My app saves its document files by default into ~/Documents. It does some important domain-specific stuff when a document is deleted. I monitor for deletion using https://github.com/eonist/FileWatcher
Unfortunately several users have noticed my app doing this cleanup work even when they have not deleted the corresponding document. We've traced it through and realised it's the iCloud "Optimise Mac Storage" feature, or "Store in iCloud > Desktop and Documents". I'm not sure which because I don't use these features of macOS at all, and also they seem to have been renamed or changed in Sonoma.
Either way, I'm wondering:
a) how I can tell in Swift whether a file has actually been deleted, or whether it's been "offloaded" to iCloud by macOS.
b) how can I test this?
My research is pointing at urlubiquitousitemdownloadingstatus but it's hard to play with it without knowing how to test it.
Files and Storage
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Hi, I'm working with UIDocument to store a PDF file. This is code I use for saving a file.
document.close(completionHandler: { (success) in
if success {
document.save(to: url,
for: .forOverwriting,
completionHandler: { (success) in
if success {
print("Saved file successfully")
}
})
}
})
This code works well with a small file size. But if it's a large file like 100MB, it takes around 2-5 minutes to save the file. Is there a way to save file with the changes only? Or create an auto save function triggered whenever the user edit the file?
Hello,
I'm facing a weird issue when application bundle is corrupted during installation. The corruption always look the same - a certain sequence of bytes is erased (zeroed) in the file at multiple places, which obviously breaks the bundle signature.
It's a pkg built with productbuild, containing three component packages, up until recently no issue occurred. Everything is correctly signed and notarized and I don't do anything special in preinstall or postinstall scripts but I run gktool scan which reports "Scan completed, but failed because the software has been altered" which makes me believe that bundle is corrupted during installation or decompression. I'm using --compression latest for the bundle's component package.
I don't have a reliable repro but I see it happen a lot to our customers. I was suspecting a deployment tool or "security software" but I've seen the issue for manually installed packages too. It seems it happens only on Sonoma, but that may be related to fact most users are on latest macOS.
Is there any known issue with installer which could lead to bundle being corrupted this way? Did anyone faced anything similar?
Under Ventura, desktop wallpaper image names were stored in a sqlite database at ~/Library/Application Support/Dock/desktoppicture.db. This file is no longer being used under Sonoma.
I have a process I built that fetches the desktop image file names and displays them, either as a service, or on the desktop. I do this because I have many photos I've taken, and I like to know which one I'm viewing so I can make edits if necessary. I set these images across five spaces and have them randomly change every hour. I tried using AppleScript but it would not pull the file names.
A few people have pointed me to ~/Library/Application Support/com.apple.wallpaper/Store/Index.plist. However, on my system, this only reveals the source folder and not the image name itself. On one of my Macs, it shows 64 items, even though I have only five spaces!
Is there a way to fetch the image file names under Sonoma? Will Sequoia make this easier or harder?
Topic:
App & System Services
SubTopic:
General
Tags:
macOS
Photos and Imaging
AppleScript
Files and Storage
I'm just trying to display an image that is stored in the local filesystem, but the more I dig into this the more confused I get.
So previously I used this code (it's simplified):
func findImage(name: String) -> UIImage? {
do {
let url = try FileManager.default.url(for: .applicationSupportDirectory,
in: .userDomainMask,
appropriateFor: nil,
create: false)
.appendingPathComponent("MyFolder")
.appendingPathComponent("\(name).png")
guard let image = UIImage(contentsOfFile: url.path) else {
return nil
}
return image
} catch {
print(error.localizedDescription)
}
return nil
}
Notice I create the URL with just .appendingPathComponent() and turning URL to path via url.path.
It works! So what's the question?
In Improving performance and stability when accessing the file system I've read that you better use the new appendingPathComponent(_:isDirectory:), that's good, will do.
Also url.path is deprecated in iOS18. Should I use url.path(percentEncoded:) instead? What should be the value of percentEncoded when accessing the local filesystem?
In this adjacent thread I've read:
Don't use UIImage(contentsOfFile:) either, because it's a path-based API. There's no URL-based equivalent, which is an Apple clue that should be doing something else.
Is this true? Then how should I store and load my images?
