github.com/krum110487/go-htaccess@v0.0.0-20240316004156-60641c8e7598/tests/data/apache_2_2_34/manual/env.html.en (about) 1 <?xml version="1.0" encoding="ISO-8859-1"?> 2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> 3 <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head> 4 <meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type" /> 5 <!-- 6 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX 7 This file is generated from xml source: DO NOT EDIT 8 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX 9 --> 10 <title>Environment Variables in Apache - Apache HTTP Server Version 2.2</title> 11 <link href="./style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" /> 12 <link href="./style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" /> 13 <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" /> 14 <script src="./style/scripts/prettify.min.js" type="text/javascript"> 15 </script> 16 17 <link href="./images/favicon.ico" rel="shortcut icon" /><link href="http://httpd.apache.org/docs/current/env.html" rel="canonical" /></head> 18 <body id="manual-page"><div id="page-header"> 19 <p class="menu"><a href="./mod/">Modules</a> | <a href="./mod/directives.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> 20 <p class="apache">Apache HTTP Server Version 2.2</p> 21 <img alt="" src="./images/feather.gif" /></div> 22 <div class="up"><a href="./"><img title="<-" alt="<-" src="./images/left.gif" /></a></div> 23 <div id="path"> 24 <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 2.2</a></div><div id="page-content"><div class="retired"><h4>Please note</h4> 25 <p> This document refers to a legacy release (<strong>2.2</strong>) of Apache httpd. The active release (<strong>2.4</strong>) is documented <a href="http://httpd.apache.org/docs/current">here</a>. If you have not already upgraded, please follow <a href="http://httpd.apache.org/docs/current/upgrading.html">this link</a> for more information.</p> 26 <p>You may follow <a href="http://httpd.apache.org/docs/current/env.html">this link</a> to go to the current version of this document.</p></div><div id="preamble"><h1>Environment Variables in Apache</h1> 27 <div class="toplang"> 28 <p><span>Available Languages: </span><a href="./en/env.html" title="English"> en </a> | 29 <a href="./ja/env.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | 30 <a href="./ko/env.html" hreflang="ko" rel="alternate" title="Korean"> ko </a> | 31 <a href="./tr/env.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p> 32 </div> 33 34 <p>The Apache HTTP Server provides a mechanism for storing 35 information in named variables that are called <em>environment 36 variables</em>. This information can be used to control various 37 operations such as logging or access control. The variables are 38 also used as a mechanism to communicate with external programs 39 such as CGI scripts. This document discusses different ways to 40 manipulate and use these variables.</p> 41 42 <p>Although these variables are referred to as <em>environment 43 variables</em>, they are not the same as the environment 44 variables controlled by the underlying operating system. 45 Instead, these variables are stored and manipulated in an 46 internal Apache structure. They only become actual operating 47 system environment variables when they are provided to CGI 48 scripts and Server Side Include scripts. If you wish to 49 manipulate the operating system environment under which the 50 server itself runs, you must use the standard environment 51 manipulation mechanisms provided by your operating system 52 shell.</p> 53 </div> 54 <div id="quickview"><ul id="toc"><li><img alt="" src="./images/down.gif" /> <a href="#setting">Setting Environment Variables</a></li> 55 <li><img alt="" src="./images/down.gif" /> <a href="#using">Using Environment Variables</a></li> 56 <li><img alt="" src="./images/down.gif" /> <a href="#special">Special Purpose Environment Variables</a></li> 57 <li><img alt="" src="./images/down.gif" /> <a href="#examples">Examples</a></li> 58 </ul><ul class="seealso"><li><a href="#comments_section">Comments</a></li></ul></div> 59 <div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> 60 <div class="section"> 61 <h2><a name="setting" id="setting">Setting Environment Variables</a></h2> 62 63 <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> 64 65 <h3><a name="basic-manipulation" id="basic-manipulation">Basic Environment Manipulation</a></h3> 66 67 68 <p>The most basic way to set an environment variable in Apache 69 is using the unconditional <code class="directive"><a href="./mod/mod_env.html#setenv">SetEnv</a></code> directive. Variables may also be passed from 70 the environment of the shell which started the server using the 71 <code class="directive"><a href="./mod/mod_env.html#passenv">PassEnv</a></code> directive.