Linux 网络编程(多路复用)
- 服务器端代码
#include<stdio.h> #include<stdlib.h> #include<string.h> #include<sys/socket.h> #include<sys/types.h> #include<unistd.h> #include<netinet/in.h> #include <errno.h> #include <sys/fcntl.h> typedef struct _CLIENT{ int fd; struct sockaddr_in addr; char recvbuf[1024]; }CLIENT_S; int main(int argc, char** argv){ int socketfd,new_fd; CLIENT_S sock_list[10]; struct sockaddr_in server_addr; struct sockaddr_in client_addr; struct timeval tv; char recvbuf[1024]; int res; int max; int len,nbytes; int port = 8001; int i; for(i = 0; i < 10; i ++){ sock_list[i].fd = -1; } if((socketfd = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) == 0){ fprintf(stderr, "socket Error:%s\n\a", strerror(errno)); exit(1); } //设置为非阻塞 if (fcntl(socketfd, F_SETFL, O_NONBLOCK) == -1) { fprintf(stderr, "fcntl Error:%s\n\a", strerror(errno)); exit(1); } bzero(&server_addr, sizeof(struct sockaddr_in)); server_addr.sin_family = AF_INET; server_addr.sin_port = htons(port); server_addr.sin_addr.s_addr = htonl(INADDR_ANY); if((bind(socketfd, &server_addr, sizeof(server_addr))) == -1){ fprintf(stderr, "bind Error:%s\n\a", strerror(errno)); exit(1); } if(listen(socketfd, 10) == -1){ fprintf(stderr, "listen Error:%s\n\a", strerror(errno)); exit(1); } sock_list[0].fd = socketfd; max = socketfd; fd_set watchset;//select所需要的文件描述符 FD_ZERO(&watchset); //将监听socket放入扫描集合 FD_SET(socketfd, &watchset); while(1){ FD_ZERO(&watchset); FD_SET(socketfd, &watchset); for(i = 0; i < 10; i ++){ if (sock_list[i].fd != -1) { FD_SET(sock_list[i].fd, &watchset); } } res = select(max + 1, &watchset, NULL, NULL, NULL); if(-1 == res){ fprintf(stderr, "select Error:%s\n\a", strerror(errno)); exit(1); }else if(0 == res){ printf("Select() break and the return num is"); continue; }else{ if(FD_ISSET(socketfd, &watchset)){ len = sizeof(struct sockaddr_in); if ((new_fd = accept(socketfd, (struct sockaddr *)&client_addr, &len)) == -1) { fprintf(stderr, "Accept error:%s\n\a", strerror(errno)); exit(1); } for(i = 1; i < 10; i ++){ if (sock_list[i].fd == -1) { sock_list[i].fd = new_fd; sock_list[i].addr = client_addr; break; } } fprintf(stderr, "new connect: %d\n", sock_list[i].fd); //将其放入socket的监听集合 FD_SET(new_fd, &watchset); if (max < new_fd) { max = new_fd; } continue; }else{ for (i = 1; i < 10; i++) { //data if (sock_list[i].fd == -1) continue; if (!FD_ISSET(sock_list[i].fd, &watchset)) { continue; } nbytes = recv(sock_list[i].fd, sock_list[i].recvbuf, sizeof(sock_list[i].recvbuf), 0); recvbuf[nbytes] = '\0'; printf("recv data is:%s\n",sock_list[i].recvbuf); break; } } } }//while(1) exit(0); }