Thanks.

Whole file ? As per the documentation, If the device has not yet downloaded the file at the given URL, this method blocks (potentially for a long time) while the file is downloaded. If the file cannot be downloaded, this method fails.. I need a method to pass a URL to AVAsset and ensure that only the specified offset range is read from the AVFoundation library

Yes. This is what I do after enumerate the received URL. let stop = fileURL.startAccessingSecurityScopedResource() defer { if stop { fileURL.stopAccessingSecurityScopedResource() } } let permissions: mode_t = 0o644 let err = chmod(fileURL.path, permissions) if err != 0 { print("chmod failed: \(String(cString: strerror(errno)))") }

First option, There is a warning sign :( Only use waitForStabilization(completionHandler:) for testing and debugging. Don’t call this method in a production app, due to its high performance cost.

Second option didn't work. chmod throws Operation not permitted error, both in code and in the terminal (even with sudo).