named pipe between csharp and c++

Question

I have two projects: one runs on c++ and one runs on c-sharp. For some reason, when I try c++ to C++ server and client works fine, same if I tried c=sharp and c-sharp, The problem comes when I try C-sharp with c++. Here is the server code in c-sharp:

using System;
using System.IO;
using System.IO.Pipes;

class PipeServer
{
    static void Main()
    {
        using (NamedPipeServerStream pipeServer =
            new NamedPipeServerStream("\\\\.\\pipe\\mypipe", PipeDirection.Out))
        {
            Console.WriteLine("NamedPipeServerStream object created.");

            // Wait for a client to connect
            Console.Write("Waiting for client connection...");
            pipeServer.WaitForConnection();

            Console.WriteLine("Client connected.");
            try
            {
                // Read user input and send that to the client process. 
                using (StreamWriter sw = new StreamWriter(pipeServer))
                {
                    sw.AutoFlush = true;
                    Console.Write("Enter text: ");
                    sw.WriteLine(Console.ReadLine());
                }
            }
            // Catch the IOException that is raised if the pipe is broken 
            // or disconnected. 
            catch (IOException e)
            {
                Console.WriteLine("ERROR: {0}", e.Message);
            }
        }
    }
}

And Here is the client code in c++:

#include "stdafx.h"
#include <windows.h> 
#include <stdio.h>
#include <conio.h>
#include <tchar.h>

#define BUFSIZE 512

int _tmain(int argc, _TCHAR* argv[])
{
    HANDLE hPipe; 
   LPTSTR lpvMessage=TEXT("MSR"); 
   TCHAR  chBuf[BUFSIZE]; 
   BOOL   fSuccess = FALSE; 
   DWORD  cbRead, cbToWrite, cbWritten, dwMode; 
   LPTSTR lpszPipename = TEXT("\\\\.\\pipe\\mypipe"); 

   if( argc > 1 )
      lpvMessage = argv[1];

// 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) 
      {
         _tprintf( TEXT("Could not open pipe. GLE=%d\n"), GetLastError() ); 
         return -1;
      }

      // All pipe instances are busy, so wait for 20 seconds. 

      if ( ! WaitNamedPipe(lpszPipename, 20000)) 
      { 
         printf("Could not open pipe: 20 second wait timed out."); 
         return -1;
      } 
   } 

// 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) 
   {
      _tprintf( TEXT("SetNamedPipeHandleState failed. GLE=%d\n"), GetLastError() ); 
      return -1;
   }

// Send a message to the pipe server. 

   cbToWrite = (lstrlen(lpvMessage)+1)*sizeof(TCHAR);
   _tprintf( TEXT("Sending %d byte message: \"%s\"\n"), cbToWrite, lpvMessage); 

   fSuccess = WriteFile( 
      hPipe,                  // pipe handle 
      lpvMessage,             // message 
      cbToWrite,              // message length 
      &cbWritten,             // bytes written 
      NULL);                  // not overlapped 

   if ( ! fSuccess) 
   {
      _tprintf( TEXT("WriteFile to pipe failed. GLE=%d\n"), GetLastError() ); 
      return -1;
   }

   printf("\nMessage sent to server, receiving reply as follows:\n");

   do 
   { 
   // Read from the pipe. 

      fSuccess = ReadFile( 
         hPipe,    // pipe handle 
         chBuf,    // buffer to receive reply 
         BUFSIZE*sizeof(TCHAR),  // size of buffer 
         &cbRead,  // number of bytes read 
         NULL);    // not overlapped 

      if ( ! fSuccess && GetLastError() != ERROR_MORE_DATA )
         break; 

      _tprintf( TEXT("\"%s\"\n"), chBuf ); 
   } while ( ! fSuccess);  // repeat loop if ERROR_MORE_DATA 

   if ( ! fSuccess)
   {
      _tprintf( TEXT("ReadFile from pipe failed. GLE=%d\n"), GetLastError() );
      return -1;
   }

   //printf("\n<End of message, press ENTER to terminate connection and exit>");
   //_getch();

   CloseHandle(hPipe); 
    return 0;
}

When the client tries to connect to the server it returns with error code 2, which means file does not exist.

Answer 1

I had the same problem, but server is reader and client is writer. I just changed pipename in c# to "mypipe" and it worked.