本文共 5348 字，大约阅读时间需要 17 分钟。
http://blog.csdn.net/libinbin_1014/article/details/50096187
/*gcc -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -I${ORACLE_HOME}/rdbms/public -I${ORACLE_HOME}/rdbms/demo -L${ORACLE_HOME}/lib -lclntsh -pthread -o epoll_server epoll_server.c*/#include #include #include #include #include #include #include #include #include #include #include #include #include #include #define MAXBUF 1024#define MAXEPOLLSIZE 10000/*setnonblocking - 设置句柄为非阻塞方式*/int setnonblocking(int sockfd){ if (fcntl(sockfd, F_SETFL, fcntl(sockfd, F_GETFD, 0)|O_NONBLOCK) == -1) { return -1; } return 0;}/*handle_message - 处理每个 socket 上的消息收发*/int handle_message(int new_fd){ char buf[MAXBUF + 1]; char sendbuf[MAXBUF+1]; int len; /* 开始处理每个新连接上的数据收发 */ bzero(buf, MAXBUF + 1); /* 接收客户端的消息 */ len = recv(new_fd, buf, MAXBUF, 0); if (len > 0){ printf("%d接收消息成功:'%s'，共%d个字节的数据/n",new_fd, buf, len); } else { if (len < 0) printf("消息接收失败！错误代码是%d，错误信息是'%s'/n",errno, strerror(errno)); else printf("客户端%d退出!/n",new_fd); return -1; } /* 处理每个新连接上的数据收发结束 */ return len;}int main(int argc, char **argv){ int listener, new_fd, nfds, n, ret; struct epoll_event ev; int kdpfd, curfds; socklen_t len; struct sockaddr_in my_addr, their_addr; unsigned int myport, lisnum; struct epoll_event events[MAXEPOLLSIZE]; struct rlimit rt; if (argc>1) myport = atoi(argv[1]); else myport = 1234; if (argc>2) lisnum = atoi(argv[2]); else lisnum = 10; /* 设置每个进程允许打开的最大文件数 */ rt.rlim_max = rt.rlim_cur = MAXEPOLLSIZE; if (setrlimit(RLIMIT_NOFILE, &rt) == -1) { perror("setrlimit"); exit(1); } else printf("设置系统资源参数成功！/n"); /* 开启 socket 监听 */ if ((listener = socket(PF_INET, SOCK_STREAM, 0)) == -1) { perror("socket"); exit(1); } else printf("socket 创建成功！/n"); /*设置socket属性，端口可以重用*/ int opt=SO_REUSEADDR; setsockopt(listener,SOL_SOCKET,SO_REUSEADDR,&opt,sizeof(opt)); /*设置socket为非阻塞模式*/ setnonblocking(listener); bzero(&my_addr, sizeof(my_addr)); my_addr.sin_family = PF_INET; my_addr.sin_port = htons(myport); if (argc>3) my_addr.sin_addr.s_addr = inet_addr(argv[3]); else my_addr.sin_addr.s_addr = INADDR_ANY; if (bind(listener, (struct sockaddr *) &my_addr, sizeof(struct sockaddr))== -1) { perror("bind"); exit(1); } else printf("IP 地址和端口绑定成功/n"); if (listen(listener, lisnum) == -1) { perror("listen"); exit(1); } else printf("开启服务成功！/n"); /* 创建 epoll 句柄，把监听 socket 加入到 epoll 集合里 */ kdpfd = epoll_create(MAXEPOLLSIZE); len = sizeof(struct sockaddr_in); ev.events = EPOLLIN | EPOLLET; ev.data.fd = listener; if (epoll_ctl(kdpfd, EPOLL_CTL_ADD, listener, &ev) < 0) { fprintf(stderr, "epoll set insertion error: fd=%d/n", listener); return -1; } else printf("监听 socket 加入 epoll 成功！/n"); curfds = 1; while (1) { /* 等待有事件发生 */ nfds = epoll_wait(kdpfd, events, curfds, -1); if (nfds == -1) { perror("epoll_wait"); break; } /* 处理所有事件 */ for (n = 0; n < nfds; ++n) { if (events[n].data.fd == listener) { new_fd = accept(listener, (struct sockaddr *) &their_addr, &len); if (new_fd < 0) { perror("accept"); continue; else printf("有连接来自于：%s:%d，分配的 socke为:%d/n",inet_ntoa(their_addr.sin_addr), ntohs(their_addr.sin_port), new_fd); setnonblocking(new_fd); ev.events = EPOLLIN | EPOLLET; ev.data.fd = new_fd; if (epoll_ctl(kdpfd, EPOLL_CTL_ADD, new_fd, &ev) < 0) { fprintf(stderr, "把 socket '%d' 加入 epoll 失败！%s/n", new_fd, strerror(errno)); return -1; } curfds++; } else { ret = handle_message(events[n].data.fd); if (ret < 1 && errno != 11) { if(epoll_ctl(kdpfd, EPOLL_CTL_DEL, events[n].data.fd, &ev) < 0) { fprintf(stderr, "把 socket '%d' 从 epoll 删除失败！%s/n", events[n].data.fd, strerror(errno)); } curfds--; close(events[n].data.fd); } } } } close(listener); return 0;} tcp客户端client.c:#include#include #include #include #include #include #include #include #include #include #include #define MAXLINE 1024char sendhead[MAXLINE];int main(int argc , char* argv[]){ int sockfd; struct sockaddr_in servaddr; char *info="cxt"; int maxfdp1, stdineof; fd_set rset; char recvbuf[MAXLINE],tmp[128],sendbuf[MAXLINE]; int n,len,fd; if(argc!=3){ printf("useage:client address port "); exit(0); } if((sockfd=socket(AF_INET,SOCK_STREAM,0))==-1 ) { perror("socket"); exit(1); } printf("%s connect server/n",info); bzero(&servaddr,sizeof(servaddr)); servaddr.sin_family=AF_INET; servaddr.sin_port=htons(atoi(argv[2])); inet_pton(AF_INET,argv[1],&servaddr.sin_addr); if( ( connect(sockfd,(struct sockaddr*)&servaddr,sizeof(servaddr)) )<0) { perror("connect"); exit(1); } send(sockfd,info,strlen(info),0); for ( ; ; ) { FD_ZERO(&rset); FD_SET(sockfd, &rset); FD_SET(0, &rset); maxfdp1=sockfd+1; if((select(maxfdp1, &rset, NULL, NULL, NULL) )<=0){ perror("select"); }else{ if (FD_ISSET(0,&rset)){ fgets(sendbuf, MAXLINE, stdin); n=send(sockfd,sendbuf,strlen(sendbuf)-1,0); if(n>0) printf("send: %s",sendbuf); else printf("send: %s error,the erro cause is %s:%s/n",sendbuf,errno,strerror(errno)); bzero(sendbuf,strlen(sendbuf)); } if (FD_ISSET(sockfd, &rset)) { /* socket is readable */ n=recv(sockfd, recvbuf, MAXLINE,0) ; if(n<0) { perror("str_cli: server terminated prematurely"); }else if(n==0) { printf("sever shutdown!"); exit(-1); } //recvbuf recvbuf[n]='/0'; printf("receive :%s/n",recvbuf); fflush(stdout); bzero(recvbuf,strlen(recvbuf)); } } } exit(0);}