Rosetta 2 Deadlock on M4 Pro
January 2026 Blizzard update causes a deadlock in Rosetta 2 on M4 chips. CodeWeavers (the developer of CrossOver) has analyzed the issue and identified it as a Rosetta translation failure, not a CrossOver application-level bug.
Hardware: M4 Pro Mac Book Pro
System: Tahoe 26.2
Impacted Software:
CrossOver 25.1.1
Diablo II: Resurrected
Delve into the world of built-in app and system services available to developers. Discuss leveraging these services to enhance your app's functionality and user experience.
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Hi,
I’m looking for clarification on what concurrency and consistency guarantees Apple provides when multiple targets (main app + Widget extensions) access shared storage.
Specifically:
1. UserDefaults (App Group / suiteName:)
• If multiple processes (app + multiple widget instances) read and write the same shared UserDefaults, what guarantees are provided?
• Is access serialized internally to prevent corruption?
• Are read–modify–write operations safe across processes, or can lost updates occur?
2. Core Data (shared SQLite store in App Group container)
• Is it officially supported for multiple processes to open and write to the same Core Data SQLite store?
• Are there recommended configurations (e.g. WAL mode) for safe multi-process access?
• Is Apple’s recommendation to have a single writer process?
3. FileManager (shared container files)
• If two processes write to the same file in an App Group container, what guarantees are provided by the system?
• Is atomic replaceItemAt the recommended pattern for safe cross-process updates?
Additionally:
• Do multiple widget instances count as separate processes with respect to these guarantees?
• Is there official guidance on best practices for shared persistence between app and widget extensions?
I want to ensure I’m following the correct architecture and not relying on undefined behavior.
Thanks.
Topic:
App & System Services
SubTopic:
Processes & Concurrency
Tags:
Foundation
WidgetKit
Core Data
Concurrency
Hi,
In my app, I have an option to remove a contact from a contact group (using the Contacts framework), and it's been working fine till recently users of the macOS version reported that it's not working. I have been using the CNSaveRequest removeMember(contact, from: group) API. The same API works fine on iOS. I'm not sure when it started but it seems to be affecting macOS14.6 as well as 15.1.
I was able to reproduce it in a small test project as well, and have the same experience (the API works on iOS but not on macOS), so it definitely seems like a problem with the framework. Can someone confirm this, and/or suggest a workaround?
Here's the code I run to test it out ...a simple SwiftUI view that has 4 buttons:
Create contact and group
Add contact to group
Remove contact from group
(optional) cleanup by deleting contact and group
It's the 3rd step that seems to fail on macOS, but works fine on iOS.
Here's the code to test it out:
struct ContentView: View {
let contactsModel = ContactsStoreModel()
var body: some View {
VStack (alignment: .center, spacing: 15){
Button ("1. Add Contact And Group") {
print("add contact button pressed")
contactsModel.addTestContact()
if let _ = contactsModel.createdContact {
print("created contact success")
}
}
Button ("2. Add Contact To Group") {
print("add to group button pressed")
contactsModel.addContactToGroup()
}
Button ("3. Remove Contact From Group") {
print("remove from group button pressed")
contactsModel.removeContactFromGroup()
}
Button ("4. Delete Contact and Group") {
print("remove from group button pressed")
contactsModel.deleteContactAndGroup()
}
}
.padding()
}
}
#Preview {
ContentView()
}
@available(iOS 13.0, *)
@objc final class ContactsStoreModel: NSObject, ObservableObject {
let contactStore = CNContactStore()
var createdContact : CNContact?
var createdGroup : CNGroup?
