Re: [boost] [interprocess] Atomic read and write.

From: Peter Dimov (pdimov_at_[hidden])
Date: 2007-10-11 04:51:34

Markus Schöpflin:

> Sorry for being dense, but what exactly do you mean when you say a read
> might not be atomic? Are you thinking of memory barriers here? Or is it
> something else? Is there somewhere a definition of what atomic exactly
> means here?

Atomic means that when you read the value, you get back either the initial 
value, or one of the values that have been written (by the abstract machine) 
so far, even in the presence of data races.

Atomicity by itself is rarely useful without acquire/release guarantees, so 
memory barriers are definitely part of the same story.