# CFURLCreateWithFileSystemPathRelativeToBase(_:_:_:_:_:) Creates a `CFURL` object using a local file system path string relative to a base URL. ``` func CFURLCreateWithFileSystemPathRelativeToBase(_ allocator: CFAllocator!, _ filePath: CFString!, _ pathStyle: CFURLPathStyle, _ isDirectory: Bool, _ baseURL: CFURL!) -> CFURL! ``` ## Parameters `allocator` The allocator to use to allocate memory for the new `CFURL` object. Pass `NULL` or [`kCFAllocatorDefault`](/documentation/CoreFoundation/kCFAllocatorDefault) to use the current default allocator. `filePath` The path string to convert to a `CFURL` object. `pathStyle` The operating system path style used in the `filePath` string. See [`CFURLPathStyle`](/documentation/CoreFoundation/CFURLPathStyle) for a list of possible values. `isDirectory` A Boolean value that specifies whether `filePath` is treated as a directory path when resolving against relative path components. Pass `true` if the pathname indicates a directory, `false` otherwise. `baseURL` The base URL against which to resolve the `filePath`. ## Return Value A new `CFURL` object. Ownership follows the create rule. See [The Create Rule](https://developer.apple.com/library/archive/documentation/CoreFoundation/Conceptual/CFMemoryMgmt/Concepts/Ownership.html#//apple_ref/doc/uid/20001148-103029). ## Discussion This function takes a path name in the form of a `CFString` object, resolves it against a base URL, and returns a new `CFURL` object containing the result. --- 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)