libevent是一个基于事件驱动的高性能网络库。支持多种 I/O 多路复用技术， epoll、 poll、 dev/poll、 select 和 kqueue 等；支持 I/O，定时器和信号等事件；注册事件优先级。PHP libevent扩展安装：libevent扩展依赖于原始的libevent库，必须先把libevent库安装。(1)安装libevent库wget http://cloud.github.com/downloads/libevent/libevent/libevent-2.0.20-stable.tar.gz tar zxvf libevent-2.0.20-stable.tar.gz cd libevent-2.0.20-stable/ ./configure --prefix=/usr/local/libevent-2.0.20/ make make install(2)安装libevent扩展(http://pecl.php.net/package/libevent)wget http://pecl.php.net/get/libevent-0.1.0.tgz tar -zxvf libevent-0.1.0.tgz cd libevent-0.1.0 ./configure --with-php-config=/usr/local/php54/bin/php-config --with-libevent=/usr/local/libevent-2.0.20/ make && make install #php.ini添加extension=libevent.soPHP Libevent扩展介绍：(1)常量(2)函数event_base_free() 释放资源，这不能销毁绑定事件event_base_loop() 处理事件，根据指定的base来处理事件循环event_base_loopbreak() 立即取消事件循环，行为各break语句相同event_base_loopexit() 在指定的时间后退出循环event_base_new() 创建并且初始事件event_base_priority_init() 设定事件的优先级event_base_set() 关联事件到事件baseevent_buffer_base_set() 关联缓存的事件到event_baseevent_buffer_disable() 禁用一个缓存的事件event_buffer_enable() 启用一个指定的缓存的事件event_buffer_fd_set() 改变一个缓存的文件系统描述event_buffer_free() 释放缓存事件event_buffer_new() 建立一个新的缓存事件event_buffer_priority_set() 缓存事件的优先级设定event_buffer_read() 读取缓存事件中的数据event_buffer_set_callback() 给缓存的事件设置或重置回调hansh函数event_buffer_timeout_set() 给一个缓存的事件设定超时的读写时间event_buffer_watermark_set 设置读写事件的水印标记event_buffer_write() 向缓存事件中写入数据event_add() 向指定的设置中添加一个执行事件event_del() 从设置的事件中移除事件event_free() 清空事件句柄event_new() 创建一个新的事件event_set() 准备想要在event_add中添加事件PHP Libevent扩展使用：例1:5s后触发callback$base = event_base_new(); $event = event_new(); event_set($event, 0, EV_TIMEOUT, function() { echo "function called"; }); event_base_set($event, $base); event_add($event, 5000000); event_base_loop($base);例2：打印输入流function print_line($fd, $events, $arg) { static $max_requests = 0; $max_requests++; if ($max_requests == 10) { // exit loop after 10 writes event_base_loopexit($arg[1]); } echo fgets($fd); } // create base and event $base = event_base_new(); $event = event_new(); $fd = STDIN; // set event flags event_set($event, $fd, EV_READ | EV_PERSIST, 'print_line', array($event, $base)); // set event base event_base_set($event, $base); // enable event event_add($event); // start event loop event_base_loop($base);例3：实现简单web server在cli执行后，打开浏览器2000端口试试看。$socket = stream_socket_server ('tcp://0.0.0.0:2000', $errno, $errstr); stream_set_blocking($socket, 0); $base = event_base_new(); $event = event_new(); event_set($event, $socket, EV_READ | EV_PERSIST, 'ev_accept', $base); event_base_set($event, $base); event_add($event); event_base_loop($base); function ev_accept($socket, $flag, $base) { $connection = stream_socket_accept($socket); stream_set_blocking($connection, 0); $buffer = event_buffer_new($connection, 'ev_read', NULL, 'ev_error', $connection); event_buffer_base_set($buffer, $base); event_buffer_timeout_set($buffer, 30, 30); event_buffer_watermark_set($buffer, EV_READ, 0, 0xffffff); event_buffer_priority_set($buffer, 10); event_buffer_enable($buffer, EV_READ | EV_PERSIST); $GLOBALS['_'] = $buffer; //这个buffer一定要赋给个全局的变量 貌似是传值过程中的bug 或者5.3.8的闭包还是有问题？ } function ev_error($buffer, $error, $connection) { event_buffer_disable($buffer, EV_READ | EV_WRITE); event_buffer_free($buffer); fclose($connection); } function ev_read($buffer, $connection) { while ($read = event_buffer_read($buffer, 256)) { } fwrite($connection , date('Y-m-d H:i:s')); ev_error($buffer , '' , $connection); }参考资料：http://blog.csdn.net/laoyi_grace/article/details/6539244http://www.ibm.com/developerworks/cn/aix/library/au-libev/index.htmlhttp://blog.csdn.net/shagoo/article/details/6396089