CGGetOnlineDisplayList(_:_:_:)

Declaration

func CGGetOnlineDisplayList(_ maxDisplays: UInt32, _ onlineDisplays: UnsafeMutablePointer<CGDirectDisplayID>?, _ displayCount: UnsafeMutablePointer<UInt32>?) -> CGError

Parameters

• maxDisplays:

  The size of the onlineDisplays array. This value determines the maximum number of display IDs that can be returned.

• onlineDisplays:

  A pointer to storage provided by the caller for an array of display IDs. On return, the array contains a list of the online displays. If you pass NULL, on return the display count contains the total number of online displays.

• displayCount:

  A pointer to a display count variable provided by the caller. On return, the display count contains the actual number of displays returned in the onlineDisplays array. This value is at most maxDisplays.

Return Value

A result code. See Core Graphics Data Types and Constants.

Discussion

If the framebuffer hardware is connected, a display is considered connected or online.

When hardware mirroring is used, a display can be online but not active or drawable. Programs that manipulate display settings (such as gamma tables) need access to all displays, including hardware mirrors, which are not drawable.

See Also

Functions

• CGAcquireDisplayFadeReservation(_:_:)
• CGAssociateMouseAndMouseCursorPosition(_:)
• CGBeginDisplayConfiguration(_:)
• CGCancelDisplayConfiguration(_:)
• CGCaptureAllDisplays()
• CGCaptureAllDisplaysWithOptions(_:)
• CGCompleteDisplayConfiguration(_:_:)
• CGConfigureDisplayFadeEffect(_:_:_:_:_:_:)
• CGConfigureDisplayMirrorOfDisplay(_:_:_:)
• CGConfigureDisplayMode(_:_:_:)
• CGConfigureDisplayOrigin(_:_:_:_:)
• CGConfigureDisplayStereoOperation(_:_:_:_:)
• CGConfigureDisplayWithDisplayMode(_:_:_:_:)
• CGCursorIsDrawnInFramebuffer()
• CGCursorIsVisible()