udpserver.c

linux下的udp socket通信

#include <sys/types.h>
#include <sys/socket.h>
#include <string.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>


#define MAXSIZE 80
#define SERV_PORT 8888


void do_echo(int sockfd, struct sockaddr *pcliaddr, socklen_t clilen)
{
	int n;
	socklen_t len;
	char mesg[MAXSIZE];

	for(;;)
	{

		len = clilen;

		n = recvfrom(sockfd, mesg, MAXSIZE, 0, pcliaddr, &len);
		/*if (n > 0)
		{
			printf("receive it\n");
			mesg[n] = '\0';
			fputs(recvline, stdout);

		}*/

		sendto(sockfd, mesg, n, 0, pcliaddr, len);

		usleep(1);

	}

}


int main(void)
{
	int sockfd;
	struct sockaddr_in seraddr,cliaddr;

	sockfd = socket(PF_INET, SOCK_DGRAM, 0);

	memset(&seraddr, 0, sizeof(seraddr));
	seraddr.sin_family = AF_INET;
	seraddr.sin_addr.s_addr = inet_addr("192.168.98.127");
	seraddr.sin_port = htons(SERV_PORT);
	bzero(&(seraddr.sin_zero), 8);

	if(bind(sockfd, (struct sockaddr *)&seraddr, sizeof(seraddr))==-1)
	{

		perror("bind error!/n");
		exit(1);

	}

	do_echo(sockfd, (struct sockaddr *)&cliaddr,sizeof(cliaddr));

	close(sockfd);

	return 0;



}