_beginthreadex函數(shù)原型_ACRTIMP uintptr_t __cdecl _beginthreadex( _In_opt_ void* _Security,//安全屬性，NULL為默認安全屬性 _In_ unsigned _StackSize,//線程堆棧的大小。如果為0，則線程堆棧大小和創(chuàng)建它的線程的相同。一般用0  _In_ _beginthreadex_proc_type _StartAddress, //線程函數(shù)的地址 _In_opt_ void* _ArgList, //傳進線程的函數(shù) _In_ unsigned _InitFlag, //線程初始狀態(tài)，0:立即運行；CREATE_SUSPEND：懸掛（如果出事狀態(tài)定義為懸掛，就要調(diào)用ResumeThread(HANDLE) 來激活線程的運行）  _Out_opt_ unsigned* _ThrdAddr //用于記錄線程ID的地址 )

#include <process.h>#include <stdio.h>unsigned __stdcall Thread(void* param){  printf("%d/n", *(int*)param); //這里必須先要強行轉(zhuǎn)換為int*，不然void* 直接解引用會出錯。  return 0;}int main(){  int i = 0;  _beginthreadex(NULL, 0, Thread, &i, 0, NULL);  return 0;}

#include <WinSock2.h>#include <process.h>#include <stdio.h>#include <stdlib.h>#pragma comment(lib,"ws2_32.lib")#define SEND_OVER 1             //已經(jīng)轉(zhuǎn)發(fā)消息#define SEND_YET 0             //還沒轉(zhuǎn)發(fā)消息int g_iStatus = SEND_YET;SOCKET g_ServerSocket = INVALID_SOCKET;   //服務(wù)端套接字SOCKADDR_IN g_ClientAddr = { 0 };      //客戶端地址int g_iClientAddrLen = sizeof(g_ClientAddr);bool g_bCheckConnect = false;        //檢查連接情況HANDLE g_hRecv1 = NULL;HANDLE g_hRecv2 = NULL;//客戶端信息結(jié)構(gòu)體typedef struct _Client{  SOCKET sClient;   //客戶端套接字  char buf[128];    //數(shù)據(jù)緩沖區(qū)  char userName[16];  //客戶端用戶名  char IP[20];     //客戶端IP  UINT_PTR flag;    //標記客戶端，用來區(qū)分不同的客戶端}Client;Client g_Client[2] = { 0 };         //創(chuàng)建一個客戶端結(jié)構(gòu)體//發(fā)送數(shù)據(jù)線程unsigned __stdcall ThreadSend(void* param){  int ret = 0;  int flag = *(int*)param;  SOCKET client = INVALID_SOCKET;         //創(chuàng)建一個臨時套接字來存放要轉(zhuǎn)發(fā)的客戶端套接字  char temp[128] = { 0 };             //創(chuàng)建一個臨時的數(shù)據(jù)緩沖區(qū)，用來存放接收到的數(shù)據(jù)  memcpy(temp, g_Client[!flag].buf, sizeof(temp));  sprintf(g_Client[flag].buf, "%s: %s", g_Client[!flag].userName, temp);//添加一個用戶名頭  if (strlen(temp) != 0 && g_iStatus == SEND_YET) //如果數(shù)據(jù)不為空且還沒轉(zhuǎn)發(fā)則轉(zhuǎn)發(fā)    ret = send(g_Client[flag].sClient, g_Client[flag].buf, sizeof(g_Client[flag].buf), 0);  if (ret == SOCKET_ERROR)    return 1;  g_iStatus = SEND_OVER;  //轉(zhuǎn)發(fā)成功后設(shè)置狀態(tài)為已轉(zhuǎn)發(fā)  return 0;}//接受數(shù)據(jù)unsigned __stdcall ThreadRecv(void* param){  SOCKET client = INVALID_SOCKET;  int flag = 0;   if (*(int*)param == g_Client[0].flag)      //判斷是哪個客戶端發(fā)來的消息  {    client = g_Client[0].sClient;    flag = 0;  }    else if (*(int*)param == g_Client[1].flag)  {    client = g_Client[1].sClient;    flag = 1;  }  char temp[128] = { 0 }; //臨時數(shù)據(jù)緩沖區(qū)  while (1)  {    memset(temp, 0, sizeof(temp));    int ret = recv(client, temp, sizeof(temp), 0); //接收數(shù)據(jù)    if (ret == SOCKET_ERROR)      continue;    g_iStatus = SEND_YET;                //設(shè)置轉(zhuǎn)發(fā)狀態(tài)為未轉(zhuǎn)發(fā)    flag = client == g_Client[0].sClient ? 1 : 0;    //這個要設(shè)置，否則會出現(xiàn)自己給自己發(fā)消息的BUG    memcpy(g_Client[!flag].buf, temp, sizeof(g_Client[!flag].buf));    _beginthreadex(NULL, 0, ThreadSend, &flag, 0, NULL); //開啟一個轉(zhuǎn)發(fā)線程,flag標記著要轉(zhuǎn)發(fā)給哪個客戶端    //這里也可能是導致CPU使用率上升的原因。  }  return 0;}//管理連接unsigned __stdcall ThreadManager(void* param){  while (1)  {    if (send(g_Client[0].sClient, "", sizeof(""), 0) == SOCKET_ERROR)    {      if (g_Client[0].sClient != 0)      {        CloseHandle(g_hRecv1); //這里關(guān)閉了線程句柄，但是測試結(jié)果斷開連C/S接后CPU仍然瘋漲        CloseHandle(g_hRecv2);        printf("Disconnect from IP: %s,UserName: %s/n", g_Client[0].IP, g_Client[0].userName);        closesocket(g_Client[0].sClient);  //這里簡單的判斷：若發(fā)送消息失敗，則認為連接中斷(其原因有多種)，關(guān)閉該套接字        g_Client[0] = { 0 };      }    }    if (send(g_Client[1].sClient, "", sizeof(""), 0) == SOCKET_ERROR)    {      if (g_Client[1].sClient != 0)      {        CloseHandle(g_hRecv1);        CloseHandle(g_hRecv2);        printf("Disconnect from IP: %s,UserName: %s/n", g_Client[1].IP, g_Client[1].userName);        closesocket(g_Client[1].sClient);        g_Client[1] = { 0 };      }    }    Sleep(2000); //2s檢查一次  }  return 0;}//接受請求unsigned __stdcall ThreadAccept(void* param){  int i = 0;  int temp1 = 0, temp2 = 0;  _beginthreadex(NULL, 0, ThreadManager, NULL, 0, NULL);  while (1)  {    while (i < 2)    {      if (g_Client[i].flag != 0)      {        ++i;        continue;      }      //如果有客戶端申請連接就接受連接      if ((g_Client[i].sClient = accept(g_ServerSocket, (SOCKADDR*)&g_ClientAddr, &g_iClientAddrLen)) == INVALID_SOCKET)      {        printf("accept failed with error code: %d/n", WSAGetLastError());        closesocket(g_ServerSocket);        WSACleanup();        return -1;      }      recv(g_Client[i].sClient, g_Client[i].userName, sizeof(g_Client[i].userName), 0); //接收用戶名      printf("Successfuuly got a connection from IP:%s ,Port: %d,UerName: %s/n",        inet_ntoa(g_ClientAddr.sin_addr), htons(g_ClientAddr.sin_port), g_Client[i].userName);      memcpy(g_Client[i].IP, inet_ntoa(g_ClientAddr.sin_addr), sizeof(g_Client[i].IP)); //記錄客戶端IP      g_Client[i].flag = g_Client[i].sClient; //不同的socke有不同UINT_PTR類型的數(shù)字來標識      i++;    }    i = 0;    if (g_Client[0].flag != 0 && g_Client[1].flag != 0)         //當兩個用戶都連接上服務(wù)器后才進行消息轉(zhuǎn)發(fā)    {      if (g_Client[0].flag != temp1)   //每次斷開一個連接后再次連上會新開一個線程，導致cpu使用率上升,所以要關(guān)掉舊的      {        if (g_hRecv1)         //這里關(guān)閉了線程句柄，但是測試結(jié)果斷開連C/S接后CPU仍然瘋漲          CloseHandle(g_hRecv1);        g_hRecv1 = (HANDLE)_beginthreadex(NULL, 0, ThreadRecv, &g_Client[0].flag, 0, NULL); //開啟2個接收消息的線程      }        if (g_Client[1].flag != temp2)      {        if (g_hRecv2)          CloseHandle(g_hRecv2);        g_hRecv2 = (HANDLE)_beginthreadex(NULL, 0, ThreadRecv, &g_Client[1].flag, 0, NULL);      }        }    temp1 = g_Client[0].flag; //防止ThreadRecv線程多次開啟    temp2 = g_Client[1].flag;    Sleep(3000);  }  return 0;}//啟動服務(wù)器int StartServer(){  //存放套接字信息的結(jié)構(gòu)  WSADATA wsaData = { 0 };  SOCKADDR_IN ServerAddr = { 0 };       //服務(wù)端地址  USHORT uPort = 18000;            //服務(wù)器監(jiān)聽端口  //初始化套接字  if (WSAStartup(MAKEWORD(2, 2), &wsaData))  {    printf("WSAStartup failed with error code: %d/n", WSAGetLastError());    return -1;  }  //判斷版本  if (LOBYTE(wsaData.wVersion) != 2 || HIBYTE(wsaData.wVersion) != 2)  {    printf("wVersion was not 2.2/n");    return -1;  }  //創(chuàng)建套接字  g_ServerSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);  if (g_ServerSocket == INVALID_SOCKET)  {    printf("socket failed with error code: %d/n", WSAGetLastError());    return -1;  }  //設(shè)置服務(wù)器地址  ServerAddr.sin_family = AF_INET;//連接方式  ServerAddr.sin_port = htons(uPort);//服務(wù)器監(jiān)聽端口  ServerAddr.sin_addr.S_un.S_addr = htonl(INADDR_ANY);//任何客戶端都能連接這個服務(wù)器  //綁定服務(wù)器  if (SOCKET_ERROR == bind(g_ServerSocket, (SOCKADDR*)&ServerAddr, sizeof(ServerAddr)))  {    printf("bind failed with error code: %d/n", WSAGetLastError());    closesocket(g_ServerSocket);    return -1;  }  //設(shè)置監(jiān)聽客戶端連接數(shù)  if (SOCKET_ERROR == listen(g_ServerSocket, 20000))  {    printf("listen failed with error code: %d/n", WSAGetLastError());    closesocket(g_ServerSocket);    WSACleanup();    return -1;  }  _beginthreadex(NULL, 0, ThreadAccept, NULL, 0, 0);  for (int k = 0;k < 100;k++) //讓主線程休眠，不讓它關(guān)閉TCP連接.    