📄 function.putenv.html
字号:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html> <head> <title>Sets the value of an environment variable</title> <meta http-equiv="content-type" content="text/html; charset=UTF-8"> </head> <body><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.phpversion.html">phpversion</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.restore-include-path.html">restore_include_path</a></div> <div class="up"><a href="ref.info.html">PHP Options/Info Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="function.putenv" class="refentry"> <div class="refnamediv"> <h1 class="refname">putenv</h1> <p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">putenv</span> — <span class="dc-title">Sets the value of an environment variable</span></p> </div> <div class="refsect1 description"> <h3 class="title">Description</h3> <div class="methodsynopsis dc-description"> <span class="type">bool</span> <span class="methodname"><b><b>putenv</b></b></span> ( <span class="methodparam"><span class="type">string</span> <tt class="parameter">$setting</tt></span> )</div> <p class="para rdfs-comment"> Adds <i><tt class="parameter">setting</tt></i> to the server environment. The environment variable will only exist for the duration of the current request. At the end of the request the environment is restored to its original state. </p> <p class="para"> Setting certain environment variables may be a potential security breach. The <i>safe_mode_allowed_env_vars</i> directive contains a comma-delimited list of prefixes. In Safe Mode, the user may only alter environment variables whose names begin with the prefixes supplied by this directive. By default, users will only be able to set environment variables that begin with <i>PHP_</i> (e.g. <i>PHP_FOO=BAR</i>). Note: if this directive is empty, PHP will let the user modify ANY environment variable! </p> <p class="para"> The <i>safe_mode_protected_env_vars</i> directive contains a comma-delimited list of environment variables, that the end user won't be able to change using <b>putenv()</b>. These variables will be protected even if <i>safe_mode_allowed_env_vars</i> is set to allow to change them. </p> </div> <div class="refsect1 parameters"> <h3 class="title">Parameters</h3> <p class="para"> <dl> <dt> <span class="term"><i><tt class="parameter">setting</tt></i></span> <dd> <p class="para"> The setting, like <i>"FOO=BAR"</i> </p> </dd> </dt> </dl> </p> </div> <div class="refsect1 returnvalues"> <h3 class="title">Return Values</h3> <p class="para"> Returns <b><tt>TRUE</tt></b> on success or <b><tt>FALSE</tt></b> on failure. </p> </div> <div class="refsect1 examples"> <h3 class="title">Examples</h3> <p class="para"> <div class="example"> <p><b>Example #1 Setting an environment variable</b></p> <div class="example-contents"><div class="phpcode"><code><span style="color: #000000"><span style="color: #0000BB"><?php<br />putenv</span><span style="color: #007700">(</span><span style="color: #DD0000">"UNIQID=$uniqid"</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span></span></code></div> </div> </div> </p> </div> <div class="refsect1 notes"> <h3 class="title">Notes</h3> <div class="warning"><b class="warning">Warning</b> <p class="para"> These directives have only effect when <a href="features.safe-mode.html" class="link">safe-mode</a> itself is enabled! </p> </div> </div> <div class="refsect1 seealso"> <h3 class="title">See Also</h3> <p class="para"> <ul class="simplelist"> <li class="member"><a href="function.getenv.html" class="function" rel="rdfs-seeAlso">getenv()</a></li> </ul> </p> </div></div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="function.phpversion.html">phpversion</a></div> <div class="next" style="text-align: right; float: right;"><a href="function.restore-include-path.html">restore_include_path</a></div> <div class="up"><a href="ref.info.html">PHP Options/Info Functions</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div></body></html>⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -