[RESOLVED] Using Namedpipes In 2008 vb .net - peek is hanging

[rknelsen]

Creating an application that uses both namedpipes and TCPIP connectivity to pass data between 2 legacy applications.
When there is actual data to pass everything works great. But when the application is looking to see if there is any data to read from the named pipe side and there is no data, the Peek hangs until there is data. Is there a problem in the way I have it coded or is there a timeout that needs to be set?

'
' declarations
'
     Private in_pipeName As String
     Private out_pipeName As String
     Private dwMode, cbRead As Long
     Private blnRecvPipeConnected As Boolean
     Private blnSendPipeConnected As Boolean
     Private blnRecvPortConnected As Boolean
     Private blnSendPortConnected As Boolean
     Private myTcpListener As TcpListener
     Private mySTcpListener As TcpListener
     Private myNetworkStream As NetworkStream
     Private mySocket As TcpClient
     Private mySocketSend As TcpClient
     Private SocketStream As NetworkStream
     Private ResponseStr As String = ""
     Private bArray(BUFFSIZE) As Byte
     Private sckin As Socket
     Private namedpipe_out As NamedPipeClientStream
     Private namedpipe_in As NamedPipeClientStream
     Private fSuccess As Boolean
     Public pipe_read_process As PipeStream
     Private pipe_readmode As PipeTransmissionMode
     Public pipe_write_process As PipeStream
 '
 ' main processing function
 '
 Private Sub connections()
 '
 ' connect named pipe connections to gateway
 '
 	connecttopipenet()
        
        Dim pipe_write_process As New StreamWriter(namedpipe_out)
        Dim pipe_read_process As New StreamReader(namedpipe_in)

'
' connect TcpIP connections 
'
        connecttotcp()

'
' main processing loop
'
        While True
            sleep(1000)

            Try
                If (blnRecvPortConnected = True) And (blnSendPipeConnected = True) And (blnRecvPipeConnected = True) And (blnSendPortConnected = True) Then
                    
                    sckin = mySocket.Client
                    
'
' check to make sure that TCPIP port is available
'
                    If sckin.Poll(1, SelectMode.SelectRead) = False Then
                        
                        RecordInfo(String.Concat("Still Connected"), EventLogEntryType.Information, 10003)
                    
                    ElseIf sckin.Poll(1, SelectMode.SelectRead) Then
                    
                    	RecordInfo(String.Concat("Lost Connected"), EventLogEntryType.Information, 10003)
                    
                    End If
                    
                    
                    SocketStream = mySocket.GetStream()
                    
                    SocketStream.ReadTimeout = -1
                  
 
                    If SocketStream.CanRead Then
                    
                    
                    	If SocketStream.DataAvailable = True Then

                            Dim RecvData As Byte() = New Byte((mySocket.ReceiveBufferSize + 1) - 1) {}
                            
                            Dim RecvBytes As Integer = SocketStream.Read(RecvData, 0, RecvData.Length)

                            Dim TranLen As Short = System.Net.IPAddress.NetworkToHostOrder(BitConverter.ToInt16(RecvData, 0))

                            ResponseStr = System.Text.Encoding.ASCII.GetString(RecvData, 2, RecvBytes - 2)
                            '
                            ' determine if more to read
                            '
                            TranLen = CShort(TranLen - RecvBytes)
                            
                            If TranLen > 0 Then
                            
                            	Try
                            
                            		RecvBytes = SocketStream.Read(RecvData, 0, RecvData.Length)
                            
                            	Catch ex As Exception
                            
                            		RecordInfo("Multiple Read Failed ", EventLogEntryType.Warning, 10003)
                            
                            	End Try
                            
                            	If RecvBytes <> 0 Then
                            
                            		ResponseStr = String.Concat(ResponseStr, System.Text.Encoding.ASCII.GetString(RecvData, 0, RecvBytes))
                            
                            	End If
                            
                            End If
                           
                           RecordInfo("In: " & ResponseStr, EventLogEntryType.Warning, 10003)
                           
                           write_file("In: " & ResponseStr)

                            sendtogatewaynet(ResponseStr, RecvBytes)

                            ResponseStr = recvfromgatewaynet()

                            RecordInfo("Out: " & ResponseStr, EventLogEntryType.Warning, 10003)

                            If ResponseStr.Length > 0 Then

                                If sendtorelay(ResponseStr) = False Then
                                
                                 	RecordInfo("send to relay failed ", EventLogEntryType.Warning, 10003)
                               
                               End If
                            
                            End If
                        
                        Else
                        
                         	ResponseStr = recvfromgatewaynet()
                        
                        	If ResponseStr <> "" Then
                        
                        	RecordInfo("Out: " & ResponseStr, EventLogEntryType.Warning, 10003)
                        
                        		If ResponseStr.Length > 0 Then

                        	            If sendtorelay(ResponseStr) = False Then
                        
                        			RecordInfo("send to relay failed ", EventLogEntryType.Warning, 10003)
                        
                        		    End If
                        
                        		End If
                        
                        	End If
                        
                        End If
                    
                    End If

                End If
            Catch ex As Exception
                MessageBox.Show("Error " & ex.Message)
                Exit While
            End Try

        End While

    End Sub
    
'
' subroutine to connect to namedpipes
'
        Friend Sub connecttopipenet()
    
    
            out_pipeName = lblPipename.Text & "RP"
            in_pipeName = lblPipename.Text & "SP"
    