Sleep(10000000);  //關(guān)閉套接字  for (int j = 0;j < 2;j++)  {    if (g_Client[j].sClient != INVALID_SOCKET)      closesocket(g_Client[j].sClient);  }  closesocket(g_ServerSocket);  WSACleanup();  return 0;}int main(){  StartServer(); //啟動服務(wù)器  return 0;}

#define _WINSOCK_DEPRECATED_NO_WARNINGS#include <WinSock2.h>#include <process.h>#include <stdio.h>#include <stdlib.h>#include <conio.h>#pragma comment(lib,"ws2_32.lib")#define RECV_OVER 1#define RECV_YET 0char userName[16] = { 0 };int iStatus = RECV_YET;//接受數(shù)據(jù)unsigned __stdcall ThreadRecv(void* param){  char buf[128] = { 0 };  while (1)  {    int ret = recv(*(SOCKET*)param, buf, sizeof(buf), 0);    if (ret == SOCKET_ERROR)    {      Sleep(500);      continue;    }    if (strlen(buf) != 0)    {      printf("%s/n", buf);      iStatus = RECV_OVER;    }    else      Sleep(100);    }  return 0;}//發(fā)送數(shù)據(jù)unsigned __stdcall ThreadSend(void* param){  char buf[128] = { 0 };  int ret = 0;  while (1)  {    int c = getch();    if(c == 72 || c == 0 || c == 68)//為了顯示美觀，加一個無回顯的讀取字符函數(shù)      continue;          //getch返回值我是經(jīng)過實驗得出如果是返回這幾個值，則getch就會自動跳過，具體我也不懂。    printf("%s: ", userName);    gets_s(buf);    ret = send(*(SOCKET*)param, buf, sizeof(buf), 0);    if (ret == SOCKET_ERROR)      return 1;  }  return 0;}//連接服務(wù)器int ConnectServer(){  WSADATA wsaData = { 0 };//存放套接字信息  SOCKET ClientSocket = INVALID_SOCKET;//客戶端套接字  SOCKADDR_IN ServerAddr = { 0 };//服務(wù)端地址  USHORT uPort = 18000;//服務(wù)端端口             //初始化套接字  if (WSAStartup(MAKEWORD(2, 2), &wsaData))  {    printf("WSAStartup failed with error code: %d/n", WSAGetLastError());    return -1;  }  //判斷套接字版本  if (LOBYTE(wsaData.wVersion) != 2 || HIBYTE(wsaData.wVersion) != 2)  {    printf("wVersion was not 2.2/n");    return -1;  }  //創(chuàng)建套接字  ClientSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);  if (ClientSocket == INVALID_SOCKET)  {    printf("socket failed with error code: %d/n", WSAGetLastError());    return -1;  }  //輸入服務(wù)器IP  printf("Please input server IP:");  char IP[32] = { 0 };  gets_s(IP);  //設(shè)置服務(wù)器地址  ServerAddr.sin_family = AF_INET;  ServerAddr.sin_port = htons(uPort);//服務(wù)器端口  ServerAddr.sin_addr.S_un.S_addr = inet_addr(IP);//服務(wù)器地址  printf("connecting....../n");  //連接服務(wù)器  if (SOCKET_ERROR == connect(ClientSocket, (SOCKADDR*)&ServerAddr, sizeof(ServerAddr)))  {    printf("connect failed with error code: %d/n", WSAGetLastError());    closesocket(ClientSocket);    WSACleanup();    return -1;  }  printf("Connecting server successfully IP:%s Port:%d/n",    IP, htons(ServerAddr.sin_port));  printf("Please input your UserName: ");  gets_s(userName);  send(ClientSocket, userName, sizeof(userName), 0);  printf("/n/n");  _beginthreadex(NULL, 0, ThreadRecv, &ClientSocket, 0, NULL); //啟動接收和發(fā)送消息線程  _beginthreadex(NULL, 0, ThreadSend, &ClientSocket, 0, NULL);  for (int k = 0;k < 1000;k++)    Sleep(10000000);  closesocket(ClientSocket);  WSACleanup();  return 0;}int main(){  ConnectServer(); //連接服務(wù)器  return 0;}