Cant Stop A Thread

4 Aug 2006 2:15 AM

Miro

VB 2003. I cant find the last thing im missing.
I click the "Run" button to run my app in VB.net and it runs.
But when i close the application, the thread does not end ( i think )
because it never ends the debuger
and i have to hit the "little square" to stop the app.

If make a shortcut to the exe and run it that way, it stays in the Windows
Task Manager and I have to kill the process.

Has anyone else run into this / work around?

My thread opens a udp port and listens for data on a port. ( but i dont
think that matters )
For the example I used to create this, it is:
http://www.codeproject.com/vb/net/UDP_Send_Receive.asp

On FormLoad i open a new thread:
            ThreadReceive = _
                New System.Threading.Thread(AddressOf A_Sub )
            ThreadReceive.Start()

===
then in the
Public Sub A_Sub
    'I do stuff
EndSub

===
Then on form Close I call
MessageBox.Show( "yes i am closing the application" )
ThreadReceive.Suspend() 'Both of these or just 1 of these alone does not
work
ThreadReceive.Abort()
messagebox.show( "the thread should have stopped but it didnt and the app is
still in Windows Task Manager and never leaves the debuger." )

Thanks,

Miro

4 Aug 2006 3:22 AM

Tom Shelton

Miro wrote:
Show quoteHide quote

> VB 2003. I cant find the last thing im missing.
> I click the "Run" button to run my app in VB.net and it runs.
> But when i close the application, the thread does not end ( i think )
> because it never ends the debuger
> and i have to hit the "little square" to stop the app.
>
> If make a shortcut to the exe and run it that way, it stays in the Windows
> Task Manager and I have to kill the process.
>
> Has anyone else run into this / work around?
>
> My thread opens a udp port and listens for data on a port. ( but i dont
> think that matters )
> For the example I used to create this, it is:
> http://www.codeproject.com/vb/net/UDP_Send_Receive.asp
>

Actually, if your using blocking socket calls (ReceiveFrom?) then it
does matter. A call to Thread.Abort is only a request, it doesn't
guarentee that a thread will immediately exit. The problem with the
blocking socket calls is at the low level, they are actually calling
out into unmanaged code - and so the ThreadAbortException is not thrown
until the call returns (look at the docs for a more detailed
explanation). The way I usually handle this is simply close the
socket. This causes the blocking read to return, and then you can exit
the thread...

--
Tom Shelton [MVP]

4 Aug 2006 4:47 AM

Miro

Yes that worked.

Thank you Tom.

I though the socket and the UDP thread were one in the same and once set up
were interlinked.

Socket.close()
Thread.abort() ' works perfectly now

Thanks again.

Miro

Show quoteHide quote

"Tom Shelton" <t**@mtogden.com> wrote in message
news:1154661753.904533.263290@s13g2000cwa.googlegroups.com...
>
> Miro wrote:
>> VB 2003. I cant find the last thing im missing.
>> I click the "Run" button to run my app in VB.net and it runs.
>> But when i close the application, the thread does not end ( i think )
>> because it never ends the debuger
>> and i have to hit the "little square" to stop the app.
>>
>> If make a shortcut to the exe and run it that way, it stays in the
>> Windows
>> Task Manager and I have to kill the process.
>>
>> Has anyone else run into this / work around?
>>
>> My thread opens a udp port and listens for data on a port. ( but i dont
>> think that matters )
>> For the example I used to create this, it is:
>> http://www.codeproject.com/vb/net/UDP_Send_Receive.asp
>>
>
> Actually, if your using blocking socket calls (ReceiveFrom?) then it
> does matter. A call to Thread.Abort is only a request, it doesn't
> guarentee that a thread will immediately exit. The problem with the
> blocking socket calls is at the low level, they are actually calling
> out into unmanaged code - and so the ThreadAbortException is not thrown
> until the call returns (look at the docs for a more detailed
> explanation). The way I usually handle this is simply close the
> socket. This causes the blocking read to return, and then you can exit
> the thread...
>
> --
> Tom Shelton [MVP]
>