BUG: CallNamedPipe() API lpBytesRead Parameter Returns Bogus Number

ID: Q235717

The information in this article applies to:

Microsoft Windows 98
on the following platforms: Win98
Microsoft Windows 98 Second Edition

SYMPTOMS

When you use the CallNamedPipe() API on Windows 98 to communicate to a message-based Named Pipe on a Windows NT computer, the lpBytesRead parameter which specifies the actual amount of bytes written into the read buffer lpOutBuffer returns a number, which does not reflect the amount of bytes in the buffer. This number is typically a very large number. It should be noted though, that the read buffer will still contain the received data on a successful call.

CAUSE

The SMB used for the named pipe is read incorrectly by Windows 98 for the CallNamedPipe() API.

RESOLUTION

If the number of bytes written lpBytesRead into the read buffer is required, a traditional CreateFile()/WriteFile()/ReadFile() sequence of using a named pipe or the TransactNamedPipe() API can be used. Alternatively, the following code can be used to mimic the behavior of the CallNamedPipe() API:


BOOL MimicCallNamedPipe(
  LPCTSTR lpNamedPipeName,  // pointer to pipe name
  LPVOID lpInBuffer,        // pointer to write buffer
  DWORD nInBufferSize,      // size, in bytes, of write buffer
  LPVOID lpOutBuffer,       // pointer to read buffer
  DWORD nOutBufferSize,     // size, in bytes, of read buffer
  LPDWORD lpBytesRead,      // pointer to number of bytes read
  DWORD nTimeOut            // time-out value, in milliseconds
)
{
  HANDLE hPipe = INVALID_HANDLE_VALUE;
  DWORD dwPipeMode = PIPE_READMODE_MESSAGE | PIPE_WAIT;

  if (WaitNamedPipe(lpNamedPipeName, nTimeOut) == FALSE)
    return FALSE;

  hPipe = CreateFile(lpNamedPipeName, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
  if (hPipe == INVALID_HANDLE_VALUE)
    return FALSE;
      
  if (SetNamedPipeHandleState(hPipe, &dwPipeMode, NULL, NULL) == FALSE)
    return FALSE;
    
  if (TransactNamedPipe(hPipe, lpInBuffer, nInBufferSize, lpOutBuffer, nOutBufferSize, lpBytesRead, NULL) == FALSE)
    return FALSE;

  CloseHandle(hPipe);

  return TRUE;
}

Microsoft provides programming examples for illustration only, without warranty either expressed or implied, including, but not limited to, the implied warranties of merchantability and/or fitness for a particular purpose. This article assumes that you are familiar with the programming language being demonstrated and the tools used to create and debug procedures. Microsoft support professionals can help explain the functionality of a particular procedure, but they will not modify these examples to provide added functionality or construct procedures to meet your specific needs. If you have limited programming experience, you may want to contact a Microsoft Certified Solution Provider or the Microsoft fee-based consulting line at (800) 936-5200. For more information about Microsoft Certified Solution Providers, please see the following page on the World Wide Web:

http://www.microsoft.com/mcsp/

For more information about the support options available from Microsoft, please see the following page on the World Wide Web:

http://www.microsoft.com/support/supportnet/overview/overview.asp

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article.

REFERENCES

Please see the latest Platform SDK for more information on Named Pipes.

Additional query words:

Keywords : kbnetwork kbAPI kbIPC kbPipes kbSDKPlatform kbSDKWin32 kbWinOS98bug kbDSupport kbGrpNet
Version : WINDOWS:
Platform : WINDOWS
Issue type : kbbug