intro.pcntl.html
来自「php的帮助文档,涉及到PHP的案例和基本语法,以及实际应用内容」· HTML 代码 · 共 55 行
HTML
55 行
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html> <head> <title>Introduction</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="book.pcntl.html">PCNTL</a></div> <div class="next" style="text-align: right; float: right;"><a href="pcntl.setup.html">Installing/Configuring</a></div> <div class="up"><a href="book.pcntl.html">PCNTL</a></div> <div class="home"><a href="index.html">PHP Manual</a></div></div><hr /><div id="intro.pcntl" class="preface"> <h1 class="title">Introduction</h1> <p class="para"> Process Control support in PHP implements the Unix style of process creation, program execution, signal handling and process termination. Process Control should not be enabled within a web server environment and unexpected results may happen if any Process Control functions are used within a web server environment. </p> <p class="para"> This documentation is intended to explain the general usage of each of the Process Control functions. For detailed information about Unix process control you are encouraged to consult your systems documentation including fork(2), waitpid(2) and signal(2) or a comprehensive reference such as Advanced Programming in the UNIX Environment by W. Richard Stevens (Addison-Wesley). </p> <p class="para"> PCNTL now uses ticks as the signal handle callback mechanism, which is much faster than the previous mechanism. This change follows the same semantics as using "user ticks". You use the <b>declare()</b> statement to specify the locations in your program where callbacks are allowed to occur. This allows you to minimize the overhead of handling asynchronous events. In the past, compiling PHP with pcntl enabled would always incur this overhead, whether or not your script actually used pcntl. </p> <p class="para"> There is one adjustment that all pcntl scripts prior to PHP 4.3.0 must make for them to work which is to either to use <b>declare()</b> on a section where you wish to allow callbacks or to just enable it across the entire script using the new global syntax of <b>declare()</b>. </p> <blockquote><p><b class="note">Note</b>: <span class="simpara">This extension is notavailable on Windows platforms.</span></p></blockquote> </div><hr /><div style="text-align: center;"> <div class="prev" style="text-align: left; float: left;"><a href="book.pcntl.html">PCNTL</a></div> <div class="next" style="text-align: right; float: right;"><a href="pcntl.setup.html">Installing/Configuring</a></div> <div class="up"><a href="book.pcntl.html">PCNTL</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
增大字号Ctrl + =
减小字号Ctrl + -
显示快捷键?