Just FYI, I create images like this:
private func generateThumbnail(name: String) {
guard let drawingWidth = canvasGeo?.size.width,
let drawingHeight = canvasGeo?.size.height else { return }
let thumbnailRect = CGRect(x: 0, y: 0, width: drawingWidth, height: drawingHeight)
Task {
UITraitCollection(userInterfaceStyle: .light).performAsCurrent {
let image = self.canvasView.drawing.image(from: thumbnailRect, scale: UIScreen.main.scale)
guard let data = image.pngData() else { return } // -- HERE
do {
try FileManager.default.createDirectory(at: try FileManager.default.url(for: .applicationSupportDirectory,
in: .userDomainMask,
appropriateFor: nil,
create: true)
.appendingPathComponent("MyFolder"),
withIntermediateDirectories: true,
attributes: nil)
let filename = "\(name).png"
let url = try FileManager.default.url(for: .applicationSupportDirectory,
in: .userDomainMask,
appropriateFor: nil,
create: true)
.appendingPathComponent("MyFolder")
.appendingPathComponent(filename)
try data.write(to: url, options: .atomic) // -- and HERE
} catch {
print(error.localizedDescription)
}
}
}
}
My usecase — just save the user's PencilKit Canvas as an image and display it back to him on a different View. I'm on SwiftUI and iOS 16+.
Would be happy to learn the correct way, thanks!
I am working on an iOS application using SwiftUI where I want to convert a JPG and a MOV file to a live photo. I am utilizing the LivePhoto Class from Github for this. The JPG and MOV files are displayed correctly in my WallpaperDetailView, but I am facing issues when trying to download the live photo to the gallery and generate the Live Photo.
Here is the relevant code and the errors I am encountering:
Console prints:
Play button should be visible Image URL fetched and set: Optional("https://firebasestorage.googleapis.com/...") Video is ready to play Video downloaded to: file:///var/mobile/Containers/Data/Application/.../tmp/CFNetworkDownload_7rW5ny.tmp Failed to generate Live Photo
I have verified that the app has the necessary permissions to access the Photo Library.
The JPEG and MOV files are successfully downloaded and can be displayed in the app.
The issue seems to occur when generating the Live Photo from the downloaded files.
struct WallpaperDetailView: View {
var wallpaper: Wallpaper
@State private var isLoading = false
@State private var isImageSaved = false
@State private var imageURL: URL?
@State private var livePhotoVideoURL: URL?
@State private var player: AVPlayer?
@State private var playerViewController: AVPlayerViewController?
@State private var isVideoReady = false
@State private var showBuffering = false
var body: some View {
ZStack {
if let imageURL = imageURL {
GeometryReader { geometry in
KFImage(imageURL)
.resizable()
...
}
}
if let playerViewController = playerViewController {
VideoPlayerViewController(playerViewController: playerViewController)
.frame(maxWidth: .infinity, maxHeight: .infinity)
.clipped()
.edgesIgnoringSafeArea(.all)
}
}
.onAppear {
PHPhotoLibrary.requestAuthorization { status in
if status == .authorized {
loadImage()
} else {
print("User denied access to photo library")
}
}
}
private func loadImage() {
isLoading = true
if let imageURLString = wallpaper.imageURL, let imageURL = URL(string: imageURLString) {
self.imageURL = imageURL
if imageURL.scheme == "file" {
self.isLoading = false
print("Local image URL set: \(imageURL)")
} else {
fetchDownloadURL(from: imageURLString) { url in
self.imageURL = url
self.isLoading = false
print("Image URL fetched and set: \(String(describing: url))")
}
}
}
if let livePhotoVideoURLString = wallpaper.livePhotoVideoURL, let livePhotoVideoURL = URL(string: livePhotoVideoURLString) {
self.livePhotoVideoURL = livePhotoVideoURL
preloadAndPlayVideo(from: livePhotoVideoURL)
} else {
self.isLoading = false
print("No valid image or video URL")
}
}
private func preloadAndPlayVideo(from url: URL) {
self.player = AVPlayer(url: url)
let playerViewController = AVPlayerViewController()
playerViewController.player = self.player
self.playerViewController = playerViewController
let playerItem = AVPlayerItem(url: url)
playerItem.preferredForwardBufferDuration = 1.0
self.player?.replaceCurrentItem(with: playerItem)
...
print("Live Photo Video URL set: \(url)")
}
private func saveWallpaperToPhotos() {
if let imageURL = imageURL, let livePhotoVideoURL = livePhotoVideoURL {
saveLivePhotoToPhotos(imageURL: imageURL, videoURL: livePhotoVideoURL)
} else if let imageURL = imageURL {
saveImageToPhotos(url: imageURL)
}
}
private func saveImageToPhotos(url: URL) {
...
