# init(platformString:) Creates a file path root by copying bytes from a null-terminated platform string. It is a precondition that a null byte indicates the end of the string. The absence of a null byte will trigger a runtime error. ``` init?(platformString: [CInterop.PlatformChar]) ``` ## Parameters `platformString` A null-terminated platform string. ## Discussion Returns `nil` if `platformString` is empty or is not a root. - Note It is a precondition that `platformString` must be null-terminated. The absence of a null byte will trigger a runtime error. --- 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)