public func addTestContact() {
let storeContainer = contactStore.defaultContainerIdentifier()
let contact = CNMutableContact()
contact.givenName = "Testing"
contact.familyName = "User"
contact.phoneNumbers = [CNLabeledValue(label: "Cell", value: CNPhoneNumber(stringValue: "1234567890"))]
let group = CNMutableGroup()
group.name = "Testing Group"
print("create contact id = \(contact.identifier)")
print("create group id = \(group.identifier)")
do {
let saveRequest = CNSaveRequest()
saveRequest.transactionAuthor = "TestApp"
saveRequest.add(contact, toContainerWithIdentifier: storeContainer)
saveRequest.add(group, toContainerWithIdentifier: storeContainer)
try contactStore.execute(saveRequest)
createdContact = contact
createdGroup = group
} catch {
print("error in store execute = \(error)")
}
}
public func addContactToGroup() {
if let contact = createdContact, let group = createdGroup {
do {
let saveRequest = CNSaveRequest()
saveRequest.transactionAuthor = "TestApp"
saveRequest.addMember(contact, to: group)
try contactStore.execute(saveRequest)
}
catch {
print("error in store execute = \(error)")
}
}
}
public func removeContactFromGroup() {
if let contact = createdContact, let group = createdGroup {
do {
let saveRequest = CNSaveRequest()
saveRequest.transactionAuthor = "TestApp"
saveRequest.removeMember(contact, from: group)
try contactStore.execute(saveRequest)
}
catch {
print("error in store execute = \(error)")
}
}
}
public func addGroupAndContact() {
let storeContainer = contactStore.defaultContainerIdentifier()
let group = CNMutableGroup()
group.name = "Test Group"
print("create group id = \(group.identifier)")
if let contact = createdContact {
do {
let saveRequest = CNSaveRequest()
saveRequest.transactionAuthor = "TestApp"
saveRequest.add(group, toContainerWithIdentifier: storeContainer)
saveRequest.addMember(contact, to: group)
try contactStore.execute(saveRequest)
createdGroup = group
} catch {
print("error in store execute = \(error)")
}
}
}
public func deleteContactAndGroup() {
if let contact = createdContact, let group = createdGroup {
do {
let mutableGroup = group.mutableCopy() as! CNMutableGroup
let mutableContact = contact.mutableCopy() as! CNMutableContact
let saveRequest = CNSaveRequest()
saveRequest.transactionAuthor = "TestApp"
saveRequest.delete(mutableContact)
saveRequest.delete(mutableGroup)
try contactStore.execute(saveRequest)
}
catch {
print("error in deleting store execute = \(error)")
}
}
}
}
We are operating an application that uses WeatherKit.
Despite revoking a specific WeatherKit key on the Apple Developer website,
the number of API calls associated with that key continues to increase.
We are looking for a way to completely disable this particular key.
Any advice or suggestions would be greatly appreciated.
Several of my users are reporting on at lest recent and current versions of iOS the value from one characteristic can be swapped with another.
Originally I thought this was a library issue but it doesn't happen on Android and now a user with two iPhones using the exact same app and iOS 26.3 on both has the issue on one phone but not the other.
I've gone into more detail here which also includes a little data dumping to prove the values between characteristics can be mixed up.
https://github.com/dotintent/react-native-ble-plx/issues/1316
One user reported cycling Bluetooth on/off fixed the issue but the latest user says it does not.
For the peripheral the services can only change if the device enters firmware update mode (in which case the service UUID is different). Otherwise the characteristics on a service never change. This would make it a strange one to be caching related since the cache should always be correct.
在iOS 26.4 beta3版本中,当前支付完成,获取的票据是上次支付的票据,在拉起一笔支付成,获取的又是上次支付的票据
Topic:
App & System Services
SubTopic:
StoreKit
Our game application is developed based on StoreKit 1, and an exception occurs on iOS 26.4: after players complete a payment, the finishTransaction method fails to properly remove the transaction from the SKPaymentQueue; as a result, when players restart the app, the system still triggers the retry process for this transaction (reconciliation of unpaid orders).
Has anyone encountered this issue? If there is a solution, we would appreciate it if you could share it with us.