}
private func saveLivePhotoToPhotos(imageURL: URL, videoURL: URL) {
isLoading = true
downloadVideo(from: videoURL) { localVideoURL in
guard let localVideoURL = localVideoURL else {
print("Failed to download video for Live Photo")
DispatchQueue.main.async {
self.isLoading = false
}
return
}
print("Video downloaded to: \(localVideoURL)")
self.generateAndSaveLivePhoto(imageURL: imageURL, videoURL: localVideoURL)
}
}
private func generateAndSaveLivePhoto(imageURL: URL, videoURL: URL) {
LivePhoto.generate(from: imageURL, videoURL: videoURL, progress: { percent in
print("Progress: \(percent)")
}, completion: { livePhoto, resources in
guard let resources = resources else {
print("Failed to generate Live Photo")
DispatchQueue.main.async {
self.isLoading = false
}
return
}
print("Live Photo generated with resources: \(resources)")
self.saveLivePhotoToLibrary(resources: resources)
})
}
private func saveLivePhotoToLibrary(resources: LivePhoto.LivePhotoResources) {
LivePhoto.saveToLibrary(resources) { success in
DispatchQueue.main.async {
if success {
self.isImageSaved = true
print("Live Photo saved successfully")
} else {
print("Failed to save Live Photo")
}
self.isLoading = false
}
}
}
private func fetchDownloadURL(from gsURL: String, completion: @escaping (URL?) -> Void) {
let storageRef = Storage.storage().reference(forURL: gsURL)
storageRef.downloadURL { url, error in
if let error = error {
print("Failed to fetch image URL: \(error)")
completion(nil)
} else {
completion(url)
}
}
}
private func downloadVideo(from url: URL, completion: @escaping (URL?) -> Void) {
let task = URLSession.shared.downloadTask(with: url) { localURL, response, error in
guard let localURL = localURL, error == nil else {
print("Failed to download video: \(String(describing: error))")
completion(nil)
return
}
completion(localURL)
}
task.resume()
}
}```
Topic:
Media Technologies
SubTopic:
Photos & Camera
Tags:
Files and Storage
Swift
SwiftUI
Photos and Imaging
I have an app (currently not released on App Store) which runs on both iOS and macOS. The app has widgets for both iOS and macOS which uses user preference (set in app) into account while showing data. Before upgrading to macOS 15 (until Sonoma) widgets were working fine and app was launching correctly, but after upgrading to macOS 15 Sequoia, every time I launch the app it give popup saying '“Kontest” would like to access data from other apps. Keeping app data separate makes it easier to manage your privacy and security.' and also widgets do not get user preferences and throw the same type of error on Console application when using logging. My App group for both iOS and macOS is 'group.com.xxxxxx.yyyyy'. I am calling it as 'UserDefaults(suiteName: Constants.userDefaultsGroupID)!.bool(forKey: "shouldFetchAllEventsFromCalendar")'. Can anyone tell, what am I doing wrong here?
I'm an iOS developer, and I've been testing our app in iOS 18.0 Beta. I noticed that there's a problem with the font rendering, and after troubleshooting, I've found out that it's caused by the removal of the PingFang.ttc font in 18.0.
I would like to ask the reason for removing this font file and which font should be used to display Chinese in the future?
My test device is an iPhone 11 Pro and the system version is iOS 18.0 (22A5297). I have also tested Beta 1 and it has the same issue.
In previous versions of the system, the PingFang font is located in this directory /System/Library/Fonts/LanguageSupport/PingFang.ttc. But in iOS 18.0, the font file in this directory has become Kohinoor.ttc, and I've tested that this font can't display Chinese either.
I traversed the following system font directories and could not find the PingFang.ttc font file.
/System/Library/Fonts/AppFonts
/System/Library/Fonts/Core
/System/Library/Fonts/CoreAddition
/System/Library/Fonts/CoreUI
/System/Library/Fonts/LanguageSupport
/System/Library/Fonts/UnicodeSupport
/System/Library/Fonts/Watch
Looking for answers, thanks for the help!
I'm creating an App that can accepted PDFs from a shared context.
I am using iOS, Swift, and UIKit with IOS 17.1+
The logic is:
get the context
see who is sending in (this is always unknown)
see if I can open in place (in case I want to save later)
send the URL off to open the (PDF) document and
load it into PDFKit's pdfView.document
I have no trouble loading PDF docs with the file picker.
And everything works as expected for shares from apps like Messages, email, etc... (in which case URLContexts.first.options.openInPlace == False)
The problem is with opening (sharing) a PDF that is sent from the Files App. (openInPlace == True)
If the PDF is in the App's Document Folder, I need the Security scoped resource, to access the URL from the File's App so that I can copy the PDF's data to the PDFViewer.document. I get Security scoped resource access granted each time I get the File App's context URL.
But, when I call fileCoordinator.coordinate and try to access a file outside of the App's document folder using the newUrl, I get an error.
FYI - The newUrl (byAccessor) and context url (readingItemAt) paths are always same for the Files App URL share context.
I can, however, copy the file to a new location in my apps directory and then open it from there and load in the data. But I really do not want to do that.
. . . . .
Questions:
Am I missing something in my pList or are there other parameters specific to sharing a file from the Files App?
I'd appreciate if someone shed some light on this?
. . . . .
