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From: andrewb on 3 Jul 2008 06:39
Hi all,

Having some trouble using named pipes and Visual Basic .NET and would
appreciate and help you could offer.

Essentially I am trying to develop a simple client/server application
that exchanges text messages using named pipes. The internet resources
seem a bit scarce and the only Microsoft resource I can find is
http://support.microsoft.com/kb/871044.

I have managed to get the above KB example working but I am struggling
to convert it to just use string data between the client & server.

Anyone done this already using Visual Basic .NET?

Cheers.

From: kimiraikkonen on 3 Jul 2008 10:04
On Jul 3, 1:39 pm, andrewb <ajba...(a)deloitte.co.uk> wrote:
> Hi all,
>
> Having some trouble using named pipes and Visual Basic .NET and would
> appreciate and help you could offer.
>
> Essentially I am trying to develop a simple client/server application
> that exchanges text messages using named pipes. The internet resources
> seem a bit scarce and the only Microsoft resource I can find ishttp://support.microsoft.com/kb/871044.
>
> I have managed to get the above KB example working but I am struggling
> to convert it to just use string data between the client & server.
>
> Anyone done this already using Visual Basic .NET?
>
> Cheers.

Hi,
I hope that provides better info for sending strings using pipes:
http://msdn.microsoft.com/en-us/library/system.io.pipes.anonymouspipeserverstream.aspx

or:

http://msdn.microsoft.com/en-us/library/system.io.pipes.aspx

However you can also consider using System.Net.Sockets.

HTH,

Onur Güzel
From: Tom Shelton on 3 Jul 2008 11:59
On 2008-07-03, andrewb <ajbaker(a)deloitte.co.uk> wrote:
> Hi all,
>
> Having some trouble using named pipes and Visual Basic .NET and would
> appreciate and help you could offer.
>
> Essentially I am trying to develop a simple client/server application
> that exchanges text messages using named pipes. The internet resources
> seem a bit scarce and the only Microsoft resource I can find is
> http://support.microsoft.com/kb/871044.
>
> I have managed to get the above KB example working but I am struggling
> to convert it to just use string data between the client & server.
>
> Anyone done this already using Visual Basic .NET?
>
> Cheers.
>

What version of VB are you using? If your using 2008, then you might want to
take a look at System.IO.Pipes - they are now part of the framework. You can
find documentation and examples here:

http://msdn.microsoft.com/en-us/library/system.io.pipes.aspx

If you must use the API example... Then the simple answer is to convert your
strings to byte arrays before sending them accross the pipe:

' send data
Dim dataBuffer() As Byte = Encoding.Default.GetBytes(stringData)
WriteFile(......)


' receive data
ReadFile(...dataBuffer...)
....
Dim stringData As String = Encoding.Default.GetString(dataBuffer)

--
Tom Shelton
From: Tom Shelton on 3 Jul 2008 12:00
On 2008-07-03, Tom Shelton <tom_shelton(a)comcastXXXXXXX.net> wrote:
> On 2008-07-03, andrewb <ajbaker(a)deloitte.co.uk> wrote:
>> Hi all,
>>
>> Having some trouble using named pipes and Visual Basic .NET and would
>> appreciate and help you could offer.
>>
>> Essentially I am trying to develop a simple client/server application
>> that exchanges text messages using named pipes. The internet resources
>> seem a bit scarce and the only Microsoft resource I can find is
>> http://support.microsoft.com/kb/871044.
>>
>> I have managed to get the above KB example working but I am struggling
>> to convert it to just use string data between the client & server.
>>
>> Anyone done this already using Visual Basic .NET?
>>
>> Cheers.
>>
>
> What version of VB are you using? If your using 2008, then you might want to
> take a look at System.IO.Pipes - they are now part of the framework. You can
> find documentation and examples here:
>
> http://msdn.microsoft.com/en-us/library/system.io.pipes.aspx
>
> If you must use the API example... Then the simple answer is to convert your
> strings to byte arrays before sending them accross the pipe:
>
> ' send data
> Dim dataBuffer() As Byte = Encoding.Default.GetBytes(stringData)
> WriteFile(......)
>
>
> ' receive data
> ReadFile(...dataBuffer...)
> ...
> Dim stringData As String = Encoding.Default.GetString(dataBuffer)
>

I should probably mention... If all of your strings can be represented in
ASCII then, you can actually use Encoding.ASCII on both ends.

--
Tom Shelton
From: andrewb on 3 Jul 2008 12:47
Thanks for the help guys - appreciate it

I am using Visual Studio 2005, still unable to get a string through -
here is my code, hopefully you can spot my error(s) :

Server code
=========

Dim pipeName As String = "\\.\pipe\MServerPipe"
Dim hPipe As Integer
Dim openMode, pipeMode As Integer

Dim stringIn As String
Dim dataIn(256) As Byte

Dim res, nChars As Integer

openMode = PIPE_ACCESS_DUPLEX Or FILE_FLAG_WRITE_THROUGH
pipeMode = PIPE_WAIT Or PIPE_TYPE_MESSAGE Or
PIPE_READMODE_MESSAGE

hPipe = CreateNamedPipe(pipeName, openMode, pipeMode, 10,
10000, 2000, 10000, IntPtr.Zero)

res = ConnectNamedPipe(hPipe, 0)

res = ReadFile(hPipe, dataIn, 256, nChars, 0)
stringIn = System.Text.Encoding.ASCII.GetString(dataIn)

CloseHandle(hPipe)

Client code
========

Dim pipeName As String = "\\.\pipe\MServerPipe"

Dim res, cbRead, numBytes As Integer
Dim stringOut As String
Dim dataOut(256), dataIn(256) As Byte

stringOut = "This is a test"
dataOut = System.Text.Encoding.ASCII.GetBytes(stringOut)

res = CallNamedPipe(pipeName, dataOut, stringOut.Length,
dataIn, numBytes, cbRead, 30000)

API declarations
============

Public Declare Function CallNamedPipe Lib "kernel32" Alias
"CallNamedPipeA" _
(ByVal lpNamedPipeName As String, _
ByRef lpInBuffer() As Byte, _
ByVal nInBufferSize As Integer, _
ByRef lpOutBuffer() As Byte, _
ByVal nOutBufferSize As Integer, _
ByRef lpBytesRead As Integer, ByVal nTimeOut As Integer) As
Integer

Declare Function WriteFile Lib "kernel32" _
(ByVal hFile As Integer, ByRef lpBuffer() As Byte, _
ByVal nNumberOfBytesToWrite As Integer, ByRef
lpNumberOfBytesWritten As Integer, _
ByVal lpOverlapped As Integer _
) As Integer

Declare Function ReadFile Lib "kernel32" _
(ByVal hFile As Integer, ByVal lpBuffer() As Byte, _
ByVal nNumberOfBytesToRead As Integer, ByRef
lpNumberOfBytesRead As Integer, _
ByVal lpOverlapped As Integer _
) As Integer
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