[国嵌攻略][092][UDP网络程序设计]

#include <sys/socket.h>
#include <netinet/in.h>
#include <strings.h>
#include <stdio.h>

#define SERVER_PORT 3333

void main(){
//创建标识
int serverfd;

serverfd = socket(AF_INET, SOCK_DGRAM, 0);   //建立UDP连接

//绑定地址
struct sockaddr_in serverAddr;

serverAddr.sin_family = AF_INET;                   //设置协议
serverAddr.sin_port = htons(SERVER_PORT);          //设置端口
serverAddr.sin_addr.s_addr = htonl(INADDR_ANY);    //设置地址
bzero(serverAddr.sin_zero, 8);                     //设置为零

bind(serverfd, (struct sockaddr *)&serverAddr, sizeof(struct sockaddr));

//接收数据
char buffer[2048];
struct sockaddr_in clientAddr;
socklen_t clientAddrLen;

clientAddrLen = sizeof(struct sockaddr);
recvfrom(serverfd, buffer, sizeof(buffer), 0, (struct sockaddr *)&clientAddr, &clientAddrLen);

//显示数据
char *clientIPAddr;

clientIPAddr = (char *)inet_ntoa(clientAddr.sin_addr.s_addr);
printf("server recvice from %s:\n%s", clientIPAddr, buffer);

//关闭连接
close(serverfd);
}

#include <sys/socket.h>
#include <netinet/in.h>
#include <strings.h>
#include <stdio.h>

#define SERVER_PORT 3333

int main(int argc, char **argv){
//参数检查
if(argc != 2){
printf("Usage:\n\t%s <ip address>\n", argv[0]);
return -1;
}

//创建标识
int clientfd;

clientfd = socket(AF_INET, SOCK_DGRAM, 0);   //建立UDP连接

//输入数据
char buffer[2048];

printf("client send to %s:\n", argv[1]);
fgets(buffer, sizeof(buffer), stdin);

//发送数据
struct sockaddr_in serverAddr;

serverAddr.sin_family = AF_INET;                   //设置协议
serverAddr.sin_port = htons(SERVER_PORT);          //设置端口
serverAddr.sin_addr.s_addr = inet_addr(argv[1]);   //设置地址
bzero(serverAddr.sin_zero, 8);                     //设置为零

sendto(clientfd, buffer, sizeof(buffer), 0, (struct sockaddr *)&serverAddr, sizeof(struct sockaddr));

//关闭连接
close(clientfd);

return 0;
}