</p> 72 73 74 <h3><a name="conditional" id="conditional">Conditional Per-Request Settings</a></h3> 75 76 77 <p>For additional flexibility, the directives provided by 78 <code class="module"><a href="./mod/mod_setenvif.html">mod_setenvif</a></code> allow environment variables to be set 79 on a per-request basis, conditional on characteristics of particular 80 requests. For example, a variable could be set only when a 81 specific browser (User-Agent) is making a request, or only when 82 a specific Referer [sic] header is found. Even more flexibility 83 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 84 <code>[E=...]</code> option to set environment variables.</p> 85 86 87 <h3><a name="unique-identifiers" id="unique-identifiers">Unique Identifiers</a></h3> 88 89 90 <p>Finally, <code class="module"><a href="./mod/mod_unique_id.html">mod_unique_id</a></code> sets the environment 91 variable <code>UNIQUE_ID</code> for each request to a value which is 92 guaranteed to be unique across "all" requests under very 93 specific conditions.</p> 94 95 96 <h3><a name="standard-cgi" id="standard-cgi">Standard CGI Variables</a></h3> 97 98 99 <p>In addition to all environment variables set within the 100 Apache configuration and passed from the shell, CGI scripts and 101 SSI pages are provided with a set of environment variables 102 containing meta-information about the request as required by 103 the <a href="http://www.w3.org/CGI/">CGI 104 specification</a>.</p> 105 106 107 <h3><a name="caveats" id="caveats">Some Caveats</a></h3> 108 109 110 <ul> 111 <li>It is not possible to override or change the standard CGI 112 variables using the environment manipulation directives.</li> 113 114 <li>When <code class="program"><a href="./programs/suexec.html">suexec</a></code> is used to launch 115 CGI scripts, the environment will be cleaned down to a set of 116 <em>safe</em> variables before CGI scripts are launched. The 117 list of <em>safe</em> variables is defined at compile-time in 118 <code>suexec.c</code>.</li> 119 120 <li>For portability reasons, the names of environment 121 variables may contain only letters, numbers, and the 122 underscore character. In addition, the first character may 123 not be a number. Characters which do not match this 124 restriction will be replaced by an underscore when passed to 125 CGI scripts and SSI pages.</li> 126 127 <li>The <code class="directive"><a href="./mod/mod_env.html#setenv">SetEnv</a></code> directive runs 128 late during request processing meaning that directives such as 129 <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 130 variables set with it.</li> 131 </ul> 132 133 </div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> 134 <div class="section"> 135 <h2><a name="using" id="using">Using Environment Variables</a></h2> 136 137 138 <table class="related"><tr><th>Related Modules</th><th>Related Directives</th></tr><tr><td><ul><li><code class="module"><a href="./mod/mod_authz_host.html">mod_authz_host</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_authz_host.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_authz_host.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> 139 140 <h3><a name="cgi-scripts" id="cgi-scripts">CGI Scripts</a></h3> 141 142 143 <p>One of the primary uses of environment variables is to 144 communicate information to CGI scripts. As discussed above, the 145 environment passed to CGI scripts includes standard 146 meta-information about the request in addition to any variables 147 set within the Apache configuration. For more details, see the 148 <a href="howto/cgi.html">CGI tutorial</a>.</p> 149 150 151 <h3><a name="ssi-pages" id="ssi-pages">SSI Pages</a></h3> 152 153 154 <p>Server-parsed (SSI) documents processed by 155 <code class="module"><a href="./mod/mod_include.html">mod_include</a></code>'s 156 <code>INCLUDES</code> filter can print environment variables 157 using the <code>echo</code> element, and can use environment 158 variables in flow control elements to makes parts of a page 159 conditional on characteristics of a request. Apache also 160 provides SSI pages with the standard CGI environment variables 161 as discussed above. For more details, see the <a href="howto/ssi.html">SSI tutorial</a>.