应用AF_INET实现UDP点对点通信示例
使用AF_INET实现UDP点对点通信示例
此示例程序实现AF_INET实现UDP点对点通信示例,即采用AF_INET协议,数据传送方式为UDP数据报方式,主要功能是发送方向接收方发送一条简单的消息“hello world!”.
服务器端要先运行,然后运行客户端程序
客户端程序代码:
#include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <errno.h> #include <arpa/inet.h> int main(int argc,char *argv[]) { struct sockaddr_in s_addr; int sock; int addr_len; int len; char buff[128]; if((sock=socket(AF_INET,SOCK_DGRAM,0))==-1) { perror("socket"); exit(1); } else printf("sock init done\n"); s_addr.sin_family = AF_INET; s_addr.sin_port = htons(7838); if(argv[1]) s_addr.sin_addr.s_addr = inet_addr(argv[1]); else { printf("input server ip\n"); exit(0); } addr_len = sizeof(s_addr); strcpy(buff,"hello,world"); len=sendto(sock,buff,strlen(buff),0,(struct sockaddr *)&s_addr,addr_len); if(len<0) { perror("sendto"); exit(1); } printf("send sucess"); return 0; }
服务器端程序代码:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <errno.h>
#include <arpa/inet.h>
int main()
{
struct sockaddr_in s_addr;
struct sockaddr_in c_addr;
int sock;
socklen_t addr_len;
int len;
char buff[128];
if((sock=socket(AF_INET,SOCK_DGRAM,0))==-1)
{
perror("socket");
exit(1);
}
else
printf("create socket\n");
memset(&s_addr,0,sizeof(s_addr));
s_addr.sin_family = AF_INET;
s_addr.sin_port = htons(7838);
s_addr.sin_addr.s_addr=INADDR_ANY;
if(bind(sock,(struct sockaddr *)&s_addr,sizeof(s_addr))==-1)
{
perror("bind");
exit(1);
}
else
printf("bind address to sock.\n\r");
addr_len=sizeof(c_addr);
while(1)
{
len = recvfrom(sock,buff,sizeof(buff)-1,0,(struct sockaddr *)&c_addr,&addr_len);
if(len<0)
{
perror("recvfrom");
exit(1);
}
buff[len]='\0';
printf("receive come from %s:%d message:%s\n\r",
inet_ntoa(c_addr.sin_addr),ntohs(c_addr.sin_port),buff);
}
return 0;
}