如何编写简单的端口扫描程序：

如何编写最简单的端口扫描程序：

一：新建一个支持MFC的WIN32控制台应用程序；二：在 SCANPORT.CPP文件中，添加两个全局变量：       int i ;       CSocket sockClient;              再添加线程处理函数定义：               DWORD WINAPI ScanPorts(LPVOID);

 int _tmain(int argc, TCHAR* argv[], TCHAR* envp[])代码如下：

int _tmain(int argc, TCHAR* argv[], TCHAR* envp[]){ int nRetCode = 0;  // initialize MFC and print and error on failure if (!AfxWinInit(::GetModuleHandle(NULL), NULL, ::GetCommandLine(), 0)) {  // TODO: change error code to suit your needs  cerr << _T("Fatal Error: MFC initialization failed") << endl;  nRetCode = 1; } else {  ::SetConsoleTitle("Scan ports -- Written by CodeWorrior");  

///// 扫描的主机，可以改为用户输入////  // TODO: code your application's behavior here.  AfxSocketInit(NULL);

  for(i=1;i<=10;i++)  {   HANDLE hThread;   DWORD dwThreadID;     file://cout<<i<<endl;   hThread = CreateThread(NULL,0,ScanPorts,(LPVOID)i,0,&dwThreadID);   Sleep(1000);   ::WaitForSingleObject(hThread,200);   CloseHandle(hThread);  }   } cout<<endl; return nRetCode;}

DWORD WINAPI ScanPorts(LPVOID p){  try {   int j = (i-1)*100;  printf("Thread %d starting/n",i);  for(j;j<i*100;j++)  {     sockClient.Create();      if(sockClient.Connect("10.128.0.3",1028))   {    cout<<endl;    cout<<"port"<<"  "<<j<<"   ";    cout<<"Connect to server succeed!"<<endl;;    sockClient.Close();   }   else   {     printf("port %d connect to server failed/n",j);      //可以显示正在连接那个端口     sockClient.Close();   }  } } catch(...) {  sockClient.Close(); } printf("Thread %d Terminate!/n",i); return 0;}