In my app the user can select a source folder to be synced with a destination folder. The sync can also happen in response to a change in the source folder detected with FSEventStreamCreate. If the user unzips an archive in the source folder and the sync process begins before the unzip operation has completed, the sync can fail because of a "Permission denied" error. I assume this is related to the posix permissions of the extracted folder being 420 during the unzip operation and (in my case) 511 afterwards. Is there a way to detect than an unzip operation is in progress and wait until it has completed? I thought that using NSFileCoordinator would solve this issue, but unfortunately it's not the case. Since an unzip operation can last any amount of time, it's not ideal to just delay a sync by a fixed number of seconds and let the user deal with any error if the unzip operation takes longer. let openPanel = NSOpenPanel() openPanel.canChooseDirectories = true if openPanel.runModal() == .cancel { return } let url = openPanel.urls[0].appendingPathComponent("extracted", isDirectory: false) var error: NSError? NSFileCoordinator(filePresenter: nil).coordinate(readingItemAt: url, error: &error) { url in do { print(try FileManager.default.attributesOfItem(atPath: url.path).sorted(by: { $0.key.rawValue < $1.key.rawValue }).map({ ($0.key.rawValue, $0.value) })) try FileManager.default.contentsOfDirectory(at: url, includingPropertiesForKeys: nil) } catch { print(error) } } if let error = error { print("file coordinator error:", error) }

The online documentation for fs_snapshot_create, which is on a website which apparently I'm not allowed to link to on this forum, mentions that some entitlement is necessary, but doesn't specify which one. Searching online I found someone mentioning com.apple.developer.vfs.snapshot, but when adding this to my entitlement file and building my Xcode project, I get the error Provisioning profile "Mac Team Provisioning Profile: com.example.myApp" doesn't include the com.apple.developer.vfs.snapshot entitlement. Searching some more online, I found someone mentioning that one has to request this entitlement from DTS. Is this true? I couldn't find any official documentation. I actually want to make a snapshot of a user-selected directory so that my app can sync it to another volume while avoiding that the user makes changes during the sync process that would make the copy inconsistent. Would fs_snapshot_create be faster than traversing the chosen directory and creating clones of each nested file with filecopy and the flag COPYFILE_CLONE? Although I have the impression that only fs_snapshot_create could make a truly consistent snapshot.

In my app I have a background task performed on a custom DispatchQueue. When it has completed, I update the UI in DispatchQueue.main.async. In a particular case, the app then needs to show a modal window that contains a table view, but I have noticed that when scrolling through the tableview, it only responds very slowly. It appears that this happens when the table view in the modal window is presented in DispatchQueue.main.async. Presenting it in perform(_:with:afterDelay:) or in a Timer.scheduledTimer(withTimeInterval:repeats:block:) on the other hand works. Why? This seems like an ugly workaround. I created FB7448414 in November 2019 but got no response. @NSApplicationMain class AppDelegate: NSObject, NSApplicationDelegate { func applicationDidFinishLaunching(_ aNotification: Notification) { let windowController = NSWindowController(window: NSWindow(contentViewController: ViewController())) // 1. works // runModal(for: windowController) // 2. works // perform(#selector(runModal), with: windowController, afterDelay: 0) // 3. works // Timer.scheduledTimer(withTimeInterval: 0, repeats: false) { [self] _ in // self.runModal(for: windowController) // } // 4. doesn't work DispatchQueue.main.async { self.runModal(for: windowController) } } @objc func runModal(for windowController: NSWindowController) { NSApp.runModal(for: windowController.window!) } } class ViewController: NSViewController, NSTableViewDataSource, NSTableViewDelegate { override func loadView() { let tableView = NSTableView() tableView.dataSource = self tableView.delegate = self tableView.addTableColumn(NSTableColumn()) let scrollView = NSScrollView(frame: CGRect(x: 0, y: 0, width: 400, height: 400)) scrollView.documentView = tableView scrollView.hasVerticalScroller = true scrollView.translatesAutoresizingMaskIntoConstraints = false view = scrollView } func numberOfRows(in tableView: NSTableView) -> Int { return 100 } func tableView(_ tableView: NSTableView, viewFor tableColumn: NSTableColumn?, row: Int) -> NSView? { let view = NSTableCellView() let textField = NSTextField(labelWithString: "\(row)") textField.translatesAutoresizingMaskIntoConstraints = false view.addSubview(textField) NSLayoutConstraint.activate([textField.leadingAnchor.constraint(equalTo: view.leadingAnchor), textField.trailingAnchor.constraint(equalTo: view.trailingAnchor), textField.topAnchor.constraint(equalTo: view.topAnchor), textField.bottomAnchor.constraint(equalTo: view.bottomAnchor)]) return view } }