</p> 162 163 164 <h3><a name="access-control" id="access-control">Access Control</a></h3> 165 166 167 <p>Access to the server can be controlled based on the value of 168 environment variables using the <code>allow from env=</code> 169 and <code>deny from env=</code> directives. In combination with 170 <code class="directive"><a href="./mod/mod_setenvif.html#setenvif">SetEnvIf</a></code>, this 171 allows for flexible control of access to the server based on 172 characteristics of the client. For example, you can use these 173 directives to deny access to a particular browser (User-Agent). 174 </p> 175 176 177 <h3><a name="logging" id="logging">Conditional Logging</a></h3> 178 179 180 <p>Environment variables can be logged in the access log using 181 the <code class="directive"><a href="./mod/mod_log_config.html#logformat">LogFormat</a></code> 182 option <code>%e</code>. In addition, the decision on whether 183 or not to log requests can be made based on the status of 184 environment variables using the conditional form of the 185 <code class="directive"><a href="./mod/mod_log_config.html#customlog">CustomLog</a></code> 186 directive. In combination with <code class="directive"><a href="./mod/mod_setenvif.html#setenvif">SetEnvIf</a></code> this allows for flexible control of which 187 requests are logged. For example, you can choose not to log 188 requests for filenames ending in <code>gif</code>, or you can 189 choose to only log requests from clients which are outside your 190 subnet.</p> 191 192 193 <h3><a name="response-headers" id="response-headers">Conditional Response Headers</a></h3> 194 195 196 <p>The <code class="directive"><a href="./mod/mod_headers.html#header">Header</a></code> 197 directive can use the presence or 198 absence of an environment variable to determine whether or not 199 a certain HTTP header will be placed in the response to the 200 client. This allows, for example, a certain response header to 201 be sent only if a corresponding header is received in the 202 request from the client.</p> 203 204 205 206 <h3><a name="external-filter" id="external-filter">External Filter Activation</a></h3> 207 208 209 <p>External filters configured by <code class="module"><a href="./mod/mod_ext_filter.html">mod_ext_filter</a></code> 210 using the <code class="directive"><a href="./mod/mod_ext_filter.html#extfilterdefine">ExtFilterDefine</a></code> directive can 211 by activated conditional on an environment variable using the 212 <code>disableenv=</code> and <code>enableenv=</code> options.</p> 213 214 215 <h3><a name="url-rewriting" id="url-rewriting">URL Rewriting</a></h3> 216 217 218 <p>The <code>%{ENV:<em>variable</em>}</code> form of 219 <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 220 engine to make decisions conditional on environment variables. Note 221 that the variables accessible in <code class="module"><a href="./mod/mod_rewrite.html">mod_rewrite</a></code> without 222 the <code>ENV:</code> prefix are not actually environment variables. 223 Rather, they are variables special to <code class="module"><a href="./mod/mod_rewrite.html">mod_rewrite</a></code> 224 which cannot be accessed from other modules.</p> 225 226 </div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> 227 <div class="section"> 228 <h2><a name="special" id="special">Special Purpose Environment Variables</a></h2> 229 230 231 <p>Interoperability problems have led to the introduction of 232 mechanisms to modify the way Apache behaves when talking to 233 particular clients. To make these mechanisms as flexible as 234 possible, they are invoked by defining environment variables, 235 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> 236 237 <h3><a name="downgrade" id="downgrade">downgrade-1.0</a></h3> 238 239 240 <p>This forces the request to be treated as a HTTP/1.0 request 241 even if it was in a later dialect.</p> 242 243 244 <h3><a name="force-gzip" id="force-gzip">force-gzip</a></h3> 245 246 <p>If you have the <code>DEFLATE</code> filter activated, this 247 environment variable will ignore the accept-encoding setting of 248 your browser and will send compressed output unconditionally.</p> 249 250 <h3><a name="force-no-vary" id="force-no-vary">force-no-vary</a></h3> 251 252 253 <p>This causes any <code>Vary</code> fields to be removed from 254 the response header before it is sent back to the client. Some 255 clients don't interpret this field correctly; setting this 256 variable can work around this problem. Setting this variable 257 also implies <strong>force-response-1.0</strong>.