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/*- * Copyright (c) 1999 Lu Jiandong lujiandong1001@yahoo.com.cn * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. *//* * kqueue 实现的定时器 * kqueue 是FreeBSD操作系统提供的一套高性能，通用的“事件”通知机制。它的最常见应用是网络编程中获取可以读写的socket。 * 它还可以提供定时器，文件操作等通知功能。 */#include#include #include #include #include #include #include
struct kevent { uintptr_t ident; /* 事件 ID */ short filter; /* 事件过滤器 */ u_short flags; /* 行为标识 */ u_int fflags; /* 过滤器标识值 */ intptr_t data; /* 过滤器数据 */ void *udata; /* 应用透传数据 */ }; 在一个 kqueue 中，{ident, filter} 确定一个唯一的事件。 void test(){int kqueuefd = kqueue();struct kevent ev; //在给定的描述符上由内核来对这个过滤器进行监控(有好多不同的过滤器) EV_SET(&ev, -1, EVFILT_TIMER, EV_ADD | EV_ENABLE, 0, 40, NULL); //40 milliseconds kevent(kqueuefd, &ev, 1, NULL, 0, NULL); struct kevent newev; int count = -1; while(1) { count = kevent(kqueuefd, NULL, 0, &newev, 1, NULL); if (!count){ printf("no event\n"); continue; } struct timeval tv; gettimeofday(&tv, NULL); printf("time :sec = %u usec = %u\n", tv.tv_sec, tv.tv_usec); usleep(30); } }int main(int argc, char *argv[]){ test(); return 0; 转载地址：http://klgyi.baihongyu.com/