Topic:
App & System Services
SubTopic:
StoreKit
Hello, I am facing a validation error when uploading a macOS app with a Network Extension. The Error: Invalid system extension. The system extension at “[T] TEXT.app/Contents/Library/SystemExtensions/company_name.network-extension.systemextension” resides in an unexpected location. The Problem: Validation fails only when the app's Product Name contains square brackets: [T] TEXT. If I remove the brackets from the Product Name, validation passes. What I've tried: Setting Product Name to TEXT (without brackets) and CFBundleDisplayName to [T] TEXT. Cleaning Derived Data and rebuilding the archive. Verified that the extension is physically located at Contents/Library/SystemExtensions/. It seems the Apple validation tool fails to parse the bundle path correctly when it contains characters like [ or ]. Question: How can I keep the app name with brackets for the user (in System Settings and Menu Bar) while ensuring the Network Extension passes validation? Is there a way to escape these characters or a specific Info.plist configuration to satisfy the validator?"
Topic:
App & System Services
SubTopic:
General
Tags:
App Store Connect
Network Extension
System Extensions
<Apple Developer Program许可协议>已更新并需要查阅。若要更新现有App和提交新 App,账户持有人必须登录账户,查看并接受更新后的协议。
apple 会费到期 续费以后 无法获取app内购数据,经排查可能是这个协议没有签署,签署后多久可以重新获取到app内购数据。
Hello, I am facing a validation error when uploading a macOS app with a Network Extension. The Error: Invalid system extension. The system extension at “[T] TEXT.app/Contents/Library/SystemExtensions/company_name.network-extension.systemextension” resides in an unexpected location. The Problem: Validation fails only when the app's Product Name contains square brackets: [T] TEXT. If I remove the brackets from the Product Name, validation passes. What I've tried: Setting Product Name to TEXT (without brackets) and CFBundleDisplayName to [T] TEXT. Cleaning Derived Data and rebuilding the archive. Verified that the extension is physically located at Contents/Library/SystemExtensions/. It seems the Apple validation tool fails to parse the bundle path correctly when it contains characters like [ or ]. Question: How can I keep the app name with brackets for the user (in System Settings and Menu Bar) while ensuring the Network Extension passes validation? Is there a way to escape these characters or a specific Info.plist configuration to satisfy the validator?"
Topic:
App & System Services
SubTopic:
General
Tags:
App Store Connect
Network Extension
System Extensions
Hi,
I'm encountering a weird issue on iOS that happens:
for files with diacritics in their name, like "Gòmez.pdf" or "Télé.mp4",
when the iPhone or iPad main language is not set to English,
if the file has been created with a relatively low-level Unix function like fopen() or copyfile().
Then, the file cannot be previsualized using QuickLook or opened using other apps. Most of the time it fails silently, but on some occasions I get the following error message: "You do not have permission to save the file "filename.pdf" in the folder "myFolder"".
The issue is present in, at least, iOS 16 and 26. It seems worse in iOS 26. It seems that all three conditions are required, I don't see the issue when the iPhone or iPad is set to use English as the main language. I also don't see the issue if I rename the files in the Files app.
I'm probably doing something wrong, but what can it be?
(it's kind of weird that my recommendation for users becomes: if you want to use international characters in your file names, you need to set the iPad language to English...)
Topic:
App & System Services
SubTopic:
Core OS
Tags:
APFS
Internationalization
QuickLook
Files and Storage
What is screen studio: Screen studio is a screen recording app that lets users record screen and then edit the recording and add custom background image and it includes many apple wallpapers.
I seen this in tons of other apps as well
Topic:
App & System Services
SubTopic:
General
Hi there,
Starting with iOS 26.2 RC, all my DeviceActivityMonitor.eventDidReachThreshold get activated immediately as I pick up my iPhone for the first time, two nights in a row.
Feedback: FB21267341
There's always a chance something odd is happening to my device in particular (although I can't recall making any changes here and the debug logs point to the issue), but just getting this out there ASAP in case others are seeing this (or haven't tried!), and it's critical as this is the RC.
