u_server.c

在vc++6.0环境下实现的u_server(服务器端)

// U_server.cpp : 定义控制台应用程序的入口点。
//


// Server.cpp : Defines the entry point for the console application.
//

/*
#include "stdafx.h"

int main(int argc, char* argv[])
{
	printf("Hello World!\n");
	return 0;
}
*/
#include "stdafx.h"
#include <Winsock2.h>
#include <stdio.h>
#include <stdlib.h>
#define DEFAULT_PORT 5050 //服务端默认端口

int main(int argc, char* argv[])
{
	int		iPort = DEFAULT_PORT;
	WSADATA	wsaData;
	SOCKET	sServer;
	int		iLen; //客户地址长度
	int     iRecv;
	int		iSend;//发送数据长度
	char        buf[100];
	char		msg[] = "Hello，my name is Jerry.";//要发送给客户的信息
	struct sockaddr_in ser,cli;//服务器和客户的地址
	memset(buf,0,sizeof(buf));//接收缓冲区初始化
	if(WSAStartup(MAKEWORD(2,2),&wsaData)!=0)
	{
		printf("Failed to load Winsock.\n");
		return -1;
	}
	
	sServer = socket(AF_INET,SOCK_DGRAM,0);//创建服务器端套接口
	if(sServer == INVALID_SOCKET)
	{
		printf("socket() Failed: %d\n",WSAGetLastError());
		return -1;
	}
	//以下建立服务器端地址
	//使用IP地址族
	ser.sin_family = AF_INET;
	//使用htons()把双字节主机序端口号转换为网络字节序端口号
	ser.sin_port = htons(iPort);
	//htonl()把一个四字节主机序IP地址转换为网络字节序主机地址
	//使用系统指定的IP地址INADDR_ANY
	ser.sin_addr.s_addr = htonl(INADDR_ANY); 
	//bind()函数进行套接字与地址的绑定

	if(bind(sServer,(LPSOCKADDR)&ser,sizeof(ser)) == SOCKET_ERROR)
	{
		printf("bind() Failed: %d\n",WSAGetLastError());
		return -1;
	}
	iLen=sizeof(cli);
	iRecv =recvfrom(sServer,buf,sizeof(buf),0,(LPSOCKADDR)&cli,&iLen);
	if(iRecv == 0) 
		return -1;
	else if(iRecv == SOCKET_ERROR)
	{
		printf("recvfrom() Failed: %d\n",WSAGetLastError());
		return -1;
	}
	else
		printf("recvfrom() data from client: %s\n",buf);

	iSend = sendto(sServer,msg,sizeof(msg),0,(LPSOCKADDR)&cli,sizeof(cli));
	if(iSend == SOCKET_ERROR)
	{
		printf("sendto() Failed: %d\n",WSAGetLastError());
	}
	else
	{
		printf("sendto() byte: %d\n",iSend);
	}
	shutdown(sServer,SD_BOTH);
	closesocket(sServer);
	WSACleanup();
	return 0;
}