</p> 258 259 260 <h3><a name="force-response" id="force-response">force-response-1.0</a></h3> 261 262 263 <p>This forces an HTTP/1.0 response to clients making an HTTP/1.0 264 request. It was originally 265 implemented as a result of a problem with AOL's proxies. Some 266 HTTP/1.0 clients may not behave correctly when given an HTTP/1.1 267 response, and this can be used to interoperate with them.</p> 268 269 270 271 <h3><a name="gzip-only-text-html" id="gzip-only-text-html">gzip-only-text/html</a></h3> 272 273 274 <p>When set to a value of "1", this variable disables the 275 <code>DEFLATE</code> output filter provided by 276 <code class="module"><a href="./mod/mod_deflate.html">mod_deflate</a></code> for content-types other than 277 <code>text/html</code>. If you'd rather 278 use statically compressed files, <code class="module"><a href="./mod/mod_negotiation.html">mod_negotiation</a></code> 279 evaluates the variable as well (not only for gzip, but for all 280 encodings that differ from "identity").</p> 281 282 283 <h3><a name="no-gzip" id="no-gzip">no-gzip</a></h3> 284 285 <p>When set, the <code>DEFLATE</code> filter of 286 <code class="module"><a href="./mod/mod_deflate.html">mod_deflate</a></code> will be turned off and 287 <code class="module"><a href="./mod/mod_negotiation.html">mod_negotiation</a></code> will refuse to deliver encoded 288 resources.</p> 289 290 291 292 <h3><a name="no-cache" id="no-cache">no-cache</a></h3> 293 <p><em>Available in versions 2.2.12 and later</em></p> 294 295 <p>When set, <code class="module"><a href="./mod/mod_cache.html">mod_cache</a></code> will not save an otherwise 296 cacheable response. This environment variable does not influence 297 whether a response already in the cache will be served for the current 298 request.</p> 299 300 301 302 <h3><a name="nokeepalive" id="nokeepalive">nokeepalive</a></h3> 303 304 305 <p>This disables <code class="directive"><a href="./mod/core.html#keepalive">KeepAlive</a></code> 306 when set.</p> 307 308 309 310 <h3><a name="prefer-language" id="prefer-language">prefer-language</a></h3> 311 312 <p>This influences <code class="module"><a href="./mod/mod_negotiation.html">mod_negotiation</a></code>'s behaviour. If 313 it contains a language tag (such as <code>en</code>, <code>ja</code> 314 or <code>x-klingon</code>), <code class="module"><a href="./mod/mod_negotiation.html">mod_negotiation</a></code> tries 315 to deliver a variant with that language. If there's no such variant, 316 the normal <a href="content-negotiation.html">negotiation</a> process 317 applies.</p> 318 319 320 321 <h3><a name="redirect-carefully" id="redirect-carefully">redirect-carefully</a></h3> 322 323 324 <p>This forces the server to be more careful when sending a redirect 325 to the client. This is typically used when a client has a known 326 problem handling redirects. This was originally implemented as a 327 result of a problem with Microsoft's WebFolders software which has 328 a problem handling redirects on directory resources via DAV 329 methods.</p> 330 331 332 333 <h3><a name="suppress-error-charset" id="suppress-error-charset">suppress-error-charset</a></h3> 334 335 336 <p><em>Available in versions after 2.0.54</em></p> 337 338 <p>When Apache issues a redirect in response to a client request, 339 the response includes some actual text to be displayed in case 340 the client can't (or doesn't) automatically follow the redirection. 341 Apache ordinarily labels this text according to the character set 342 which it uses, which is ISO-8859-1.</p> 343 344 <p> However, if the redirection is to a page that uses a different 345 character set, some broken browser versions will try to use the 346 character set from the redirection text rather than the actual page. 347 This can result in Greek, for instance, being incorrectly rendered.</p> 348 349 <p>Setting this environment variable causes Apache to omit the character 350 set for the redirection text, and these broken browsers will then correctly 351 use that of the destination page.</p> 352 353 <div class="warning"> 354 <h3>Security note</h3> 355 356 <p>Sending error pages without a specified character set may 357 allow a cross-site-scripting attack for existing browsers (MSIE) 358 which do not follow the HTTP/1.1 specification and attempt to 359 "guess" the character set from the content. Such browsers can 360 be easily fooled into using the UTF-7 character set, and UTF-7 361 content from input data (such as the request-URI) will not be 362 escaped by the usual escaping mechanisms designed to prevent 363 cross-site-scripting attacks.