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# DISPATCH_BLOCK_NO_QOS_CLASS

Execute the work item without assigning a quality-of-service class.

```
DISPATCH_BLOCK_NO_QOS_CLASS
```

## Discussion

Indicates that a dispatch block should be not be assigned a QoS class. If invoked directly, the block object will be executed with the QoS class of the calling thread. If the block object is submitted to a queue, this replaces the default behavior of associating the submitted block instance with the QoS class current at the time of submission. This flag is ignored if a specific QoS class is assigned with the [`dispatch_block_create_with_qos_class`](/documentation/Dispatch/dispatch_block_create_with_qos_class) function.

---

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