Here are the parts of my code related to this with some print statements...
. . . . .
SceneDelegate
func scene(_ scene: UIScene, openURLContexts URLContexts: Set<UIOpenURLContext>) {
// nothing to see here, move along
guard let urlContext = URLContexts.first else {
print("No URLContext found")
return
}
// let's get the URL (it will be a PDF)
let url = urlContext.url
let openInPlace = urlContext.options.openInPlace
let bundleID = urlContext.options.sourceApplication
print("Triggered with URL: \(url)")
print("Can Open In Place?: \(openInPlace)")
print("For Bundle ID: \(bundleID ?? "None")")
// get my Root ViewController from window
if let rootViewController = self.window?.rootViewController {
// currently using just the view
if let targetViewController = rootViewController as? ViewController {
targetViewController.prepareToLoadSharedPDFDocument(at: url)
}
// I might use a UINavigationController in the future
else if let navigationController = rootViewController as? UINavigationController,
let targetViewController = navigationController.viewControllers.first as? ViewController {
targetViewController.prepareToLoadSharedPDFDocument(at: url)
}
}
}
. . . .
ViewController function
I broke out the if statement for accessingScope just to make it easier for me the debug and play around with the code in accessingScope == True
func loadPDF(fromUrl url: URL) {
// If using the File Picker / don't use this
// If going through a Share.... we pass the URL and have three outcomes (1, 2a, 2b)
// 1. Security scoped resource access NOT needed if from a Share Like Messages or EMail
// 2. Security scoped resource access granted/needed from 'Files' App
// a. success if in the App's doc directory
// b. fail if NOT in the App's doc directory
// Set the securty scope variable
var accessingScope = false
// Log the URLs for debugging
print("URL String: \(url.absoluteString)")
print("URL Path: \(url.path())")
// Check if the URL requires security scoped resource access
if url.startAccessingSecurityScopedResource() {
accessingScope = true
print("Security scoped resource access granted.")
} else {
print("Security scoped resource access denied or not needed.")
}
// Stop accessing the scope once everything is compeleted
defer {
if accessingScope {
url.stopAccessingSecurityScopedResource()
print("Security scoped resource access stopped.")
}
}
// Make sure the file is still there (it should be in this case)
guard FileManager.default.fileExists(atPath: url.path) else {
print("File does not exist at URL: \(url)")
return
}
// Let's see if we can open it in place
if accessingScope {
let fileCoordinator = NSFileCoordinator()
var error: NSError?
fileCoordinator.coordinate(readingItemAt: url, options: [], error: &error) { (newUrl) in
DispatchQueue.main.async {
print(url.path())
print(newUrl.path())
if let document = PDFDocument(url: newUrl) {
self.pdfView.document = document
self.documentFileName = newUrl.deletingPathExtension().lastPathComponent
self.fileLoadLocation = newUrl.path()
self.updateGUI(pdfLoaded: true)
self.setPDFScale(to: self.VM.pdfPageScale, asNewPDF: true)
} else {
print("Could not load PDF directly from url: \(newUrl)")
}
}
}
if let error = error {
PRINT("File coordination error: \(error)")
}
} else {
DispatchQueue.main.async {
if let document = PDFDocument(url: url) {
self.pdfView.document = document
self.documentFileName = url.deletingPathExtension().lastPathComponent
self.fileLoadLocation = url.path()
self.updateGUI(pdfLoaded: true)
self.setPDFScale(to: self.VM.pdfPageScale, asNewPDF: true)
} else {
PRINT("Could not load PDF from url: \(url)")
}
}
}
}
. . . .
Other relevant pList settings I've added are:
Supports opening documents in place - YES
Document types - PDFs (com.adobe.pdf)
UIDocumentBrowserRecentDocumentContentTypes - com.adobe.pdf
Application supports iTunes file sharing - YES
And iCloud is one for Entitlements with
iCloud Container Identifiers
Ubiquity Container Identifiers
. . . .
Thank you in advance!.
B
If I drag something into my SwiftUI Mac app the .dropDestination gets an array of URLs that I can do with what I want.
If I use .fileImporter to get an identical array of URLs I should wrap start/stop securityScopedResource() calls around each URL before I do anything with it.
Can anyone explain the logic behind that? Is there some reason I'm not seeing? It is especially annoying in that the requirement for security scoping also doesn't exist if I use an NSOpenPanel instead of .fileImporter.
Hello everybody,
I am struggling with accessing files from the Location OneDrive through UIDocumentViewController.
