My sympathies re lack of responses on best IPC practices.  I've been watching
these posts hoping for some good ideas and a useful discussion.  No joy.

I've tried a few non-.net things, and I've found named pipes and WM_COPYDATA
to be the least offensive. Nothing in .net has satisfied me.  Remoting is/was
the way to go in recent times, but it looks like DCOM (ugh!) warmed over.  
WCF is next in line to save the day, but I don't know (I am at .net 2005 fw
2), and I am dubious.  I seem to recall reading about fw 3 or 3.5 providing
stream io for pipes, but I don't know anything about it.  Pipes are good for
point to point, but your situation sounds like you need a broadcast.

I want a .net equivalent of an activex exe.

"John Heitmuller." <john.heitmuller@jrfcorp.net> wrote in news:def2d542-
df79-497d-8c63-a95a5b9b76e0@u69g2000hse.googlegroups.com:

Which part of remoting are you having trouble with?

You could also use WCF as well, which is more or less remoting's
replacement.

Okay, since nobody took up my challenge.  I've had to solve this
myself.  I have written a simple but complete demo of inter-process
two-communication using named pipes implemented with version 3.5 of
the .Net Framework in VB.  The complete solution can be downloaded
from here.

http://mysite.verizon.net/johnheitmuller/TxtMsg.zip

I've included all of the VisualStudio 2008 run-time libs needed to run
this example even if you do not have VS2008 installed.

Here is the source listing.

Imports System.Text                     ' required for UTF8Encoding
Imports System.IO
Imports System.IO.Pipes

Public Class TxtMsg
   Private strPipeName As String
   Private encoding As UTF8Encoding
   Private pipeServer As NamedPipeServerStream
   Private Const nbrTimeOut As Integer = 5000    ' 5 seconds

   Private Sub TxtMsg_Load(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Load
       CheckForIllegalCrossThreadCalls = False     ' required for
running in debugger. ConnectionCallback() runs in s separate thread
       encoding = New UTF8Encoding()
       Me.strPipeName = Process.GetCurrentProcess.ProcessName & "_" &
Process.GetCurrentProcess.Id

       Me.UpdateStatus("Creating Named Pipe Server: " &
Me.strPipeName)
       pipeServer = New NamedPipeServerStream(Me.strPipeName,
PipeDirection.In, 1, PipeTransmissionMode.Message,
PipeOptions.Asynchronous)
       Me.UpdateStatus("Named Pipe Created.")

       pipeServer.BeginWaitForConnection(AddressOf
ConnectionCallback, Nothing)
       Me.UpdateStatus("Waiting for connection.")
   End Sub

   Private Sub btnSend_Click(ByVal sender As System.Object, ByVal e
As System.EventArgs) Handles btnSend.Click
       If Not String.IsNullOrEmpty(Me.tbxMessage.Text) Then
           Dim proc As Process = Process.GetCurrentProcess()
           Dim strTrgProcessName = proc.ProcessName
           If Me.cbxOtherInstanceInDebugger.Checked Then
strTrgProcessName &= ".vshost"
           Dim processes() As Process =
Process.GetProcessesByName(strTrgProcessName)
           If processes.Length > 0 Then
               Dim bytesMessage() As Byte =
encoding.GetBytes(Me.tbxMessage.Text & vbCrLf)
               Dim bytesProcID() As Byte =
encoding.GetBytes(proc.Id.ToString & vbCrLf)
               For Each p As Process In processes
                   If p.Id <> proc.Id Then ' don't send to self
                       Dim strServerPipeName As String =
p.ProcessName & "_" & p.Id

                       Me.UpdateStatus("Attempting to connect to
server " & strServerPipeName & ".  Timeout = " & nbrTimeOut.ToString &
" milliseconds.")
                       Dim pipeStream As NamedPipeClientStream = New
NamedPipeClientStream(".", strServerPipeName, PipeDirection.Out) '
"."=localhost
                       pipeStream.Connect(nbrTimeOut)
                       Me.UpdateStatus("Connection established.")

                       Me.UpdateStatus("Writing to server Proc ID: "
& proc.Id.ToString & ", Message: " & Me.tbxMessage.Text)
                       pipeStream.Write(bytesProcID, 0,
bytesProcID.Length)
                       pipeStream.Write(bytesMessage, 0,
bytesMessage.Length)
                       Me.tbxConversation.Text &=
DateTime.Now.ToLongTimeString() & ":  " & proc.Id & "  " &
Me.tbxMessage.Text & vbCrLf
                       Me.tbxMessage.Clear()
                       Me.UpdateStatus("Closing connection...")
                       pipeStream.Close()
                       Me.UpdateStatus("Connection closed.")
                   End If
               Next ' next process
           End If
       End If
   End Sub

   Private Sub ConnectionCallback(ByVal ar As IAsyncResult)
       Me.UpdateStatus("ConnectionCallback() fired.")
       Me.pipeServer.EndWaitForConnection(ar)
       Me.UpdateStatus("End Waiting for Connection.")

       Dim sr As StreamReader = New StreamReader(Me.pipeServer)
       Dim strProcID As String = sr.ReadLine()
       Dim strMessage As String = sr.ReadLine()
       Me.UpdateStatus("Received ProcID String (" & strProcID & "),
string length = " & strProcID.Length.ToString)
       Me.UpdateStatus("Received Message String (" & strMessage & "),
string length = " & strMessage.Length.ToString)
       Me.tbxConversation.Text &= DateTime.Now.ToLongTimeString() &
":  " & strProcID & "  " & strMessage & vbCrLf

       Me.UpdateStatus("Disconnecting connection.")
       Me.pipeServer.Disconnect()
       pipeServer.BeginWaitForConnection(AddressOf
ConnectionCallback, Nothing)
       Me.UpdateStatus("Waiting for connection.")
   End Sub

   Private Sub UpdateStatus(ByRef str As String)
       Me.tbxStatus.AppendText(DateTime.Now.ToLongTimeString() & ":
" & str & vbCrLf)
   End Sub
End Class