Why doesn't my NamedPipeServerStream wait??
- by Frank Fella
I'm working with a NamedPipeServerStream to communicate between two processes. Here is the code where I initialize and connect the pipe:
void Foo(IHasData objectProvider)
{
Stream stream = objectProvider.GetData();
if (stream.Length > 0)
{
using (NamedPipeServerStream pipeServer = new NamedPipeServerStream("VisualizerPipe", PipeDirection.Out, 1, PipeTransmissionMode.Byte, PipeOptions.Asynchronous))
{
string currentDirectory = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
string uiFileName = Path.Combine(currentDirectory, "VisualizerUIApplication.exe");
Process.Start(uiFileName);
if(pipeServer.BeginWaitForConnection(PipeConnected, this).AsyncWaitHandle.WaitOne(5000))
{
while (stream.CanRead)
{
pipeServer.WriteByte((byte)stream.ReadByte());
}
}
else
{
throw new TimeoutException("Pipe connection to UI process timed out.");
}
}
}
}
private void PipeConnected(IAsyncResult e)
{
}
But it never seems to wait. I constantly get the following exception:
System.InvalidOperationException: Pipe hasn't been connected yet.
at System.IO.Pipes.PipeStream.CheckWriteOperations()
at System.IO.Pipes.PipeStream.WriteByte(Byte value)
at PeachesObjectVisualizer.Visualizer.Show(IDialogVisualizerService windowService, IVisualizerObjectProvider objectProvider)
I would think that after the wait returns everything should be ready to go.
If I use pipeServer.WaitForConnection() everything works fine, but hanging the application if the pipe doesn't connect is not an option.