The error says:
Error Domain=NSCocoaErrorDomain Code=260 "Die Datei „Testfile.txt“ konnte nicht geöffnet werden, da sie nicht existiert." UserInfo={NSFilePath=/private/var/mobile/Containers/Shared/AppGroup/11E04153-649E-416F-9860-2EA9C0913A18/File Provider Storage/item|1|18a17c69%2D5d6d%2D4b16%2Db388%2D4a9834e9440b/Testfile.txt, NSUnderlyingError=0x281202310 {Error Domain=NSPOSIXErrorDomain Code=2 "No such file or directory"}}
The Controller is initialised the following way:
let ctrl = UIDocumentPickerViewController(forOpeningContentTypes: [.image, .audio, .video, .item, .content])
And in the delegate method I do the following:
func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentsAt urls: [URL]) {
guard let documentUrl = urls.first else { return }
guard documentUrl.startAccessingSecurityScopedResource() else {
parent.errorText = "Developer Error: Can't access security scoped resource."
return
}
defer {
documentUrl.stopAccessingSecurityScopedResource()
}
do {
let data = try Data(contentsOf: documentUrl)
} catch {
parent.errorText = error.localizedDescription
}
}
Any help is appreciated!
Thanks
I like to find a way to identify network volumes, and whether they're run by certain servers, e.g. specifically whether they're on a Synology NAS.
Reason is that Synology, while apparently supporting the Spotlight-over-SMB API, comes with a lot of bugs, requiring me to work around them when searching on those volumes with the macOS Spotlight API.
I could, of course, ask the user to "configure" each mounted volume in my software, but I'd rather do this automagically, if possible, as it's less prone to user mistakes.
So, my question is: Is there a way to learn a bit more about the server of a mounted network volume? E.g., if I could learn its IP address, I could try to connect to it via http protocol and then maybe get a useful response that identifies it as being from Synology.
Or, alternatively, can I tell which SMB volumes are served by a Mac, so that I can at least assume that those handle Spotlight calls correctly, while I assume anything else is buggy (so far, AFAIK, Synology is the only other SMB server that supports Spotlight search).
I've tried to find some data in the IORegistry, but that doesn't seem to store anything about network vols. The statfs function doesn't seem to give me anything for that either, nor do the various fcntl calls as far as I could tell.
I also checked with the DA apis, e.g.:
DASessionRef daSession = DASessionCreate (NULL);
CFURLRef furl = CFURLCreateWithFileSystemPath(NULL, CFSTR("/Volumes/TheNAS"), kCFURLPOSIXPathStyle, true);
DADiskRef daDisk = DADiskCreateFromVolumePath (NULL, daSession, furl);
if (daDisk) {
CFDictionaryRef daInfo = DADiskCopyDescription (daDisk);
NSLog(@"%@", daInfo);
}
However, this only prints basic information:
DAVolumeKind = smbfs;
DAVolumeMountable = 1;
DAVolumeName = TheNAS;
DAVolumeNetwork = 1;
DAVolumePath = "file:///Volumes/TheNAS/";
Where, then, does Finder's "Get Info" get the smb path from, for example?
It seems that whenever I scan the contents of ~/Library/Containers with my app, I get the warning [App] would like to access data from other apps, regardless of how often I have already allowed it. When the warning appears, the last scanned file is ~/Library/Containers/com.apple.CloudPhotosConfiguration/Data.
My sample code:
let openPanel = NSOpenPanel()
openPanel.canChooseDirectories = true
openPanel.runModal()
let url = openPanel.urls[0]
let enumerator = FileManager.default.enumerator(at: url, includingPropertiesForKeys: nil)
while let url = enumerator?.nextObject() as? URL {
print(url.path)
}
Is it expected that one has to allow this warning every time the app is run?
Hi!
I have two problems with FileImport and FileExporter
Every time the file modal has been closed I get in the console this error/warning
[DocumentManager] The view service did terminate with error: Error Domain=_UIViewServiceErrorDomain Code=1 "(null)" UserInfo={Terminated=disconnect method}
The modal for FileExporter shows the label "Move", why? I'm creating a new file, not moving an existing one, since there is already the modifier FileMover. Is it correct? Can't be confusing for a user to see the label "Move"? Am I using it in the wrong way?
Can please someone help me with these two problems?
I'm using UIDocumentPickerViewController to open a url. Works fine in debug mode but version on the App Store is failing.
Code to create the document picker is like:
NSArray *theTypes = [UTType typesWithTag:@"docxtensionhere" tagClass:UTTagClassFilenameExtension conformingToType:nil];
UIDocumentPickerViewController *documentPicker = [[UIDocumentPickerViewController alloc]initForOpeningContentTypes:theTypes];
documentPicker.delegate = self;
[self presentViewController:documentPicker animated:YES completion:nil];
So in debug mode this is all gravy. -documentPicker:didPickDocumentsAtURLs: passes back a URL and I can read the file.
