主要理解select函数,涉及到一些 宏和 数组定义

分为两端

Server端:

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

//



#include "stdafx.h"

#include <string.h>

#include <stdlib.h>



#include <Winsock2.h>

#pragma comment(lib,"Ws2_32.lib")





SOCKET gClientSockAddr[FD_SETSIZE]={0};

DWORD gClientSockNum = 0;

HANDLE ghMutex = NULL;

DWORD WINAPI RecvSendThead(LPVOID lpvoid);





DWORD WINAPI RecvSendThead(LPVOID lpvoid)

{

	timeval timeout = {3,0};

	

	while(TRUE)

	{

		DWORD ClientSockNum = gClientSockNum;

		if(ClientSockNum)

		{

			FD_SET readset;

			FD_ZERO (&readset);

			for(DWORD i=0;i<ClientSockNum;i++)

			{

				FD_SET(gClientSockAddr[i],&readset);

			}

			int ReadableNum = select(0,&readset,NULL,NULL,&timeout);

			

			if(ReadableNum == 0)

			{

				continue;

			}else{

				for(DWORD k = 0;k<ClientSockNum;k++)

				{

					if(FD_ISSET(gClientSockAddr[k],&readset))

					{

						char buf[MAX_PATH] = {0};

						int recvlen = recv(gClientSockAddr[k],buf,MAX_PATH,0);

						

						//if(strcmp(buf,"quit") == 0)

						if(strcmp(buf,"quit") == 0)

						{

							//断开

							shutdown(gClientSockAddr[k],SD_SEND);

							closesocket(gClientSockAddr[k]);

							WaitForSingleObject(ghMutex,INFINITE);

							gClientSockAddr[k] = gClientSockAddr[gClientSockNum-1];

							gClientSockAddr[gClientSockNum - 1] = NULL;

							gClientSockNum-=1;

							ReleaseMutex(ghMutex);

						}





						if(recvlen ==0 || recvlen == -1)

						{

							//断开

							shutdown(gClientSockAddr[k],SD_SEND);

							closesocket(gClientSockAddr[k]);

							WaitForSingleObject(ghMutex,INFINITE);

							gClientSockAddr[k] = gClientSockAddr[gClientSockNum-1];

							gClientSockAddr[gClientSockNum - 1] = NULL;

							gClientSockNum-=1;

							ReleaseMutex(ghMutex);

						}else{

							printf("Client Message: %s\n",buf);

							send(gClientSockAddr[k],buf,strlen(buf)+1,0);

							memset(buf,0,MAX_PATH);

						}



					}

				}

			}

		}

	}



	return 0;

}





int main(int argc, char* argv[])

{

	//0：初始化

	WORD wVersionRequested;

	WSADATA wsaData;

	int err;

	wVersionRequested = MAKEWORD( 2, 2 );

 

	err = WSAStartup( wVersionRequested, &wsaData );

	if ( err != 0 ) {

		/* Tell the user that we could not find a usable */

		/* WinSock DLL.                                  */

		return 0;

	}



	//1 create socket

	SOCKET hSerSocket = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);

	

	//2 bind

	struct sockaddr_in SerAddr={0};

	SerAddr.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");

	SerAddr.sin_family = AF_INET;

	SerAddr.sin_port = htons(2018);

	bind(hSerSocket,(sockaddr*)&SerAddr,sizeof(SerAddr));



	//3 listen

	listen(hSerSocket,5);



	//4 accept



	

	ghMutex = CreateMutex(NULL,FALSE,NULL);



	HANDLE hThread = CreateThread(NULL,0,RecvSendThead,NULL,0,NULL);

	CloseHandle(hThread);



	while(TRUE)

	{

		struct sockaddr ClientAddr={0};

		int ClientAddrLen = sizeof(sockaddr);

		SOCKET hClientSocket = accept(hSerSocket,(sockaddr*)&ClientAddr,&ClientAddrLen);



		WaitForSingleObject(ghMutex,INFINITE);

		gClientSockAddr[gClientSockNum++] = hClientSocket;

		printf("第 %d 个客户进来\n",gClientSockNum);

		ReleaseMutex(ghMutex);

	}

	//5 send recv

	

	closesocket(hSerSocket);	

	WSACleanup();

	

	

	return 0;

}

Client客户端

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

//



#include "stdafx.h"

#include <Winsock2.h>



#pragma comment(lib,"Ws2_32.lib")



int main(int argc, char* argv[])

{

	/*

	创建套接字

	绑定套接字

	连接服务器

	收发数据

	断开连接(主动)

	关闭套接字

	*/

	

	//0：初始化

	WORD wVersionRequested;

	WSADATA wsaData;

	int err;

	wVersionRequested = MAKEWORD( 2, 2 );

 

	err = WSAStartup( wVersionRequested, &wsaData );

	if ( err != 0 ) {

		/* Tell the user that we could not find a usable */

		/* WinSock DLL.                                  */

		return 0;

	}





	//1 create socket

	SOCKET hCliSocket = socket(AF_INET,SOCK_STREAM,IPPROTO_TCP);

	//2 connet

	struct sockaddr_in SerAddr={0};

	SerAddr.sin_addr.S_un.S_addr = inet_addr("127.0.0.1");

	SerAddr.sin_family = AF_INET;

	SerAddr.sin_port = htons(2018);

	

	connect(hCliSocket,(sockaddr*)&SerAddr,sizeof(SerAddr));

	//3 send/recv

	char sendBuf[100]={0};

	while(TRUE)

	{

		scanf("%s",&sendBuf);

		if(strcmp(sendBuf,"quit")==0)

		{

			break;

		}

		send(hCliSocket,sendBuf,strlen(sendBuf)+1,0);

		char recvBuf[100]={0};

		recv(hCliSocket,recvBuf,100,0);

		printf("client: %s\n",recvBuf);

		

	}

	

	

	shutdown(hCliSocket,SD_RECEIVE);

	closesocket(hCliSocket);

	

	return 0;

}