[objc] block, 큐, 병렬처리

** Global Queue

    dispatch_queue_t syncQueue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);

    dispatch_async(syncQueue, ^{

});

** Main Queue

dispatch_async(dispatch_get_main_queue(), ^{

        });

** private Queue

dispatch_queue_t queue;

queue = dispatch_queue_create("com.example.MyQueue", NULL);

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Simple block sample

int x = 123;
int y = 456;
 
// Block declaration and assignment
void (^aBlock)(int) = ^(int z) {
    printf("%d %d %d\n", x, y, z);
};
 
// Execute the block
aBlock(789);   // prints: 123 456 789

https://developer.apple.com/library/ios/documentation/General/Conceptual/ConcurrencyProgrammingGuide/OperationQueues/OperationQueues.html

************

...Block:(void(^)(int b, intc))block{

     block(1, 2);

}