I noticed that sometimes TextKit2 decides to crop some text instead of soft-wrapping it to the next line. This can be reproduced by running the code below, then resizing the window by dragging the right margin to the right until you see the text with green background (starting with “file0”) at the end of the first line. If you now slowly move the window margin back to the left, you’ll see that for some time that green “file0” text is cropped and so is the end of the text with red background, until at some point it is soft-wrapped on the second line. I just created FB18289242. Is there a workaround? class ViewController: NSViewController { override func loadView() { let textView = NSTextView(frame: CGRect(x: 0, y: 0, width: 400, height: 400)) let string = NSMutableAttributedString(string: "file0\t143548282\t1970-01-01T00:00:00Z\t1\t1f40fc92da241694750979ee6cf582f2d5d7d28e18335de05abc54d0560e0f5302860c652bf08d560252aa5e74210546f369fbbbce8c12cfc7957b2652fe9a75", attributes: [.foregroundColor: NSColor.labelColor, .backgroundColor: NSColor.red.withAlphaComponent(0.2)]) string.append(NSAttributedString(string: "file0\t143548290\t1970-01-01T00:05:00Z\t 2\t0f6460d0ed7825fed6bda0f4d9c14942d88edc7ff236479212e69f081815e6f1742c272753b77cc6437f06ef93a46271c6ff9513c68945075212434080e60c82", attributes: [.foregroundColor: NSColor.labelColor, .backgroundColor: NSColor.green.withAlphaComponent(0.2)])) textView.textContentStorage!.textStorage!.setAttributedString(string) textView.autoresizingMask = [.width, .height] let scrollView = NSScrollView(frame: CGRect(x: 0, y: 0, width: 400, height: 400)) scrollView.documentView = textView scrollView.hasVerticalScroller = true scrollView.translatesAutoresizingMaskIntoConstraints = false view = scrollView } }

When I connect to another Mac via Finder (using SMB), creating a hard link with FileManager.linkItem(atPath:toPath:) fails (both source and destination are on the remote Mac). I read online that SMB itself supports creating hard links, so is this a macOS limitation or bug?

Until now I was using FileManager.contentsEqual(atPath:andPath:) to compare file contents in my App Store app, but then a user reported that this operation is way slower than just copying the files (which I made faster a while ago, as explained in Making filecopy faster by changing block size). I thought that maybe the FileManager implementation reads the two files with a small block size, so I implemented a custom comparison with the same block size I use for filecopy (as explained in the linked post), and it runs much faster. When using the code for testing repeatedly also found on that other post, this new implementation is about the same speed as FileManager for 1KB files, but runs 10-20x faster for 1MB files or bigger. Feel free to comment on my implementation below. extension FileManager { func fastContentsEqual(atPath path1: String, andPath path2: String, progress: (_ delta: Int) -> Bool) -> Bool { do { let bufferSize = 16_777_216 let sourceDescriptor = open(path1, O_RDONLY | O_NOFOLLOW, 0) if sourceDescriptor < 0 { throw NSError(domain: NSPOSIXErrorDomain, code: Int(errno)) } let sourceFile = FileHandle(fileDescriptor: sourceDescriptor) let destinationDescriptor = open(path2, O_RDONLY | O_NOFOLLOW, 0) if destinationDescriptor < 0 { throw NSError(domain: NSPOSIXErrorDomain, code: Int(errno)) } let destinationFile = FileHandle(fileDescriptor: destinationDescriptor) var equal = true while autoreleasepool(invoking: { let sourceData = sourceFile.readData(ofLength: bufferSize) let destinationData = destinationFile.readData(ofLength: bufferSize) equal = sourceData == destinationData return sourceData.count > 0 && progress(sourceData.count) && equal }) { } if close(sourceDescriptor) < 0 { throw NSError(domain: NSPOSIXErrorDomain, code: Int(errno)) } if close(destinationDescriptor) < 0 { throw NSError(domain: NSPOSIXErrorDomain, code: Int(errno)) } return equal } catch { return contentsEqual(atPath: path1, andPath: path2) // use this as a fallback for unsupported files (like symbolic links) } } }

