RE: 231 - All pipe instances are busy when connecting a pipe

I've just been investigating a similar problem today. Similar in that I'm
getting 231 on my named pipe clients, different in that I've written the
client and server using .NET and have not yet added the overlapped stuff in
yet.

At any rate, my server would create a named pipe and wait for a connection.
After sending a couple messages to the client the communication was over and
it would disconnect the client and try connecting another client. This all
worked fine when I ran the client one at a time and the client just had this
one conversation. I then wanted to see how many conversations I could have
per second. I simply added a 1 to 100 loop in the client and once I did that
most of the requests failed. I attributed this to the client being ready to
open the file (pipe) again before the server go around to trying to
reconnect. By the way, I'm running this on my single processor laptop.

I figured I could fix this by creating two of the server threads which
create the pipe and communicate with the client. Surprisingly this didn't
fix the problem. My thought was that if the thread which was communicating
with the client was still shutting down things and had not looped around to
ConnectNamedPipe() that the other thread would have its pipe available for
the connection. Not sure why the two thread solution didn't fix the problem,
but again I'm running on a single processor laptop and multi-threaded issues
behave oddly.

After reading some posts it was suggested that I call WaitNamePipe() in the
client. I added that call if the first call to CreateFile() fails and this
seems to have resolved my problem. Code snippet:

..
..
..
pipe = Win32.File.CreateFile(pipeName,
      Win32.File.GENERIC_READ | Win32.File.GENERIC_WRITE,
      0, null, Win32.File.OPEN_EXISTING, 0, IntPtr.Zero);
if (pipe == Win32.File.INVALID_HANDLE_VALUE)
   {
   if (Marshal.GetLastWin32Error() == Win32.NamedPipe.ERROR_PIPE_BUSY)
      {
      if (Win32.NamedPipe.WaitNamedPipe(pipeName, 20) != 0)
         {
         pipe = Win32.File.CreateFile(pipeName,
               Win32.File.GENERIC_READ | Win32.File.GENERIC_WRITE,
               0, null, Win32.File.OPEN_EXISTING, 0, IntPtr.Zero);
         }
      }
   }

if (pipe == Win32.File.INVALID_HANDLE_VALUE)
   Console.WriteLine("Error opening pipe, result = {0}",
Marshal.GetLastWin32Error());
else
   {
   .
   .
   .
--
Thanks,
Nick

nicknospamdu@community.nospam
remove "nospam" change community. to msn.com