UDP通信程序（服務器）

/*===========================================================================
 Name        : Server.c
 Author      : Haier
 Version     : 1.0
 Copyright   : Your copyright notice
 Description : Server in C, Ansi-style,Compile by Gcc
 ============================================================================*/

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

#define LISTENPORT (6000)
#define BUFSIZE	   (1024)

int main(int argc,char *argv[])
{
	int ServerSocket;
	struct sockaddr_in ServerAddr;
	fd_set Readfds;
	int SelectSocket;
	struct timeval TimeOut={0,0};
	int AddrLen;
	int MessageLen;
	struct sockaddr_in ClientAddr;
	char Buf[BUFSIZE];

	ServerSocket=socket(PF_INET,SOCK_DGRAM,IPPROTO_UDP);
	if(ServerSocket<0)
	{
		printf("Socket Failed !\n");
		exit(0);
	}

	memset(&ServerAddr,0,sizeof(ServerAddr));
	ServerAddr.sin_family=AF_INET;
	ServerAddr.sin_addr.s_addr=htonl(INADDR_ANY);
	ServerAddr.sin_port=htons((unsigned short)LISTENPORT);

	if(bind(ServerSocket,(struct sockaddr *)&ServerAddr,sizeof(ServerAddr))<0)
	{
		printf("Bind Failed !\n");
		exit(0);
	}

	while(1)
	{
		do
		{
			FD_ZERO(&Readfds);
			FD_SET(ServerSocket,&Readfds);
			SelectSocket=select(ServerSocket+1,&Readfds,NULL,NULL,&TimeOut);

			if(SelectSocket>0)
			{
				AddrLen=sizeof(ClientAddr);
				MessageLen=recvfrom(ServerSocket,Buf,BUFSIZE,0,(struct sockaddr*)&ClientAddr,&AddrLen);

				if(MessageLen>0)
				{
					Buf[MessageLen]='\0';
					printf("Recvice form %s : %s\n",inet_ntoa(ClientAddr.sin_addr),Buf);
				}
			}
		}while(SelectSocket>0);

		if(strcmp(Buf,"shutdown")==0)
		{
			break;
		}
	}

	close(ServerSocket);
	return 0;
}