A user of my app reported that when trying to remove a file it always fails with the error "file couldn't be removed because you don't have permission to access it (Cocoa Error Domain 513)". After some testing, we found out that it's caused by trying to delete non-empty directories. I'm using FileManager.removeItem(atPath:) which has worked fine for many years, but it seems that with their particular NAS, it doesn't work. I could work around this by checking if the file is a directory, and if it is, enumerating the directory and remove each contained file before removing the directory itself. But shouldn't this already be taken care of? In the source code of FileManager I see that for Darwin platforms it calls removefile(pathPtr, state, removefile_flags_t(REMOVEFILE_RECURSIVE)) so it seems that it should already work. Is the REMOVEFILE_RECURSIVE flag perhaps ignored by the device? But then, is the misleading "you don't have permission to access the file" error thrown by the device or by macOS? For the FileManager source code, see https://github.com/swiftlang/swift-foundation/blob/1d5d70997410fc8b7700c8648b10d6fc28194202/Sources/FoundationEssentials/FileManager/FileOperations.swift#L444

I successfully installed macOS Tahoe 26 in June on a separate external partition. Now I want to update to beta 5, but when the Mac restarts to install the update, it shows the progress indicator for a minute or two, then boots again into the main partition which has macOS 15.6. Am I required to install it from scratch?

A user of my AppKit, document-based app brought to my attention that when setting it as the default app to open a certain file with extension .md (by choosing in the Finder "File &gt; Open With &gt; Other", then selecting my app and enabling "Always open with"), trying to open it with a double-click displays the warning "Apple could not verify [file] is free of malware that may harm your mac or compromise your privacy". This is what happens for me: When keeping the default app for a .md file (Xcode in my case), the file opens just fine. When choosing my app in the "File &gt; Open With" menu, the file opens just fine in my app. But when setting my app as the default app (see above), the warning is displayed. From that moment on, choosing my app in the "File &gt; Open With" menu doesn't work anymore. Selecting Xcode doesn't work either. Only setting Xcode again as the default app allows me to open it in Xcode, but my app still isn't allowed to open it. Is this a macOS issue, or can I do anything in my app to prevent it? Where should I start looking for the issue in my code?

In my app I use AVAssetReaderTrackOutput to extract PCM audio from a user-provided video or audio file and display it as a waveform. Recently a user reported that the waveform is not in sync with his video, and after receiving the video I noticed that the waveform is in fact double as long as the video duration, i.e. it shows the audio in slow-motion, so to speak. Until now I was using CMFormatDescription.audioStreamBasicDescription.mSampleRate which for this particular user video returns 22'050. But in this case it seems that this value is wrong... because the audio file has two audio channels with different sample rates, as returned by CMFormatDescription.audioFormatList.map({ $0.mASBD.mSampleRate }) The first channel has a sample rate of 44'100, the second one 22'050. If I use the first sample rate, the waveform is perfectly in sync with the video. The problem is given by the fact that the ratio between the audio data length and the sample rate multiplied by the audio duration is 8, double the ratio for the first audio file (4). In the code below this ratio is given by Double(length) / (sampleRate * asset.duration.seconds) When commenting out the line with the sampleRate variable definition in the code below and uncommenting the following line, the ratios for both audio files are 4, which is the expected result. I would expect audioStreamBasicDescription to return the correct sample rate, i.e. the one used by AVAssetReaderTrackOutput, which (I think) somehow merges the stereo tracks. The documentation is sparse, and in particular it’s not documented whether the lower or higher sample rate is used; in this case, it seems like the higher one is used, but audioStreamBasicDescription for some reason returns the lower one. Does anybody know why this is the case or how I should extract the sample rate of the produced PCM audio data? Should I always take the higher one? I created FB19620455. let openPanel = NSOpenPanel() openPanel.allowedContentTypes = [.audiovisualContent] openPanel.runModal() let url = openPanel.urls[0] let asset = AVURLAsset(url: url) let assetTrack = asset.tracks(withMediaType: .audio)[0] let assetReader = try! AVAssetReader(asset: asset) let readerOutput = AVAssetReaderTrackOutput(track: assetTrack, outputSettings: [AVFormatIDKey: Int(kAudioFormatLinearPCM), AVLinearPCMBitDepthKey: 16, AVLinearPCMIsBigEndianKey: false, AVLinearPCMIsFloatKey: false, AVLinearPCMIsNonInterleaved: false]) readerOutput.alwaysCopiesSampleData = false assetReader.add(readerOutput) let formatDescriptions = assetTrack.formatDescriptions as! [CMFormatDescription] let sampleRate = formatDescriptions[0].audioStreamBasicDescription!.mSampleRate //let sampleRate = formatDescriptions[0].audioFormatList.map({ $0.mASBD.mSampleRate }).max()! print(formatDescriptions[0].audioStreamBasicDescription!.mSampleRate) print(formatDescriptions[0].audioFormatList.map({ $0.mASBD.mSampleRate })) if !assetReader.startReading() { preconditionFailure() } var length = 0 while assetReader.status == .reading { guard let sampleBuffer = readerOutput.copyNextSampleBuffer(), let blockBuffer = sampleBuffer.dataBuffer else { break } length += blockBuffer.dataLength } print(Double(length) / (sampleRate * asset.duration.seconds))

