Stackoverflowexception :- tcpclient

Question

0.00/5 (No votes)

See more:

Dear All,

Here I have a client whose code is as below. This code is connects to server and runs perfectly when server is up. Issue is if server is down then it gives

System.StackOverFlowException

after 100 loops. However, if server is up and gets disconnects in between RemoteConnect loop works till max counter.

VB

'Globally Defined 
 Dim lTCPClientRemote As New TcpClient
 Dim lServerIp As String
 Dim lServerPort As String
 Dim lNetworkStreamRemote As System.Net.Sockets.NetworkStream
 Dim lRemoteWriteStream As System.IO.StreamWriter
 Dim lRemoteReadStream As System.IO.StreamReader
 Dim lRemoteReceiverThread As Threading.Thread = Nothing
 Dim lconnecttries As Integer = 0


 Private Sub frm_Load(sender As Object, e As EventArgs) Handles MyBase.Load
    
    Dim lRemoteThread As New System.Threading.Thread(AddressOf RemoteConnect)
    lRemoteThread.IsBackground = True
    lRemoteThread.Start()
           
 End Sub

 Private Sub RemoteConnect()
        Try
            lTCPClientRemote = New TcpClient()
            lServerIp = "127.0.0.1"
            lServerPort = "1000"
            lTCPClientRemote.Connect(lServerIp, lServerPort)'System.StackOverFlowException is here after 100 loops

           If lTCPClientRemote.Connected() Then
             
                lconnecttries = 0
                lNetworkStreamRemote = lTCPClientRemote.GetStream()
                lRemoteReadStream = New System.IO.StreamReader(lNetworkStreamRemote)
                lRemoteWriteStream = New System.IO.StreamWriter(lNetworkStreamRemote)
                lRemoteReceiverThread = New Threading.Thread(AddressOf ProcessMsg)
                lRemoteReceiverThread.Start()
           Else
               'Function to display remote connection status
                UpdateStatusMess("Unable to Connect Remote Machine", "2")
           End If
       Catch Ex As SocketException
            'Function to display remote connection status
            UpdateStatusMess("Unable to Connect Remote Machine", "2")
            
            lconnecttries  = lconnecttries  + 1

            If lconnecttries  <= 1000 Then
                Threading.Thread.Sleep(5000) ' 5 second
                RemoteConnect()
            Else
                Exit Sub
            End If
        End Try
    End Sub

Kindly help and suggest if any changes need to done.

What I have tried:

I have tried to dispose

lTCPClientRemote.Dispose()

in exception, but it did not work.

Posted 27-Jul-21 2:42am

Magic Wonder

Updated 27-Jul-21 3:00am

Add a Solution

2 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Richard MacCutchan · Accepted Answer · 2021-07-27T02:57:00

Solution 1

You have a recursive call in your code:

VB

If lconnecttries  <= 1000 Then
    Threading.Thread.Sleep(5000) ' 5 second
    RemoteConnect()

Which will likely lead to a stack overflow error.

Posted 27-Jul-21 2:57am

Richard MacCutchan

Comments

Magic Wonder 27-Jul-21 9:01am

Yes, I have to call it recursively up to 1000 times. And same is working when it disconnects in between.

Richard MacCutchan 27-Jul-21 9:22am

No, you do not need to call it recursively; you should use a properly controlled loop.

Magic Wonder 30-Jul-21 0:45am

Thank you for your suggestion.

Magic Wonder 30-Jul-21 0:46am

Used controlled loop.

OriginalGriff · Accepted Answer · 2021-07-27T03:00:00

Solution 2

Quote:
System.StackOverFlowException is here after 100 loops

That isn't a loop: it's a recursive call.
So each time you call RemoteConnect it takes a bit more stack space - and it's not massive to start with - so at some point it will run out of stack and you get an overflow exception.

There is no good reason for that code to be recursive: a simple loop would be both more obvious and efficient.
And move local variables into the method they are used in - it's pointless having them at class level if they are only accessed or relevant in a single method!

Posted 27-Jul-21 3:00am

OriginalGriff

Comments

Magic Wonder 27-Jul-21 9:08am

1. Can we clear stack in exception?
2. variables kept class level as using them in other functions also on same connection for requests and responses.

OriginalGriff 27-Jul-21 9:34am

1 No. The stack is a small area of memory that is part of the thread, and is used for local variables and method return addresses. You have no direct access to it, and if you did you would screw your app up royally if you tried to modify it!
2) Some, yes - if they are class related. But "retry counts" aren't, and most of the others should be passed through as method parameters or return values rather than assigned as "class level globals". That way your code is more structured, more flexible, easier to maintain, and less "interlocked".

Magic Wonder 30-Jul-21 0:45am

Thank you for your valuable details.

Magic Wonder 27-Jul-21 10:00am

1) ok
2) I will check and try to make use of proper loop instead of recursive call.
3) Retry count, here declared for understanding purpose, however same is also in use globally.