# CFURLGetBytes(_:_:_:) Returns by reference the byte representation of a URL object. ``` func CFURLGetBytes(_ url: CFURL!, _ buffer: UnsafeMutablePointer!, _ bufferLength: CFIndex) -> CFIndex ``` ## Parameters `url` The URL object to convert to a byte representation. `buffer` The buffer where you want the bytes to be placed. If the buffer is of insufficient size, returns `-1` and no bytes are placed in buffer. If `NULL` the needed length is computed and returned. The returned bytes are the original bytes from which the URL was created (*not* including the base URL). If the URL was created from a string, the bytes are the bytes of the string encoded via UTF-8. `bufferLength` The number of bytes in `buffer`. ## Return Value Returns the number of bytes in `buffer` that were filled. If the buffer is of insufficient size, returns `-1`. ## Discussion --- 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)