dispatch_get_global_queue
Returns a system-defined global concurrent queue with the specified quality-of-service class.
Declaration
extern dispatch_queue_global_t dispatch_get_global_queue(intptr_t identifier, uintptr_t flags);Parameters
- identifier:
The quality of service you want to give to tasks executed using this queue. Quality-of-service helps determine the priority given to tasks executed by the queue. You may specify the values
QOS_CLASS_USER_INTERACTIVE,QOS_CLASS_USER_INITIATED,QOS_CLASS_UTILITY, orQOS_CLASS_BACKGROUND. Queues that handle user-interactive or user-initiated tasks have a higher priority than tasks meant to run in the background.In OS X 10.9 or earlier, you can specify one of the dispatch queue priority values, which are found in Dispatch_queue_priority_t. These values map to an appropriate quality-of-service class.
- flags:
Flags that are reserved for future use. Always specify
0for this parameter.
Return Value
The requested global concurrent queue.
Discussion
This function returns a queue suitable for executing tasks with the specified quality-of-service level. Calls to the suspend(), resume(), and dispatch_set_context functions have no effect on the returned queues.
Tasks submitted to the returned queue are scheduled concurrently with respect to one another.