            If blnRecvPipeConnected = False Or blnSendPipeConnected = False Then
            
                RecordInfo(String.Concat("Registering NamedPipe: ", lblPipename.Text), EventLogEntryType.Information, 10003)
    
                Try
                
                    namedpipe_out = New NamedPipeClientStream(".", out_pipeName, PipeDirection.Out, PipeOptions.None)
    
                    namedpipe_out.Connect()
    
                    namedpipe_in = New NamedPipeClientStream(".", in_pipeName, PipeDirection.In, PipeOptions.None)
    
                    namedpipe_in.Connect()
    
                    blnRecvPipeConnected = True
                    blnSendPipeConnected = True
    
    
                    RecordInfo(String.Concat("NamedPipe: ", lblPipename.Text, " Connected ", hpipeS, ":", hpipeR), EventLogEntryType.Information, 10003)
                    ScreenInfo()
    
                Catch ex As Exception
                    MessageBox.Show(ex.Message)
                    RecordInfo(String.Concat("NamedPipe Error: ", lblPipename.Text, " - ", ex.Message), EventLogEntryType.Information, 10003)
                End Try
            End If
    End Sub
    
'
' subroutine to send transaction to named pipes
'
    Private Sub sendtogatewaynet(ByRef transaction As String, ByRef translength As Integer)
        Try
            Dim pipe_write_process As New StreamWriter(namedpipe_out)

            pipe_write_process.AutoFlush = True

            pipe_write_process.WriteLine(transaction)

            RecordInfo(String.Concat("Error after writefile: ", Err.LastDllError & ": " & APIErrorDescription(Err.LastDllError)), EventLogEntryType.Error, 10013)

        Catch ex As Exception
            RecordInfo(String.Concat("Send failed from namedPipe: ", out_pipeName, " - ", ex.Message), EventLogEntryType.Information, 10003)

        End Try

    End Sub   
   
'
' function to return data from named pipes
'
   Private Function recvfromgatewaynet() As String

        Dim rtn As Integer
        Dim returnvalue As Long = 0

        Try
            Dim enc As New System.Text.ASCIIEncoding()

            Dim pipe_read_process = New StreamReader(namedpipe_in)

            rtn = 0

            rtn = pipe_read_process.Peek()            <-------- hangs here if NO data on pipe to read.

            If pipe_read_process.Read(mygatewayrecvbuffer, 0, BUFFSIZE) = Nothing Then
            
                recvfromgatewaynet = 0
                
            End If

            recvfromgatewaynet = CStr(mygatewayrecvbuffer)

        Catch ex As Exception
            RecordInfo(String.Concat("Read failed from namedPipe: ", in_pipeName, " - ", ex.Message), EventLogEntryType.Information, 10003)
            recvfromgatewaynet = False
        End Try


    End Function

[dglienna]

Try a catch block AFTER this line, and then another for the next parts. It should exit right here:

  namedpipe_in.Connect()

Also, go back and add CODE TAGS to your code (see above). Too hard to read unstructured code.

[rknelsen]

Ok I changed the connect piece to be in a try catch block but the namedpipe_in.connect() does not fail.

  Public Sub connecttopipenet()


        out_pipeName = lblPipename.Text & "RP"
        in_pipeName = lblPipename.Text & "SP"

        If blnRecvPipeConnected = False Or blnSendPipeConnected = False Then
            RecordInfo(String.Concat("Registering NamedPipe: ", lblPipename.Text), EventLogEntryType.Information, 10003)

            Try
                namedpipe_out = New NamedPipeClientStream(".", out_pipeName, PipeDirection.Out, PipeOptions.None)

                namedpipe_out.Connect()

            Catch ex As Exception
                MessageBox.Show(ex.Message)
                RecordInfo(String.Concat("NamedPipe Error: ", lblPipename.Text, " - ", ex.Message), EventLogEntryType.Information, 10003)
            End Try

            Try
                namedpipe_in = New NamedPipeClientStream(".", in_pipeName, PipeDirection.In, PipeOptions.None)

                namedpipe_in.Connect()

            Catch ex As Exception
                MessageBox.Show(ex.Message)
                RecordInfo(String.Concat("NamedPipe Error: ", lblPipename.Text, " - ", ex.Message), EventLogEntryType.Information, 10003)
            End Try


            Try
                blnRecvPipeConnected = True
                blnSendPipeConnected = True

                RecordInfo(String.Concat("NamedPipe: ", lblPipename.Text, " Connected ", hpipeS, ":", hpipeR), EventLogEntryType.Information, 10003)
                ScreenInfo()

            Catch ex As Exception
                MessageBox.Show(ex.Message)
                RecordInfo(String.Concat("NamedPipe Error: ", lblPipename.Text, " - ", ex.Message), EventLogEntryType.Information, 10003)
            End Try
        End If
    End Sub

[dglienna]

See if this helps:

http://support.microsoft.com/?kbid=871044

[rknelsen]

CalledNamePipe appears to write and read to the same pipe.

In my application I need to write to 1 pipe and read from another pipe as this is the way the legacy program works.

so would need to write to something like \\.\pipe\pipeSP and read from pipe \\.\pipe\pipeRP.

[dglienna]

Async http://www.codeproject.com/KB/vb/AsyncNamedPipes.aspx

[rknelsen]

Thanks.

Changing to Async, by specifing FILE_FLAG_OVERLAPPED in hpipeS = CreateFile(out_pipeName, GENERIC_WRITE, 0, sa, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, FILE_FLAG_OVERLAPPED), resolved this issue.