dispatch_queue_create

label

const char *

A string indicating the queue name. label is an example for debug. You can rename it as you like. NULL is allowed.

attr

dispatch_queue_attr_t

Three types of parameters are allowed:

• DISPATCH_QUEUE_SERIAL, NULL, or 0: Creates a serial queue with the DEFAULT priority.
• DISPATCH_QUEUE_CONCURRENT: Creates a concurrent queue with the DEFAULT priority.
• Return of dispatch_queue_attr_make_with_qos_class: Defines a queue attribute for creating a queue with the specific priority.

dispatch_queue_t

The new queue.