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# CMBufferQueueTestTrigger(_:triggerToken:)

Tests whether the trigger condition is true for the specified buffer queue.

```
func CMBufferQueueTestTrigger(_ queue: CMBufferQueue, triggerToken: CMBufferQueueTriggerToken) -> Bool
```

## Parameters

`queue`

`CMBufferQueue` on which the trigger is tested.

`triggerToken`

Trigger to test.

## Return Value

A Boolean indicating whether the trigger condition is True.

## Discussion

[CMBufferQueue](/documentation/CoreMedia/cmbufferqueue-api) always returns the condition’s current status. The trigger callback will only be called when the condition goes from false to true. The `triggerToken` must be one that has been installed on this queue.

---

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