中南大学实验:SOCKET通信TCP协议-发送数字1到数字100

#include<stdio.h> #include<string.h> #include<stdlib.h> #include<unistd.h> #include<sys/types.h> #include<sys/socket.h> #include<netinet/in.h> #include<arpa/inet.h> #define PORT 1234 // 端口号 #define BACKLOG 1 // 允许连接的数量 int main() { int listenfd, connectfd; /*定义服务器和客户端的IPv4套接字地址*/ struct sockaddr_in server; struct sockaddr_in client; int sin_size; if ((listenfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) { perror("Creating socket failed!"); exit(1); } int opt = SO_REUSEADDR; /* 设置允许重用本地地址*/ setsockopt(listenfd, SOL_SOCKET, SO_REUSEADDR, &opt, sizeof(opt)); bzero(&server, sizeof(server)); server.sin_family = AF_INET; /*htons是将无符号短整型（16位）的变量从主机字节顺序转变成网络字节顺序*/ server.sin_port = htons(PORT); /*htonl将一个32位数从主机字节顺序转换成 无符号长整型的网络字节顺序*/ /*INADDR_ANY就是指定地址为0.0.0.0的地址*/ /*给32位的IPv4地址赋值*/ server.sin_addr.s_addr = htonl(INADDR_ANY); /*bind把本地协议地址赋予一个套接字*/ /*协议地址：32位IPv4地址或128位的IPv6地址 与 16位的TCP/UDP端口的组合*/ if(bind(listenfd, (struct sockaddr *)&server, sizeof(struct sockaddr)) == -1) { perror("Bind error!"); exit(1); } printf("bind successfully!"); if(listen(listenfd, BACKLOG) == -1) { perror("listen error!"); exit(1); } printf("listening!"); sin_size = sizeof(struct sockaddr_in); if ((connectfd = accept(listenfd, (struct sockaddr *)&client, &sin_size)) == -1) { perror("accept error!"); exit(1); } printf("You get a connetion from %s\n", inet_ntoa(client.sin_addr)); for(int i = 1; i <= 100; i++) { char a[10]; sprintf(a,"数字%d", i); //send(connectfd, a, 10, 0); write(connectfd, a, 10); sleep(1); } close(connectfd); close(listenfd); }