C/C++ socket 通信实现

服务器：

创建套接字(socket) -> 绑定IP(bind) -> 设置监听上限(listen)-> 开始接受(accept) -> 接收消息(recv) ->发送消息(send)

#include <iostream>
#include <string.h>
#include <WinSock2.h>
#include <errno.h>
#include <WS2tcpip.h>
#include <winsock.h>

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

using namespace std;

int main()
{
/*-----------vs2017  加载套接字库------------------------*/
	WSADATA wsaData;
	int iRet = 0;
	iRet = WSAStartup(MAKEWORD(2, 2), &wsaData);
	if (iRet != 0)
	{
		cout << "WSAStartup(MAKEWORD(2, 2), &wsaData) execute failed!" << endl;
		return -1;
	}
	if (2 != LOBYTE(wsaData.wVersion) || 2 != HIBYTE(wsaData.wVersion))
	{
		WSACleanup();
		cout << "WSADATA version is not correct!" << endl;
		return -1;
	}
/*-----------------------------------*/
	SOCKET server_sock, server_connect_sock;
	//创建套接字
	server_sock = socket(AF_INET,SOCK_STREAM,0);
	if (INVALID_SOCKET == server_sock)
	{
		cout << "socket create error!!!" << endl;
		return -1;
	}
	cout << "socket create success !!" << endl;
	//绑定IP地址
	struct sockaddr_in  server_addr;
	memset(&server_addr, 0, sizeof(server_addr));
	server_addr.sin_family = AF_INET;
	server_addr.sin_addr.S_un.S_addr= htonl(INADDR_ANY);
	server_addr.sin_port = htons(6000);
	if (SOCKET_ERROR == bind(server_sock, (sockaddr *)&server_addr, sizeof(sockaddr)))
	{
		cout << "bind error!!!" << endl;
		return -1;
	}
	cout << "bind success !!" << endl;

	//建立监听
	if (SOCKET_ERROR == listen(server_sock, 5))
	{
		cout << "listen fail" << endl;
		return -1;
	}
	cout << "listen successs" << endl;

	//开始接收
	struct sockaddr_in  client_addr;
	int len = sizeof(sockaddr);
	server_connect_sock = accept(server_sock, (sockaddr *)&client_addr, &len);
	if (INVALID_SOCKET == server_connect_sock)
	{
		cout << "accept  error !!" << endl;
	}
	int len;
	while (true)
	{
		char recvBuf[100];
		char sendBuf[100] = { "hello" };
		memset(recvBuf, 0, sizeof(recvBuf));

		len = recv(server_connect_sock, recvBuf, 100, 0);
		if(len <= 0)
		{
			break;
		}
		cout << "server recvs " << inet_ntoa(client_addr.sin_addr) << " : " << recvBuf << endl;

		//发送消息
		send(server_connect_sock, sendBuf, 100, 0);
	
	}
	cout << "OK" << endl;
	//清理
	closesocket(server_sock);
	closesocket(server_connect_sock);
	WSACleanup();
	return 0;
}

客户端

创建套接字(socket) -> 建立链接(connect)  ->发送消息(send) -> 接收消息(recv)

#include<iostream>
#include <winsock2.h>
#include <Ws2tcpip.h>

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

using namespace std;
int main()
{
	//加载套接字库
	WSADATA wsaData;
	int iRet = 0;
	iRet = WSAStartup(MAKEWORD(2, 2), &wsaData);
	if (iRet != 0)
	{
		cout << "WSAStartup(MAKEWORD(2, 2), &wsaData) execute failed!" << endl;
		return -1;
	}
	if (2 != LOBYTE(wsaData.wVersion) || 2 != HIBYTE(wsaData.wVersion))
	{
		WSACleanup();
		cout << "WSADATA version is not correct!" << endl;
		return -1;
	}

	//创建套接字
	SOCKET client_Socket = socket(AF_INET, SOCK_STREAM, 0);
	if (client_Socket == INVALID_SOCKET)
	{
		cout << "client_Socket create failed!" << endl;
		return -1;
	}
	cout << "client_Socket create success !! " << endl;
	
	//初始化服务器端地址族变量
	SOCKADDR_IN server_addr;
	inet_pton(AF_INET, "192.168.0.102", &server_addr.sin_addr);
	server_addr.sin_family = AF_INET;
	server_addr.sin_port = htons(6000);

