UDP类型的 client/server 实例

基于UDP协议的网络通信主要用于消息的收发，因为它为不可靠的协议；

服务器程序：

Int main()
{
Int servfd;
Struct Sockaddr_in server_addr,client_addr;
Char buf[] = " ";
Int len = sizeof(server_addr)
Bzero(&server_addr,sizeof(server_addr));
Bzero(&client_addr, sizeof(client_addr));
Servfd = socket(AF_INET, SOCK_DGRAM, 0 );
Server_addr.sin_famliy = AF_INET;
Server_addr.sin_port = htons(2222);
Server_addr.sin_addr.s_addr = htonl(INADDR_ANY);
Blind(server_addr, (struct sockaddr *)&server_addr, len);

While(1)
{
     Recvfrom(servfd, buf, 100, 0, (struct sockaddr *)&client_addr, sizeof(client_addr));
Printf("recv %s\n",buf);
Sleep(1);
Sendto(servfd, "OK", 3, 0, (strucsockadd*)&client_addr,sizeof(client_addr));

}
Return 1;
}

客户端程序：

Int main()
{
Int clientfd;
Char buf[] = " ";
Struct sockaddr_in sockaddr;clientaddr;
Bzero(&sockaddr, sizeof(sockaddr));
Bzero(&clientaddr, sizeof(clientaddr));
Sockaddr.sin_family = AF_INET;
Sockaddr,sin_port = htons(2222);
Sockaddr.sin_addr.s_addr = inet_addr("192.168.220.155");

Clientfd = socket(AF_INET, SOCK_DGRAM, 0 );
While(1)
{
Sendto(clientfd, "hello", 6, 0, (struct sockaddr *)&clientaddr, sizeof(clientaddr));


Recvfrom(clientfd, buf, 100, 0, (struct sockaddr *)&clientaddr, sizeof(clientaddr));
Printf("recv from server is %s\n", buf);
}
Return 1;
}

运行后：实现每一秒收到来自客户端的消息：hello，而后收到服务器发来的消息：ok；