In release mode I get a URL but my app is denied access to read the file. After inspecting some logging it appears the sandbox is not granting my app permission.
error Domain=NSCocoaErrorDomain Code=257 "The file “Filename.fileextensionhere” couldn’t be opened because you don’t have permission to view it." UserInfo={NSFilePath=/private/var/mobile/Library/Mobile Documents/comappleCloudDocs/Filename.fileextensionhere, NSUnderlyingError=0x2834c9da0 {Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"}}
--
If I'm doing something wrong with UIDocumentPickerViewController it is a real shame that permission is not being denied in Debug mode, as devs are more likely to catch in prior to release. Anyone know where I'm going wrong and if not have a workaround? Thanks in advance.
General:
Forums subtopic: App & System Services > Core OS
Forums tags: Files and Storage, Foundation, FSKit, File Provider, Finder Sync, Disk Arbitration, APFS
Foundation > Files and Data Persistence documentation
Low-level file system APIs are documented in UNIX manual pages
File System Programming Guide archived documentation
About Apple File System documentation
Apple File System Guide archived documentation
File system changes introduced in iOS 17 forums post
On File System Permissions forums post
Extended Attributes and Zip Archives forums post
Unpacking Apple Archives forums post
Creating new file systems:
FSKit framework documentation
File Provider framework documentation
Finder Sync framework documentation
App Extension Programming Guide > App Extension Types > Finder Sync archived documentation
Managing storage:
Disk Arbitration framework documentation
Disk Arbitration Programming Guide archived documentation
Mass Storage Device Driver Programming Guide archived documentation
Device File Access Guide for Storage Devices archived documentation
BlockStorageDeviceDriverKit framework documentation
Volume format references:
Apple File System Reference
TN1150 HFS Plus Volume Format
Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"
I'm working on a macOS app that I want to give "Full Disk Access". When I run from Xcode, I get "permission denied" errors when reading a file in my home directory.
What can I do so that I can run and debug from Xcode?
I dragged the binary from the derived data folder to the System Preferences list for Full Disk Access, but that seems to do nothing.
I'm using UIDocumentPickerViewController to import document to my app from OneDrive and I want to show the OneDrive folder every time I use UIDocumentPickerViewController instead of the last folder I opened. Is it possible? Can I use pickerController.directoryURL ? And how to get folder URL of OneDrive?
class ViewController: UIViewController, DocumentDelegate {
var picker: DocumentPicker?
override func viewDidLoad() {
super.viewDidLoad()
picker = DocumentPicker(presentationController: self, delegate: self)
}
@IBAction func create_picker(_ sender: Any) {
picker?.presentDocumentPicker()
}
func didPickImage(image: UIImage?) {}
}
protocol DocumentDelegate: AnyObject {
func didPickImage(image: UIImage?)
}
class DocumentPicker: NSObject {
private var pickerController: UIDocumentPickerViewController?
private weak var presentationController: UIViewController?
private weak var delegate: DocumentDelegate?
init(presentationController: UIViewController,
delegate: DocumentDelegate) {
super.init()
self.presentationController = presentationController
self.delegate = delegate
}
func presentDocumentPicker() {
pickerController = UIDocumentPickerViewController(forOpeningContentTypes: [.image])
if let pickerController = pickerController {
pickerController.delegate = self
pickerController.allowsMultipleSelection = false
presentationController?.present(pickerController, animated: true)
}
}
}
extension DocumentPicker: UIDocumentPickerDelegate {
func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentsAt urls: [URL]) {
guard let url = urls.first else { return }
print(url)
}
}
Modern versions of macOS use a file system permission model that’s far more complex than the traditional BSD rwx model, and this post is my attempt at explaining that model. If you have a question about this, post it here on DevForums. Put your thread in the App & System Services > Core OS topic area and tag it with Files and Storage.
Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"
On File System Permissions
Modern versions of macOS have four different file system permission mechanisms:
Traditional BSD permissions
Access control lists (ACLs)
App Sandbox
Mandatory access control (MAC)
The first two were introduced a long time ago and rarely trip folks up. The second two are newer, more complex, and specific to macOS, and thus are the source of some confusion. This post is my attempt to clear that up.
Error Codes
App Sandbox and the mandatory access control system are both implemented using macOS’s sandboxing infrastructure. When a file system operation fails, check the error to see whether it was blocked by this sandboxing infrastructure. If an operation was blocked by BSD permissions or ACLs, it fails with EACCES (Permission denied, 13). If it was blocked by something else, it’ll fail with EPERM (Operation not permitted, 1).
If you’re using Foundation’s FileManager, these error are both reported as Foundation errors, for example, the NSFileReadNoPermissionError error. To recover the underlying error, get the NSUnderlyingErrorKey property from the info dictionary.