	//连接服务器
	iRet = connect(client_Socket, (SOCKADDR*)&server_addr, sizeof(SOCKADDR));
	if (0 != iRet)
	{
		cout << "connect failed!" << endl;
		return -1;
	}
	cout << "connect success!" << endl;

	char sendBuf[100];
	char recvBuf[100];

	while (true)
	{
		memset(sendBuf, 0, sizeof(sendBuf));
		memset(recvBuf, 0, sizeof(recvBuf));
		
		//发送消息
		cout << "send：";
		cin >> sendBuf;
		send(client_Socket, sendBuf, strlen(sendBuf) + 1, 0);
		
		//接收消息
		recv(client_Socket, recvBuf, 100, 0);
		cout << "client recv : " << recvBuf << endl;
		
	}

	//清理
	closesocket(client_Socket);
	WSACleanup();
	return 0;
}

windows多线程服务器

#include <iostream>
#include <string.h>
#include <WinSock2.h>
#include <errno.h>
#include <WS2tcpip.h>
#include <winsock.h>
#include <thread>

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

using namespace std;

void doWork(SOCKET fd, struct sockaddr_in addr_client)
{
	cout << "doWork...." << fd << endl;
	char recvBuf[100];
	char sendBuf[100] = { "hello" };
	int len;
	while (true)
	{	
		
		memset(recvBuf, 0, sizeof(recvBuf));
		len = recv(fd, recvBuf, 100, 0);
		if (len <= 0)
		{
			cout << "用户：" << inet_ntoa(addr_client.sin_addr) << "  " << ntohs(addr_client.sin_port) << " 已退出！！ "  << endl;
			return;
		}
		cout << "server recvs " << inet_ntoa(addr_client.sin_addr) << "  " << ntohs(addr_client.sin_port) << " : " << recvBuf << endl;
		//发送消息
		send(fd, sendBuf, 100, 0);
	}
	return ;
}

int main()
{

	WSADATA wsaData;
	int iRet = 0;
	iRet = WSAStartup(MAKEWORD(2, 2), &wsaData);
	if (iRet != 0)
	{
		cout << "WSAStartup(MAKEWORD(2, 2), &wsaData) execute failed!" << endl;
		return -1;
	}
	if (2 != LOBYTE(wsaData.wVersion) || 2 != HIBYTE(wsaData.wVersion))
	{
		WSACleanup();
		cout << "WSADATA version is not correct!" << endl;
		return -1;
	}

	//创建套接字
	SOCKET lfd_serv, cfd_serv;
	lfd_serv = socket(AF_INET, SOCK_STREAM, 0);
	if (lfd_serv == INVALID_SOCKET)
	{
		cout << "create socket error!! " << endl;
		return -1;
	}

	//绑定IP和端口号
	struct sockaddr_in addr_serv;
	addr_serv.sin_family = AF_INET;
	addr_serv.sin_port = htons(6000);
	//addr_serv.sin_addr.S_un.S_addr = inet_addr("192.168.0.102");
	addr_serv.sin_addr.S_un.S_addr = htonl(INADDR_ANY);
	iRet = ::bind(lfd_serv,(sockaddr *)&addr_serv,sizeof(addr_serv));
	if (iRet == SOCKET_ERROR)
	{
		cout << "bind socket error!! " << endl;
		return -1;
	}

	//设置监听
	iRet = listen(lfd_serv, 5);
	if (iRet == SOCKET_ERROR)
	{
		cout << "listen socket error!! " << endl;
		return -1;
	}
	struct sockaddr_in addr_client;
	int len	 = sizeof(addr_client);;
	while (true)
	{
		//监听

		cfd_serv = accept(lfd_serv, (sockaddr *)&addr_client,&len );
		if (cfd_serv == INVALID_SOCKET)
		{
			cout << "accept error" << endl;
			return -1;
		}
		//创建子进程处理连接事件
	//CreateThread(NULL,0,doWork,NULL, cfd_serv,0);
		thread rst = thread(doWork, cfd_serv, addr_client);
		rst.detach();
		cout << "thread  run ..." << endl;
		//closesocket(cfd_serv);
		
	}

}