---
title: CGDirectDisplayID
framework: coregraphics
role: symbol
role_heading: Type Alias
path: coregraphics/cgdirectdisplayid
---

# CGDirectDisplayID

A unique identifier for an attached display.

## Declaration

```swift
typealias CGDirectDisplayID = UInt32
```

## Discussion

Discussion In Quartz, the term display refers to a graphics hardware system consisting of a framebuffer, a color correction (gamma) table, and possibly an attached monitor. If no monitor is attached, a display is characterized as offline. When a monitor is attached, Quartz assigns a unique display identifier (ID). A display ID can persist across processes and typically remains constant until the machine is restarted. When assigning a display ID, Quartz considers the following parameters: Vendor Model Serial number Position in the I/O Kit registry For information about how to obtain a display ID, see Finding Displays.

## See Also

### Data Types

- [CGButtonCount](coregraphics/cgbuttoncount.md)
- [CGCharCode](coregraphics/cgcharcode.md)
- [CGDisplayBlendFraction](coregraphics/cgdisplayblendfraction.md)
- [CGDisplayConfigRef](coregraphics/cgdisplayconfigref.md)
- [CGDisplayCount](coregraphics/cgdisplaycount.md)
- [CGDisplayErr](coregraphics/cgdisplayerr.md)
- [CGDisplayFadeInterval](coregraphics/cgdisplayfadeinterval.md)
- [CGDisplayFadeReservationToken](coregraphics/cgdisplayfadereservationtoken.md)
- [CGDisplayMode](coregraphics/cgdisplaymode.md)
- [CGDisplayReconfigurationCallBack](coregraphics/cgdisplayreconfigurationcallback.md)
- [CGDisplayReservationInterval](coregraphics/cgdisplayreservationinterval.md)
- [CGDisplayStream](coregraphics/cgdisplaystream.md)
- [CGDisplayStreamFrameAvailableHandler](coregraphics/cgdisplaystreamframeavailablehandler.md)
- [CGDisplayStreamUpdate](coregraphics/cgdisplaystreamupdate.md)
- [CGEvent](coregraphics/cgevent.md)