Currently I have a setup which duplicates the stderr STDERR_FILENO pipe into a separate one. Then by setting up a readabilityHandler (on the new Pipe) I can capture the logged data and either store it inside a File, adjust/modify the data etc. Since iOS 17 this is not possible anymore (previous versions worked iOS 16)? I cannot find any documentation on why or what changed on the os_log side. private func setupPipes() { inputPipe.fileHandleForReading.readabilityHandler = { [weak self] handler in guard let strongSelf = self else { return } let data = handler.availableData strongSelf.queue.async(flags: .barrier) { guard let fileHandle = try? FileHandle(forWritingTo: strongSelf.filePath) else { return } fileHandle.seekToEndOfFile() fileHandle.write(data) try? fileHandle.close() } strongSelf.outputPipe.fileHandleForWriting.write(data) } dup2(STDERR_FILENO, outputPipe.fileHandleForWriting.fileDescriptor) dup2(inputPipe.fileHandleForWriting.fileDescriptor, STDERR_FILENO) }