# CGGetDisplaysWithRect(_:_:_:_:) Gets a list of online displays with bounds that intersect the specified rectangle. ``` func CGGetDisplaysWithRect(_ rect: CGRect, _ maxDisplays: UInt32, _ displays: UnsafeMutablePointer?, _ matchingDisplayCount: UnsafeMutablePointer?) -> CGError ``` ## Parameters `rect` The location and size of a rectangle in the global display coordinate space. The origin is the upper-left corner of the main display. `maxDisplays` The size of the `displays` array. This value determines the maximum number of displays that can be returned in the `displays` parameter. Generally, you should specify a number greater than 0 for this parameter. If you specify 0, the value returned in `matchingDisplayCount` is undefined and this function sets the `displays` parameter to `NULL`. `displays` A pointer to storage provided by the caller for an array of display IDs. On return, the array contains a list of displays whose bounds intersect the specified rectangle. `matchingDisplayCount` A pointer to a display count variable provided by the caller. On return, this variable contains the number of displays that were returned in the `displays` parameter. You must provide a non-`NULL` value for this parameter. ## Return Value A result code. See `Core Graphics Data Types and Constants`. ## Discussion If the `dspys` array is `NULL`, this function ignores the `maxDisplays` parameter. If the `maxDisplays` parameter is `0`, this function ignores the `displays` array. In any case, this function fills in the `matchingDisplayCount` pointer with the number of displays that intersect the specified rectangle. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)