I have a table view where each row has two labels, one left-aligned and one right-aligned. I would like to reload a single row, but doing so causes the right-aligned label to hug the left-aligned label. Before the reload: After the reload: Reloading the whole table view instead, or disabling automatic row height, solves the issue. Can a single row be reloaded without resorting to these two workarounds? I created FB13534100 1.5 years ago but got no response. class ViewController: NSViewController, NSTableViewDataSource, NSTableViewDelegate { override func loadView() { let tableView = NSTableView() tableView.translatesAutoresizingMaskIntoConstraints = false tableView.dataSource = self tableView.delegate = self tableView.usesAutomaticRowHeights = true let column = NSTableColumn() column.width = 400 tableView.addTableColumn(column) let scrollView = NSScrollView(frame: CGRect(x: 0, y: 0, width: 500, height: 500)) scrollView.translatesAutoresizingMaskIntoConstraints = false scrollView.documentView = tableView view = scrollView Timer.scheduledTimer(withTimeInterval: 2, repeats: false) { _ in print("reload") tableView.reloadData(forRowIndexes: IndexSet(integer: 2), columnIndexes: IndexSet(integer: 0)) // tableView.reloadData() } } func numberOfRows(in tableView: NSTableView) -> Int { return 5 } func tableView(_ tableView: NSTableView, viewFor tableColumn: NSTableColumn?, row: Int) -> NSView? { let cell = NSTableCellView() let textField1 = NSTextField(labelWithString: "hello") textField1.translatesAutoresizingMaskIntoConstraints = false let textField2 = NSTextField(wrappingLabelWithString: "world") textField2.translatesAutoresizingMaskIntoConstraints = false textField2.alignment = .right let stack = NSStackView(views: [ textField1, textField2 ]) stack.translatesAutoresizingMaskIntoConstraints = false stack.distribution = .fill cell.addSubview(stack) NSLayoutConstraint.activate([stack.topAnchor.constraint(equalTo: cell.topAnchor, constant: 0), stack.leadingAnchor.constraint(equalTo: cell.leadingAnchor, constant: 0), stack.bottomAnchor.constraint(equalTo: cell.bottomAnchor, constant: 0), stack.trailingAnchor.constraint(equalTo: cell.trailingAnchor, constant: 0)]) return cell } }

A user of my app noticed that when using it to move a file to the trash on an USB drive, the trash doesn't show the file until unmounting the drive and mounting it again. I was able to reproduce it with one of my own USB drives, but with another USB drive it doesn't reproduce. All USB drives are formatted APFS. When moving a file to the trash from the Finder, both USB drives immediately list it in the trash. Is this a macOS bug, or am I doing something wrong? I created FB19941168. let openPanel = NSOpenPanel() openPanel.runModal() let url = openPanel.urls[0] do { var result: NSURL? try FileManager.default.trashItem(at: url, resultingItemURL: &result) print(result as Any) } catch { fatalError(error.localizedDescription) }

