... and more importantly I do not believe your code makes correct use of dispatch_group_async. Your first call adds a producer block to the global concurrent queue, which may start executing immediately. At some time soon afterwards you add a consumer block to the global concurrent queue, which again may start executing immediately - while the producer block is still in the process of "producing". As far as I can see the code appears to have a number of major issues:
1. Theoretically your producer block may not have produced anything by the time your consumer block executes 2. What happens if your consumer block has processed all the currently-added blocks before the producer block has added the eof marker? 3. You have only one single consumer block, which means you will only have a single consumer "thread" running under Grand Central Dispatch, which rather defeats the purpose of using it at all! I think you may not have fully understood how GCD is intended to be used... 4. Are you sure that your mysterious and rather complicated-seeming CFDataConstBuffers class is sufficiently threadsafe for your producer to be adding to it at the same time as your consumer block is iterating through it? I am 99% sure that the "explicit" consumer code you wrote in ConcurrentProduceConsume is not threadsafe. Jonny._______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
