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# CGDisplayIsAsleep(_:)

Returns a Boolean value indicating whether a display is sleeping (and is therefore not drawable).

```
func CGDisplayIsAsleep(_ display: CGDirectDisplayID) -> boolean_t
```

## Parameters

`display`

The identifier of the display to be accessed.

## Return Value

If <doc://com.apple.documentation/documentation/Swift/true>, the specified display is in sleep mode; otherwise, <doc://com.apple.documentation/documentation/Swift/false>.

## Discussion

A display is sleeping when its framebuffer and the attached monitor are in reduced power mode. A sleeping display is still considered to be a part of global display (desktop) space, but it is not drawable.

---

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