App Sandbox
File system access within the App Sandbox is controlled by two factors. The first is the entitlements on the main executable. There are three relevant groups of entitlements:
The com.apple.security.app-sandbox entitlement enables the App Sandbox. This denies access to all file system locations except those on a built-in allowlist (things like /System) or within the app’s containers.
The various “standard location” entitlements extend the sandbox to include their corresponding locations.
The various “file access temporary exceptions” entitlements extend the sandbox to include the items listed in the entitlement.
Collectively this is known as your static sandbox.
The second factor is dynamic sandbox extensions. The system issues these extensions to your sandbox based on user behaviour. For example, if the user selects a file in the open panel, the system issues a sandbox extension to your process so that it can access that file. The type of extension is determined by the main executable’s entitlements:
com.apple.security.files.user-selected.read-only results in an extension that grants read-only access.
com.apple.security.files.user-selected.read-write results in an extension that grants read/write access.
Note There’s currently no way to get a dynamic sandbox extension that grants executable access. For all the gory details, see this post.
These dynamic sandbox extensions are tied to your process; they go away when your process terminates. To maintain persistent access to an item, use a security-scoped bookmark. See Accessing files from the macOS App Sandbox. To pass access between processes, use an implicit security scoped bookmark, that is, a bookmark that was created without an explicit security scope (no .withSecurityScope flag) and without disabling the implicit security scope (no .withoutImplicitSecurityScope flag)).
If you have access to a directory — regardless of whether that’s via an entitlement or a dynamic sandbox extension — then, in general, you have access to all items in the hierarchy rooted at that directory. This does not overrule the MAC protection discussed below. For example, if the user grants you access to ~/Library, that does not give you access to ~/Library/Mail because the latter is protected by MAC.
Finally, the discussion above is focused on a new sandbox, the thing you get when you launch a sandboxed app from the Finder. If a sandboxed process starts a child process, that child process inherits its sandbox from its parent. For information on what happens in that case, see the Note box in Enabling App Sandbox Inheritance.
IMPORTANT The child process inherits its parent process’s sandbox regardless of whether it has the com.apple.security.inherit entitlement. That entitlement exists primarily to act as a marker for App Review. App Review requires that all main executables have the com.apple.security.app-sandbox entitlement, and that entitlements starts a new sandbox by default. Thus, any helper tool inside your app needs the com.apple.security.inherit entitlement to trigger inheritance. However, if you’re not shipping on the Mac App Store you can leave off both of these entitlement and the helper process will inherit its parent’s sandbox just fine. The same applies if you run a built-in executable, like /bin/sh, as a child process.
When the App Sandbox blocks something, it typically generates a sandbox violation report. For information on how to view these reports, see Discovering and diagnosing App Sandbox violations.
To learn more about the App Sandbox, see the various links in App Sandbox Resources. For information about how to embed a helper tool in a sandboxed app, see Embedding a Command-Line Tool in a Sandboxed App.
Mandatory Access Control
Mandatory access control (MAC) has been a feature of macOS for many releases, but it’s become a lot more prominent since macOS 10.14. There are many flavours of MAC but the ones you’re most likely to encounter are:
Full Disk Access (macOS 10.14 and later)
Files and Folders (macOS 10.15 and later)
App container protection (macOS 14 and later)
App group container protection (macOS 15 and later)
Data Vaults (see below) and other internal techniques used by various macOS subsystems
Mandatory access control, as the name suggests, is mandatory; it’s not an opt-in like the App Sandbox. Rather, all processes on the system, including those running as root, as subject to MAC.
Data Vaults are not a third-party developer opportunity. See this post if you’re curious.
In the Full Disk Access and Files and Folders cases, users grant a program a MAC privilege using System Settings > Privacy & Security. Some MAC privileges are per user (Files and Folders) and some are system wide (Full Disk Access). If you’re not sure, run this simple test:
On a Mac with two users, log in as user A and enable the MAC privilege for a program.
Now log in as user B. Does the program have the privilege?
If a process tries to access an item restricted by MAC, the system may prompt the user to grant it access there and then. For example, if an app tries to access the desktop, you’ll see an alert like this:
“AAA” would like to access files in your Desktop folder.
[Don’t Allow] [OK]
To customise this message, set Files and Folders properties in your Info.plist.
This system only displays this alert once. It remembers the user’s initial choice and returns the same result thereafter. This relies on your code having a stable code signing identity. If your code is unsigned, or signed ad hoc (“Signed to Run Locally” in Xcode parlance), the system can’t tell that version N+1 of your code is the same as version N, and thus you’ll encounter excessive prompts.
Note For information about how that works, see TN3127 Inside Code Signing: Requirements.
The Files and Folders prompts only show up if the process is running in a GUI login session. If not, the operation is allowed or denied based on existing information. If there’s no existing information, the operation is denied by default.