DeviceActivityMonitor.eventDidReachThreshold issues also mentioned here: https://developer.apple.com/forums/thread/793747; but I believe they are different and were potentially fixed in iOS 26.1, but it points to this part of the technology having issues and maybe someone from Apple has been tweaking it.
Topic:
App & System Services
SubTopic:
General
Tags:
Family Controls
Device Activity
Managed Settings
Screen Time
I'll try to ask a question that makes sense this time :) . I'm using the following method on NSFileManager:
(BOOL) getRelationship:(NSURLRelationship *) outRelationship
ofDirectoryAtURL:(NSURL *) directoryURL
toItemAtURL:(NSURL *) otherURL
error:(NSError * *) error;
Sets 'outRelationship' to NSURLRelationshipContains if the directory at 'directoryURL' directly or indirectly contains the item at 'otherURL', meaning 'directoryURL' is found while enumerating parent URLs starting from 'otherURL'. Sets 'outRelationship' to NSURLRelationshipSame if 'directoryURL' and 'otherURL' locate the same item, meaning they have the same NSURLFileResourceIdentifierKey value. If 'directoryURL' is not a directory, or does not contain 'otherURL' and they do not locate the same file, then sets 'outRelationship' to NSURLRelationshipOther. If an error occurs, returns NO and sets 'error'.
So this method falsely returns NSURLRelationshipSame for different directories. One is empty, one is not. Really weird behavior. Two file path urls pointing to two different file paths have the same NSURLFileResourceIdentifierKey? Could it be related to https://developer.apple.com/forums/thread/813641 ?
One url in the check lived at the same file path as the other url at one time (but no longer does). No symlinks or anything going on. Just plain directory urls.
And YES calling -removeCachedResourceValueForKey: with NSURLFileResourceIdentifierKey causes proper result of NSURLRelationshipOther to be returned. And I'm doing the check on a background queue.
We are getting vulnerabilities for passkit generator, used for apple wallet creation. Could you please suggest how to resolve this issue
In our system we updated MIME with latest version but passkit is referring older version 1.4.1
npm audit report
mime <1.4.1
Severity: high
mime Regular Expression Denial of Service when MIME lookup performed on untrusted user input - https://github.com/advisories/GHSA-wrvr-8mpx-r7pp
No fix available
node_modules/mime
passkit *
Depends on vulnerable versions of mime
node_modules/passkit
2 high severity vulnerabilities
Some issues need review, and may require choosing
a different dependency.
Topic:
App & System Services
SubTopic:
Wallet
We have a VPN app that uses NEPacketTunnelProvider with includeAllNetworks = true. We've encountered an issue where push notifications are not delivered over Wi-Fi while the tunnel is active in a pre-MFA quarantine state (tunnel is up but traffic is blocked on server side), regardless of whether excludeAPNS is set to true or false.
Observed behavior
Wi-Fi excludeAPNS = true - Notifications not delivered
Wi-Fi excludeAPNS = false - Notifications not delivered
Cellular excludeAPNS = true - Notifications delivered
Cellular excludeAPNS = false - Notifications not delivered
On cellular, the behavior matches our expectations: setting excludeAPNS = true allows APNS traffic to bypass the tunnel and notifications arrive; setting it to false routes APNS through the tunnel and notifications are blocked (as expected for a non-forwarding tunnel). On Wi-Fi, notifications fail to deliver in both cases.
Our question
Is this expected behavior when includeAllNetworks is enabled on Wi-Fi, or is this a known issue / bug with APNS delivery? Is there something else in the Wi-Fi networking path that includeAllNetworks affects beyond routing, which could prevent APNS from functioning even when the traffic is excluded from the tunnel?
