---
title: "CGGetDisplaysWithOpenGLDisplayMask(_:_:_:_:)"
framework: coregraphics
role: symbol
role_heading: Function
path: "coregraphics/cggetdisplayswithopengldisplaymask(_:_:_:_:)"
---

# CGGetDisplaysWithOpenGLDisplayMask(_:_:_:_:)

Provides a list of displays that corresponds to the bits set in an OpenGL display mask.

## Declaration

```swift
func CGGetDisplaysWithOpenGLDisplayMask(_ mask: CGOpenGLDisplayMask, _ maxDisplays: UInt32, _ displays: UnsafeMutablePointer<CGDirectDisplayID>?, _ matchingDisplayCount: UnsafeMutablePointer<UInt32>?) -> CGError
```

## Parameters

- `mask`: An OpenGL display mask that identifies one or more displays.
- `maxDisplays`: The size of the displays array. This value determines the maximum number of displays the list includes.
- `displays`: A pointer to storage you provide for an array of display IDs. On return, the array contains a list of displays that corresponds to the bits set in the mask. If you pass NULL, on return the display count contains the total number of displays specified in the mask.
- `matchingDisplayCount`: A pointer to a display count variable you provide. On return, the display count contains the actual number of displays the function added to the displays array. This value is at most maxDisplays.

## Return Value

Return Value A result code. To interpret the result code, see CGError.

## See Also

### Functions

- [CGAcquireDisplayFadeReservation(_:_:)](coregraphics/cgacquiredisplayfadereservation(_:_:).md)
- [CGAssociateMouseAndMouseCursorPosition(_:)](coregraphics/cgassociatemouseandmousecursorposition(_:).md)
- [CGBeginDisplayConfiguration(_:)](coregraphics/cgbegindisplayconfiguration(_:).md)
- [CGCancelDisplayConfiguration(_:)](coregraphics/cgcanceldisplayconfiguration(_:).md)
- [CGCaptureAllDisplays()](coregraphics/cgcapturealldisplays().md)
- [CGCaptureAllDisplaysWithOptions(_:)](coregraphics/cgcapturealldisplayswithoptions(_:).md)
- [CGCompleteDisplayConfiguration(_:_:)](coregraphics/cgcompletedisplayconfiguration(_:_:).md)
- [CGConfigureDisplayFadeEffect(_:_:_:_:_:_:)](coregraphics/cgconfiguredisplayfadeeffect(_:_:_:_:_:_:).md)
- [CGConfigureDisplayMirrorOfDisplay(_:_:_:)](coregraphics/cgconfiguredisplaymirrorofdisplay(_:_:_:).md)
- [CGConfigureDisplayMode(_:_:_:)](coregraphics/cgconfiguredisplaymode(_:_:_:).md)
- [CGConfigureDisplayOrigin(_:_:_:_:)](coregraphics/cgconfiguredisplayorigin(_:_:_:_:).md)
- [CGConfigureDisplayStereoOperation(_:_:_:_:)](coregraphics/cgconfiguredisplaystereooperation(_:_:_:_:).md)
- [CGConfigureDisplayWithDisplayMode(_:_:_:_:)](coregraphics/cgconfiguredisplaywithdisplaymode(_:_:_:_:).md)
- [CGCursorIsDrawnInFramebuffer()](coregraphics/cgcursorisdrawninframebuffer().md)
- [CGCursorIsVisible()](coregraphics/cgcursorisvisible().md)