.conf to deal with known client problems.</p> -<div class="example"><pre> -# -# The following directives modify normal HTTP response behavior. -# The first directive disables keepalive for Netscape 2.x and browsers that -# spoof it. There are known problems with these browser implementations. -# The second directive is for Microsoft Internet Explorer 4.0b2 -# which has a broken HTTP/1.1 implementation and does not properly -# support keepalive when it is used on 301 or 302 (redirect) responses. -# -BrowserMatch "Mozilla/2" nokeepalive -BrowserMatch "MSIE 4\.0b2;" nokeepalive downgrade-1.0 force-response-1.0 - -# -# The following directive disables HTTP/1.1 responses to browsers which -# are in violation of the HTTP/1.0 spec by not being able to grok a -# basic 1.1 response. -# -BrowserMatch "RealPlayer 4\.0" force-response-1.0 -BrowserMatch "Java/1\.0" force-response-1.0 -BrowserMatch "JDK/1\.0" force-response-1.0</pre></div> - - - <h3><a name="no-img-log" id="no-img-log">Do not log requests for images in the access log</a></h3> - - - <p>This example keeps requests for images from appearing in the - access log. It can be easily modified to prevent logging of - particular directories, or to prevent logging of requests - coming from particular hosts.</p> - - <div class="example"><p><code> - SetEnvIf Request_URI \.gif image-request<br /> - SetEnvIf Request_URI \.jpg image-request<br /> - SetEnvIf Request_URI \.png image-request<br /> - CustomLog logs/access_log common env=!image-request - </code></p></div> - - - <h3><a name="image-theft" id="image-theft">Prevent "Image Theft"</a></h3> - - - <p>This example shows how to keep people not on your server - from using images on your server as inline-images on their - pages. This is not a recommended configuration, but it can work - in limited circumstances. We assume that all your images are in - a directory called /web/images.</p> - - <div class="example"><p><code> - SetEnvIf Referer "^http://www\.example\.com/" local_referal<br /> - # Allow browsers that do not send Referer info<br /> - SetEnvIf Referer "^$" local_referal<br /> - <Directory /web/images><br /> - <span class="indent"> - Order Deny,Allow<br /> - Deny from all<br /> - Allow from env=local_referal - </span> - </Directory> - </code></p></div> - - <p>For more information about this technique, see the - "<a href="http://www.serverwatch.com/tutorials/article.php/1132731">Keeping Your Images from Adorning Other Sites</a>" tutorial on - ServerWatch.</p> - - </div></div> -<div class="bottomlang"> -<p><span>Available Languages: </span><a href="./en/env.html" title="English"> en </a> | -<a href="./es/env.html" hreflang="es" rel="alternate" title="Español"> es </a> | -<a href="./fr/env.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | -<a href="./ja/env.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | -<a href="./ko/env.html" hreflang="ko" rel="alternate" title="Korean"> ko </a> | -<a href="./tr/env.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p> -</div><div id="footer"> -<p class="apache">Copyright 2009 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p> -<p class="menu"><a href="./mod/">Modules</a> | <a href="./mod/directives.html">Directives</a> | <a href="./faq/">FAQ</a> | <a href="./glossary.html">Glossary</a> | <a href="./sitemap.html">Sitemap</a></p></div> -</body></html>
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