Synchronization bool shared fields

[Vladimir]

Is synchronization for bool shared fields required in multithreaded
application?

Is there a cases when for example changing value from true to false in one
thread, when another thread is reading this field, will lead to true value
in this field?

[Jon Skeet [C# MVP]]

Re: Synchronization bool shared fields

Vladimir <xozar@tut.by > wrote:[color=blue]
> Is synchronization for bool shared fields required in multithreaded
> application?[/color]

Yes. It should either be volatile, or you should lock access.
[color=blue]
> Is there a cases when for example changing value from true to false in one
> thread, when another thread is reading this field, will lead to true value
> in this field?[/color]

It won't stop the first thread from actually writing the change out,
but you may not see the change when reading in the second thread unless
you have a lock or make the flag volatile.

--
Jon Skeet - <skeet@pobox.co m>

http://www.pobox.com/~skeet

If replying to the group, please do not mail me too

[Vladimir]

Re: Synchronization bool shared fields

>> Is synchronization for bool shared fields required in multithreaded[color=blue][color=green]
>> application?[/color]
>
> Yes. It should either be volatile, or you should lock access.
>[color=green]
>> Is there a cases when for example changing value from true to false in
>> one
>> thread, when another thread is reading this field, will lead to true
>> value
>> in this field?[/color]
>
> It won't stop the first thread from actually writing the change out,
> but you may not see the change when reading in the second thread unless
> you have a lock or make the flag volatile.[/color]

Thanks...

But wait a minute...
I'm using some classes from two threads (time to time, but always not in one
moment -
when some volatile bool variable is true, i'm using them from first thread,
when false
- from second). What about shared data in this objects? Can the new state be
invisible
from another thread?

[Jon Skeet [C# MVP]]

Re: Synchronization bool shared fields

Vladimir <xozar@tut.by > wrote:[color=blue]
> Thanks...
>
> But wait a minute... I'm using some classes from two threads (time to
> time, but always not in one moment - when some volatile bool variable
> is true, i'm using them from first thread, when false - from second).
> What about shared data in this objects? Can the new state be
> invisible from another thread?[/color]

Yes, if you don't have any locking in place.
See http://www.pobox.com/~skeet/csharp/t...latility.shtml

--
Jon Skeet - <skeet@pobox.co m>

http://www.pobox.com/~skeet

If replying to the group, please do not mail me too