My app displays some text that should appear the same regardless of the container view or window size, i.e. it should grow and shrink with the container view or window. On iOS there is UILabel.adjustsFontSizeToFitWidth but I couldn't find any equivalent API on macOS. On the internet some people suggest to iteratively set a smaller font size until the text fits the available space, but I thought there must be a more efficient solution. How does UILabel.adjustsFontSizeToFitWidth do it? My expectation was that setting a font's size to a fraction of the window width or height would do the trick, but when resizing the window I can see a slightly different portion of it. class ViewController: NSViewController { override func loadView() { view = MyView(frame: CGRect(x: 0, y: 0, width: 400, height: 400)) NSLayoutConstraint.activate([view.widthAnchor.constraint(equalTo: view.heightAnchor, multiplier: 3), view.heightAnchor.constraint(greaterThanOrEqualToConstant: 100)]) } } class MyView: NSView { let textField = NSTextField(labelWithString: String(repeating: "a b c d e f g h i j k l m n o p q r s t u v w x y z ", count: 2)) override init(frame frameRect: NSRect) { super.init(frame: frameRect) textField.translatesAutoresizingMaskIntoConstraints = false textField.setContentCompressionResistancePriority(.defaultLow, for: .horizontal) addSubview(textField) NSLayoutConstraint.activate([textField.topAnchor.constraint(equalTo: topAnchor), textField.leadingAnchor.constraint(equalTo: leadingAnchor), textField.trailingAnchor.constraint(equalTo: trailingAnchor)]) } required init?(coder: NSCoder) { fatalError("init(coder:) has not been implemented") } override func resize(withOldSuperviewSize oldSize: NSSize) { // textField.font = .systemFont(ofSize: frame.width * 0.05) textField.font = .systemFont(ofSize: frame.height * 0.1) } }

A user of my app brought to my attention that unless they select their ~/Library/Mail folder explicitly in an open panel, they get an error when scanning it inside my app. I can confirm that I also get a permission error when trying to scan it as a subfolder of ~/Library, but not if I select it directly. I'm assuming this is intentional, but it would be nice to have an explanation or some documentation that I can point my users to when they encounter what appears to them as a bug in my app. What makes this matter even more confusing is that selecting a folder in any open panel of an app gives the app access to it for the lifetime of the app, but after restarting the app, access is lost again (unless it has a bookmark to it). This was probably the reason why the user thought that it worked in another app but not in mine. This is the code I use to scan: let openPanel = NSOpenPanel() openPanel.canChooseDirectories = true if openPanel.runModal() == .cancel { return } let enumerator = FileManager.default.enumerator(at: openPanel.urls[0], includingPropertiesForKeys: nil) { url, error in print(url.path, error) return true } while let url = enumerator?.nextObject() as? URL { } And this the error related to the Mail folder: ~/Library/Mail Error Domain=NSCocoaErrorDomain Code=257 "The file “Mail” couldn’t be opened because you don’t have permission to view it." UserInfo={NSURL=file:///~/Library/Mail, NSFilePath=/~/Library/Mail, NSUnderlyingError=0x600002991470 {Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"}}

In the past I was always able to install every major macOS version on an external drive so that I can test my apps. But now I'm unable to install macOS Tahoe 26 on an external drive. Actually, as far as I'm aware, there are not even official links to macOS 26 installers, but only instructions on how to update to macOS 26 from an existing macOS installation. So I thought I'd install macOS 15 on a separate drive and then update to macOS 26, but whenever I run the macOS 15 installer, tell it to install on the external drive, and reboot after the setup process completes, my MacBook just boots into my main macOS partition as if nothing happened. 3 months ago I somehow managed to install macOS Tahoe beta 1 on an external drive, I don't remember how (but I don't think it was anything crazy); booting into that beta 1 partition and trying to update doesn't work either, as my MacBook again boots into my main macOS partition. I already asked help about the update problem one month ago here, but nobody replied. Could someone at Apple please provide instructions on how one is supposed to install macOS 26 on an external drive (if possible before it becomes available to the public)? Are we supposed to buy a separate Mac for every macOS version that we want to test our apps on?