Hi,

As I understand, if a code section inside a sub called with threadX.Start
is between BeginCriticalRegion - EndCriticalRegion, it should complete (at
least that portion of code, not the whole 'sub'... even if a TreadX.Abort is
used, if this portion of code is running when you call that Abort.

So With this program, I would expect to print :

I'm still standing, yeh yeh yéah
Main thread finished

But only

Main thread finished

appears because thread is aborted although The code between critical region
is running... Why ?

Code:


Sub Main()


Dim myThreadx As New Thread(AddressOf subWithASleep)
myThreadx.Start()
Thread.Sleep(2000) 'For the called thread to have some time to enter that
"begin-critical-region"

myThreadx.Abort()
Console.WriteLine("Main thread finished")

end sub


Public Sub subWithASleep()

Thread.BeginCriticalRegion()

Thread.Sleep(15000) 'waits 15 seconds
Console.Write("I'm still standing, yeh yeh yéah") 'It should show
but it does NOT !

Thread.EndCriticalRegion()

End Sub


--
Roger
..NET 2005 and DB developer

Are you confusing Critical Regions and Constrained Execution Regions?

BeginCriticalRegion/EndCriticalRegion is used to signify a critical region
of code--a region of code that non-atomically modifies data shared with other
threads. Interruption of code in critical region of code generally would
affect other threads. BeginCriticalRegion/EndCriticalRegion don't stop code
from being interrupted; it allows the host to decide what to do if a critical
region does get interrupted (like unload the AppDomain the code is in).

Manually specifying critical regions when using Monitor (and hence the
lock/SyncLock keywords) or Mutex appears largely redundant as Monitor and
Mutex already do this (as described by Jeffery Richter [1]; although I can
find no Microsoft documentation on this).

Are you trying to write a block of code that can't be interrupted?

[1]
http://msdn.microsoft.com/msdnmag/is...s/default.aspx


--
Browse http://connect.microsoft.com/VisualStudio/feedback/ and vote.
http://www.peterRitchie.com/blog/
Microsoft MVP, Visual Developer - Visual C#


"Roger" wrote:

> Hi,
>
> As I understand, if a code section inside a sub called with threadX.Start
> is between BeginCriticalRegion - EndCriticalRegion, it should complete (at
> least that portion of code, not the whole 'sub'... even if a TreadX.Abort is
> used, if this portion of code is running when you call that Abort.
>
> So With this program, I would expect to print :
>
> I'm still standing, yeh yeh yéah
> Main thread finished
>
> But only
>
> Main thread finished
>
> appears because thread is aborted although The code between critical region
> is running... Why ?
>
> Code:
>
>
> Sub Main()
>
>
> Dim myThreadx As New Thread(AddressOf subWithASleep)
> myThreadx.Start()
> Thread.Sleep(2000) 'For the called thread to have some time to enter that
> "begin-critical-region"
>
> myThreadx.Abort()
> Console.WriteLine("Main thread finished")
>
> end sub
>
>
> Public Sub subWithASleep()
>
> Thread.BeginCriticalRegion()
>
> Thread.Sleep(15000) 'waits 15 seconds
> Console.Write("I'm still standing, yeh yeh yéah") 'It should show
> but it does NOT !
>
> Thread.EndCriticalRegion()
>
> End Sub

Thanks, Peter. I'll take a deeper look at this.

Bye,

--
Roger Tranchez
..NET 2005 and DB developer


"Peter Ritchie [C# MVP]" wrote:

> Are you confusing Critical Regions and Constrained Execution Regions?
>
> BeginCriticalRegion/EndCriticalRegion is used to signify a critical region
> of code--a region of code that non-atomically modifies data shared with other
> threads. Interruption of code in critical region of code generally would
> affect other threads. BeginCriticalRegion/EndCriticalRegion don't stop code
> from being interrupted; it allows the host to decide what to do if a critical
> region does get interrupted (like unload the AppDomain the code is in).
>
> Manually specifying critical regions when using Monitor (and hence the
> lock/SyncLock keywords) or Mutex appears largely redundant as Monitor and
> Mutex already do this (as described by Jeffery Richter [1]; although I can
> find no Microsoft documentation on this).
>
> Are you trying to write a block of code that can't be interrupted?
>
> [1]
> http://msdn.microsoft.com/msdnmag/is...s/default.aspx
>
>
> --
> Browse http://connect.microsoft.com/VisualStudio/feedback/ and vote.
> http://www.peterRitchie.com/blog/
> Microsoft MVP, Visual Developer - Visual C#
>
>
> "Roger" wrote:
>
> > Hi,
> >
> > As I understand, if a code section inside a sub called with threadX.Start
> > is between BeginCriticalRegion - EndCriticalRegion, it should complete (at
> > least that portion of code, not the whole 'sub'... even if a TreadX.Abort is
> > used, if this portion of code is running when you call that Abort.
> >
> > So With this program, I would expect to print :
> >
> > I'm still standing, yeh yeh yéah
> > Main thread finished
> >
> > But only
> >
> > Main thread finished
> >
> > appears because thread is aborted although The code between critical region
> > is running... Why ?
> >
> > Code:
> >
> >
> > Sub Main()
> >
> >
> > Dim myThreadx As New Thread(AddressOf subWithASleep)
> > myThreadx.Start()
> > Thread.Sleep(2000) 'For the called thread to have some time to enter that
> > "begin-critical-region"
> >
> > myThreadx.Abort()
> > Console.WriteLine("Main thread finished")
> >
> > end sub
> >
> >
> > Public Sub subWithASleep()
> >
> > Thread.BeginCriticalRegion()
> >
> > Thread.Sleep(15000) 'waits 15 seconds
> > Console.Write("I'm still standing, yeh yeh yéah") 'It should show
> > but it does NOT !
> >
> > Thread.EndCriticalRegion()
> >
> > End Sub
>