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Subject: Re: [boost] [Boost.utility]
From: Stewart, Robert (Robert.Stewart_at_[hidden])
Date: 2010-01-27 17:02:42


Andrew Chinkoff wrote:
>
> Ok, I see. I would try to explain.

[snip lots of code trying to explain "atomic"]

> ATOMIC(code) ensures that "code" will be executed
> consistently with all threads.
> "Mutex'ed code" is the part of code, that is protected with
> mutex locker.

I don't understand the difference between what you describe as ATOMIC(code) and putting "code" into a critical section controlled by a mutex.

> I assume that boost::call_once does so:
>
> if(ATOMIC(!flag1)) // (2)
> {
> Locker locker;
> ...
> }

Steven already noted that call_once ensures that one and only one thread runs the supplied functor; any contending threads block until the functor completes. That's pretty clear. If that's still not what you want to know, I'm at a loss to understand even yet.

_____
Rob Stewart robert.stewart_at_[hidden]
Software Engineer, Core Software using std::disclaimer;
Susquehanna International Group, LLP http://www.sig.com

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