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    <p>If the parent's vector's contents is re-allocated after spawning your worker threads, then their pointers, references, iterators, or whatever are <em>almost certainly</em> invalid. A list MAY be different (given how they're allocated) but I don't know, and may even be platform-dependent.</p> <p>Basically, if you have multiple worker threads, it's probably safest to actually have a method on the parent class to dump the results back into as long as the copy isn't that taxing. Sure it's not as good as allocating directly into the parent, but then you need to ensure the container you're dumping into doesn't get "lost" on re-allocation.</p> <p>If the list you're using is guaranteed not to re-allocate its "other" space when members are added (or deleted), then that would achieve what you're looking for, but the vector is definitely unsafe. But either way, the way in which you access it (pointer, reference, or iterator) <em>probably</em> doesn't matter that much as long as your "root container" isn't going to move around its contents.</p> <p>Edit:</p> <p>As mentioned in the comments below, here's a block about the list from <a href="http://www.sgi.com/tech/stl/List.html" rel="nofollow noreferrer">SGI's website</a> (emphasis mine) :</p> <blockquote> <p><strong>Lists have the important property that insertion and splicing do not invalidate iterators to list elements, and that even removal invalidates only the iterators that point to the elements that are removed.</strong> The ordering of iterators may be changed (that is, list::iterator might have a different predecessor or successor after a list operation than it did before), but the iterators themselves will not be invalidated or made to point to different elements unless that invalidation or mutation is explicit.</p> </blockquote> <p>So this basically says "use a list as your master store" and then each worker can dump into its own, and knows it won't get invalidated when another worker is completely done and their vector is deleted from the list.</p>
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    1. POIterator vs. Reference vs. Pointer
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    1. COList iterators remain valid as long as the element they are currently pointing to hasn't been erased.
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    2. COYou are right, Autopulated. The author can refer to http://stackoverflow.com/questions/1436020/c-stl-containers-whats-the-difference-between-deque-and-list/1436038#1436038 in the paragraph about lists.
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    3. CO@fogo: thanks, I edited my OP to add the text from SGI's site.
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