Двунаправленный PIPE: как реализовать двунаправленную связь?

HANDLE hPipe;
   LPTSTR lpszWrite = TEXT("Default message from client");
   TCHAR chReadBuf[BUFSIZE];
   BOOL fSuccess;
   DWORD cbRead, dwMode;
   LPTSTR lpszPipename = TEXT("\\\\.\\pipe\\tst");
 
   // Try to open a named pipe; wait for it, if necessary. 
   while (1)
   {
       hPipe = CreateFile(
           lpszPipename,   // pipe name 
           GENERIC_READ |  // read and write access 
           GENERIC_WRITE,
           0,              // no sharing 
           NULL,           // default security attributes
           OPEN_EXISTING,  // opens existing pipe 
           0,              // default attributes 
           NULL);          // no template file 
 
                           // Break if the pipe handle is valid. 
       if (hPipe != INVALID_HANDLE_VALUE)
           break;
 
       // Exit if an error other than ERROR_PIPE_BUSY occurs. 
       if (GetLastError() != ERROR_PIPE_BUSY)
       {
           printf("Could not open pipe\n");
           return 0;
       }
 
       // All pipe instances are busy, so wait for 20 seconds. 
       if (!WaitNamedPipe(lpszPipename, 20000))
       {
           printf("Could not open pipe\n");
           return 0;
       }
   }
 
   // The pipe connected; change to message-read mode. 
   dwMode = PIPE_READMODE_MESSAGE;
   fSuccess = SetNamedPipeHandleState(
       hPipe,    // pipe handle 
       &dwMode,  // new pipe mode 
       NULL,     // don't set maximum bytes 
       NULL);    // don't set maximum time 
   if (!fSuccess)
   {
       printf("SetNamedPipeHandleState failed.\n");
       return 0;
   }
 
   // Read from the pipe if there is more data in the message.
   fSuccess = ReadFile(
       hPipe,      // pipe handle 
       chReadBuf,  // buffer to receive reply 
       BUFSIZE*sizeof(TCHAR),  // size of buffer 
       &cbRead,  // number of bytes read 
       NULL);    // not overlapped 
 
                 // Exit if an error other than ERROR_MORE_DATA occurs.
   if (!fSuccess && (GetLastError() != ERROR_MORE_DATA))
       printf("====== read bad ==========\n");
   else {
       printf("====== read ok ==========\n");
       _tprintf(TEXT("%s\n"), chReadBuf);
   }
 
 
 
   // Send a message to the pipe server and read the response. 
   printf("====== sending... ==========\n");
   fSuccess = TransactNamedPipe(//---------------------- функция "зависает"
       hPipe,                  // pipe handle 
       lpszWrite,              // message to server
       (lstrlen(lpszWrite) + 1)*sizeof(TCHAR), // message length 
       chReadBuf,              // buffer to receive reply
       BUFSIZE*sizeof(TCHAR),  // size of read buffer
       &cbRead,                // bytes read
       NULL);                  // not overlapped 
 
   printf("\n===== send ok ============\n")//--------------- сюда не попадаем
 
   if (!fSuccess && (GetLastError() != ERROR_MORE_DATA))
   {
       printf("====== error send ==========...\n");
       return 0;
   }
 
   printf("====== END ==========...\n");