</p> 364 </div> 365 366 367 368 <h3><a name="proxy" id="proxy">force-proxy-request-1.0, proxy-nokeepalive, proxy-sendchunked, 369 proxy-sendcl, proxy-chain-auth, proxy-interim-response, proxy-initial-not-pooled</a></h3> 370 371 <p>These directives alter the protocol behavior of 372 <code class="module"><a href="./mod/mod_proxy.html">mod_proxy</a></code>. See the <code class="module"><a href="./mod/mod_proxy.html">mod_proxy</a></code> and <code class="module"><a href="./mod/mod_proxy_http.html">mod_proxy_http</a></code> 373 documentation for more details.</p> 374 375 376 </div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> 377 <div class="section"> 378 <h2><a name="examples" id="examples">Examples</a></h2> 379 380 381 <h3><a name="misbehaving" id="misbehaving">Changing protocol behavior with misbehaving clients</a></h3> 382 383 384 <p>Earlier versions recommended that the following lines be included in 385 httpd.conf to deal with known client problems. Since the affected clients 386 are no longer seen in the wild, this configuration is likely no-longer 387 necessary.</p> 388 <div class="example"><pre># 389 # The following directives modify normal HTTP response behavior. 390 # The first directive disables keepalive for Netscape 2.x and browsers that 391 # spoof it. There are known problems with these browser implementations. 392 # The second directive is for Microsoft Internet Explorer 4.0b2 393 # which has a broken HTTP/1.1 implementation and does not properly 394 # support keepalive when it is used on 301 or 302 (redirect) responses. 395 # 396 BrowserMatch "Mozilla/2" nokeepalive 397 BrowserMatch "MSIE 4\.0b2;" nokeepalive downgrade-1.0 force-response-1.0 398 399 # 400 # The following directive disables HTTP/1.1 responses to browsers which 401 # are in violation of the HTTP/1.0 spec by not being able to grok a 402 # basic 1.1 response. 403 # 404 BrowserMatch "RealPlayer 4\.0" force-response-1.0 405 BrowserMatch "Java/1\.0" force-response-1.0 406 BrowserMatch "JDK/1\.0" force-response-1.0</pre></div> 407 408 409 <h3><a name="no-img-log" id="no-img-log">Do not log requests for images in the access log</a></h3> 410 411 412 <p>This example keeps requests for images from appearing in the 413 access log. It can be easily modified to prevent logging of 414 particular directories, or to prevent logging of requests 415 coming from particular hosts.</p> 416 417 <div class="example"><p><code> 418 SetEnvIf Request_URI \.gif image-request<br /> 419 SetEnvIf Request_URI \.jpg image-request<br /> 420 SetEnvIf Request_URI \.png image-request<br /> 421 CustomLog logs/access_log common env=!image-request 422 </code></p></div> 423 424 425 <h3><a name="image-theft" id="image-theft">Prevent "Image Theft"</a></h3> 426 427 428 <p>This example shows how to keep people not on your server 429 from using images on your server as inline-images on their 430 pages. This is not a recommended configuration, but it can work 431 in limited circumstances. We assume that all your images are in 432 a directory called /web/images.</p> 433 434 <div class="example"><p><code> 435 SetEnvIf Referer "^http://www\.example\.com/" local_referal<br /> 436 # Allow browsers that do not send Referer info<br /> 437 SetEnvIf Referer "^$" local_referal<br /> 438 <Directory /web/images> 439 <span class="indent"> 440 Order Deny,Allow<br /> 441 Deny from all<br /> 442 Allow from env=local_referal 443 </span> 444 </Directory> 445 </code></p></div> 446 447 <p>For more information about this technique, see the 448 "<a href="http://www.serverwatch.com/tutorials/article.php/1132731">Keeping Your Images from Adorning Other Sites</a>" tutorial on 449 ServerWatch.</p> 450 451 </div></div> 452 <div class="bottomlang"> 453 <p><span>Available Languages: </span><a href="./en/env.html" title="English"> en </a> | 454 <a href="./ja/env.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | 455 <a href="./ko/env.html" hreflang="ko" rel="alternate" title="Korean"> ko </a> | 456 <a href="./tr/env.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p> 457 </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 again by our moderators if they are either implemented or considered invalid/off-topic. 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