Windows下C语言的Socket编程例子（TCP和UDP）

刚刚学windows编程，所以想写学习笔记，这是一个简单的Socket程序例子，开发环境是vc6：

首先是TCP

server端：

#include "stdafx.h"
#include <stdio.h>
#include <winsock2.h>

#pragma comment(lib,"ws2_32.lib")

int main(int argc, char* argv[])
{
	//初始化WSA
	WORD sockVersion = MAKEWORD(2,2);
	WSADATA wsaData;
	if(WSAStartup(sockVersion, &wsaData)!=0)
	{
		return 0;
	}

	//创建套接字
	SOCKET slisten = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
	if(slisten == INVALID_SOCKET)
	{
		printf("socket error !");
		return 0;
	}

	//绑定IP和端口
	sockaddr_in sin;
	sin.sin_family = AF_INET;
	sin.sin_port = htons(8888);
	sin.sin_addr.S_un.S_addr = INADDR_ANY; 
	if(bind(slisten, (LPSOCKADDR)&sin, sizeof(sin)) == SOCKET_ERROR)
	{
		printf("bind error !");
	}

	//开始监听
	if(listen(slisten, 5) == SOCKET_ERROR)
	{
		printf("listen error !");
		return 0;
	}

	//循环接收数据
	SOCKET sClient;
	sockaddr_in remoteAddr;
	int nAddrlen = sizeof(remoteAddr);
	char revData[255]; 
	while (true)
	{
		printf("等待连接...\n");
		sClient = accept(slisten, (SOCKADDR *)&remoteAddr, &nAddrlen);
		if(sClient == INVALID_SOCKET)
		{
			printf("accept error !");
			continue;
		}
		printf("接受到一个连接：%s \r\n", inet_ntoa(remoteAddr.sin_addr));
		
		//接收数据
		int ret = recv(sClient, revData, 255, 0);		
		if(ret > 0)
		{
			revData[ret] = 0x00;
			printf(revData);
		}

		//发送数据
		char * sendData = "你好，TCP客户端！\n";
		send(sClient, sendData, strlen(sendData), 0);
		closesocket(sClient);
	}
	
	closesocket(slisten);
	WSACleanup();
	return 0;
}

client端：

#include "stdafx.h"
#include <WINSOCK2.H>
#include <STDIO.H>

#pragma  comment(lib,"ws2_32.lib")


int main(int argc, char* argv[])
{
	WORD sockVersion = MAKEWORD(2,2);
	WSADATA data; 
	if(WSAStartup(sockVersion, &data) != 0)
	{
		return 0;
	}

	SOCKET sclient = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
	if(sclient == INVALID_SOCKET)
	{
		printf("invalid socket !");
		return 0;
	}

	sockaddr_in serAddr;
	serAddr.sin_family = AF_INET;
	serAddr.sin_port = htons(8888);
	serAddr.sin_addr.S_un.S_addr = inet_addr("127.0.0.1"); 
	if (connect(sclient, (sockaddr *)&serAddr, sizeof(serAddr)) == SOCKET_ERROR)
	{
		printf("connect error !");
		closesocket(sclient);
		return 0;
	}
	char * sendData = "你好，TCP服务端，我是客户端!\n";
	send(sclient, sendData, strlen(sendData), 0);

	char recData[255];
	int ret = recv(sclient, recData, 255, 0);
	if(ret > 0)
	{
		recData[ret] = 0x00;
		printf(recData);
	}
	closesocket(sclient);
	WSACleanup();
	return 0;
}

然后是UDP

server端：

#include "stdafx.h"
#include <stdio.h>
#include <winsock2.h>

#pragma comment(lib, "ws2_32.lib") 

int main(int argc, char* argv[])
{
	WSADATA wsaData;
	WORD sockVersion = MAKEWORD(2,2);
	if(WSAStartup(sockVersion, &wsaData) != 0)
	{
		return 0;
	}

	SOCKET serSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); 
	if(serSocket == INVALID_SOCKET)
	{
		printf("socket error !");
		return 0;
	}

	sockaddr_in serAddr;
	serAddr.sin_family = AF_INET;
	serAddr.sin_port = htons(8888);
	serAddr.sin_addr.S_un.S_addr = INADDR_ANY;
	if(bind(serSocket, (sockaddr *)&serAddr, sizeof(serAddr)) == SOCKET_ERROR)
	{
		printf("bind error !");
		closesocket(serSocket);
		return 0;
	}
	
	sockaddr_in remoteAddr;
	int nAddrLen = sizeof(remoteAddr); 
	while (true)
	{
		char recvData[255];  
		int ret = recvfrom(serSocket, recvData, 255, 0, (sockaddr *)&remoteAddr, &nAddrLen);
		if (ret > 0)
		{
			recvData[ret] = 0x00;
			printf("接受到一个连接：%s \r\n", inet_ntoa(remoteAddr.sin_addr));
			printf(recvData);			
		}

		char * sendData = "一个来自服务端的UDP数据包\n";
		sendto(serSocket, sendData, strlen(sendData), 0, (sockaddr *)&remoteAddr, nAddrLen);	

	}
	closesocket(serSocket); 
	WSACleanup();
	return 0;
}

client端：

#include "stdafx.h"
#include <stdio.h>
#include <winsock2.h>

#pragma comment(lib, "ws2_32.lib") 

int main(int argc, char* argv[])
{
	WORD socketVersion = MAKEWORD(2,2);
	WSADATA wsaData; 
	if(WSAStartup(socketVersion, &wsaData) != 0)
	{
		return 0;
	}
	SOCKET sclient = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
	
	sockaddr_in sin;
	sin.sin_family = AF_INET;
	sin.sin_port = htons(8888);
	sin.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");
	int len = sizeof(sin);
	
	char * sendData = "来自客户端的数据包.\n";
	sendto(sclient, sendData, strlen(sendData), 0, (sockaddr *)&sin, len);

	char recvData[255]; 	
	int ret = recvfrom(sclient, recvData, 255, 0, (sockaddr *)&sin, &len);
	if(ret > 0)
	{
		recvData[ret] = 0x00;
		printf(recvData);
	}

	closesocket(sclient);
	WSACleanup();
	return 0;
}

测试是可以通过的，就是不知道有那些地方可以改进，那些地方是可以删除的，如果有人知道可以给我留言。