For more information about app and app group container protection, see the links in Trusted Execution Resources. For more information about app groups in general, see App Groups: macOS vs iOS: Fight!
On managed systems the site admin can use the com.apple.TCC.configuration-profile-policy payload to assign MAC privileges.
For testing purposes you can reset parts of TCC using the tccutil command-line tool. For general information about that tool, see its man page. For a list of TCC service names, see the posts on this thread.
Note TCC stands for transparency, consent, and control. It’s the subsystem within macOS that manages most of the privileges visible in System Settings > Privacy & Security. TCC has no API surface, but you see its name in various places, including the above-mentioned configuration profile payload and command-line tool, and the name of its accompanying daemon, tccd.
While tccutil is an easy way to do basic TCC testing, the most reliable way to test TCC is in a VM, restoring to a fresh snapshot between each test. If you want to try this out, crib ideas from Testing a Notarised Product.
The MAC privilege mechanism is heavily dependent on the concept of responsible code. For example, if an app contains a helper tool and the helper tool triggers a MAC prompt, we want:
The app’s name and usage description to appear in the alert.
The user’s decision to be recorded for the whole app, not that specific helper tool.
That decision to show up in System Settings under the app’s name.
For this to work the system must be able to tell that the app is the responsible code for the helper tool. The system has various heuristics to determine this and it works reasonably well in most cases. However, it’s possible to break this link. I haven’t fully research this but my experience is that this most often breaks when the child process does something ‘odd’ to break the link, such as trying to daemonise itself.
If you’re building a launchd daemon or agent and you find that it’s not correctly attributed to your app, add the AssociatedBundleIdentifiers property to your launchd property list. See the launchd.plist man page for the details.
Scripting
MAC presents some serious challenges for scripting because scripts are run by interpreters and the system can’t distinguish file system operations done by the interpreter from those done by the script. For example, if you have a script that needs to manipulate files on your desktop, you wouldn’t want to give the interpreter that privilege because then any script could do that.
The easiest solution to this problem is to package your script as a standalone program that MAC can use for its tracking. This may be easy or hard depending on the specific scripting environment. For example, AppleScript makes it easy to export a script as a signed app, but that’s not true for shell scripts.
TCC and Main Executables
TCC expects its bundled clients — apps, app extensions, and so on — to use a native main executable. That is, it expects the CFBundleExecutable property to be the name of a Mach-O executable. If your product uses a script as its main executable, you’re likely to encounter TCC problems. To resolve these, switch to using a Mach-O executable. For an example of how you might do that, see this post.
Revision History
2024-11-08 Added info about app group container protection. Clarified that Data Vaults are just one example of the techniques used internally by macOS. Made other editorial changes.
2023-06-13 Replaced two obsolete links with links to shiny new official documentation: Accessing files from the macOS App Sandbox and Discovering and diagnosing App Sandbox violations. Added a short discussion of app container protection and a link to WWDC 2023 Session 10053 What’s new in privacy.
2023-04-07 Added a link to my post about executable permissions. Fixed a broken link.
2023-02-10 In TCC and Main Executables, added a link to my native trampoline code. Introduced the concept of an implicit security scoped bookmark. Introduced AssociatedBundleIdentifiers. Made other minor editorial changes.
2022-04-26 Added an explanation of the TCC initialism. Added a link to Viewing Sandbox Violation Reports. Added the TCC and Main Executables section. Made significant editorial changes.
2022-01-10 Added a discussion of the file system hierarchy.
2021-04-26 First posted.
I'm trying to read the contents of a file on the filesystem in a macOS Swift app (Xcode 9 / Swift 4).I'm using the following snippet for it:let path = "/my/path/string.txt"
let s = try! String(contentsOfFile: path)
print(s)My problem is the following:1. This works in a Playground2. This works when I use the Command Line Tool macOS app template3. This terminates in a permission error when I use the Cocoa App macOS app templateThe permission error is the following:Fatal error: 'try!' expression unexpectedly raised an error:
Error Domain=NSCocoaErrorDomain Code=257 "The file "data.txt" couldn't be opened because you don't have permission to view it."
UserInfo={NSFilePath=/my/path/data.txt, NSUnderlyingError=0x60c0000449b0 {Error Domain=NSPOSIXErrorDomain Code=1 "Operation not permitted"}}I guess it's related to sandboxing but I found no information about it.1. How can I read from the filesystem in a sandboxed app? I mean there are so many GUI apps which need an Open File dialog, it cannot be a realistic restriction of sandboxed apps to not read files from outside the sandbox.2. Alternatively, how can I switch off sandboxing in Build Settings?3. Finally, I tried to compare the project.pbxproj files between the default Cocoa Apps and Command Line Tool template and I didn't see any meaningful difference, like something about security or sandbox. If not here, where are those settings stored?