Sample Project
Below is the minimal code that reproduces this issue. The project has two targets: a main app and a Network Extension. The tunnel provider captures all IPv4 and IPv6 traffic via default routes but does not forward packets — simulating a pre-MFA quarantine state. The main app configures the tunnel with includeAllNetworks = true and provides a UI toggle for excludeAPNS.
PacketTunnelProvider.swift (Network Extension target):
import NetworkExtension
class PacketTunnelProvider: NEPacketTunnelProvider {
override func startTunnel(options: [String : NSObject]?, completionHandler: @escaping (Error?) -> Void) {
let settings = NEPacketTunnelNetworkSettings(tunnelRemoteAddress: "127.0.0.1")
let ipv4 = NEIPv4Settings(addresses: ["198.51.100.1"], subnetMasks: ["255.255.255.0"])
ipv4.includedRoutes = [NEIPv4Route.default()]
settings.ipv4Settings = ipv4
let ipv6 = NEIPv6Settings(addresses: ["fd00::1"], networkPrefixLengths: [64])
ipv6.includedRoutes = [NEIPv6Route.default()]
settings.ipv6Settings = ipv6
let dns = NEDNSSettings(servers: ["198.51.100.1"])
settings.dnsSettings = dns
settings.mtu = 1400
setTunnelNetworkSettings(settings) { error in
if let error = error {
completionHandler(error)
return
}
self.readPackets()
completionHandler(nil)
}
}
private func readPackets() {
packetFlow.readPackets { [weak self] packets, protocols in
self?.readPackets()
}
}
override func stopTunnel(with reason: NEProviderStopReason, completionHandler: @escaping () -> Void) {
completionHandler()
}
override func handleAppMessage(_ messageData: Data, completionHandler: ((Data?) -> Void)?) {
if let handler = completionHandler {
handler(messageData)
}
}
override func sleep(completionHandler: @escaping () -> Void) {
completionHandler()
}
override func wake() {
}
}
ContentView.swift (Main app target) — trimmed to essentials:
import SwiftUI
import NetworkExtension
struct ContentView: View {
@State private var excludeAPNs = false
@State private var manager: NETunnelProviderManager?
var body: some View {
VStack {
Toggle("Exclude APNs", isOn: $excludeAPNs)
.onChange(of: excludeAPNs) { Task { await saveAndReload() } }
Button("Connect") { Task { await toggleVPN() } }
}
.padding()
.task { await loadManager() }
}
private func loadManager() async {
let managers = try? await NETunnelProviderManager.loadAllFromPreferences()
if let existing = managers?.first {
manager = existing
} else {
let m = NETunnelProviderManager()
let proto = NETunnelProviderProtocol()
proto.providerBundleIdentifier = "<your-extension-bundle-id>"
proto.serverAddress = "127.0.0.1"
proto.includeAllNetworks = true
proto.excludeAPNs = excludeAPNs
m.protocolConfiguration = proto
m.localizedDescription = "TestVPN"
m.isEnabled = true
try? await m.saveToPreferences()
try? await m.loadFromPreferences()
manager = m
}
if let proto = manager?.protocolConfiguration as? NETunnelProviderProtocol {
excludeAPNs = proto.excludeAPNs
}
}
private func saveAndReload() async {
guard let manager else { return }
if let proto = manager.protocolConfiguration as? NETunnelProviderProtocol {
proto.includeAllNetworks = true
proto.excludeAPNs = excludeAPNs
}
manager.isEnabled = true
try? await manager.saveToPreferences()
try? await manager.loadFromPreferences()
}
private func toggleVPN() async {
guard let manager else { return }
if manager.connection.status == .connected {
manager.connection.stopVPNTunnel()
} else {
await saveAndReload()
try? manager.connection.startVPNTunnel()
}
}
}
Steps to reproduce
Build and run the sample project with above code on a physical iOS device. Connect to a Wi-Fi network.
Set excludeAPNS = true using the toggle and tap Connect.
Send a push notification to the device to a test app with remote notification capability (e.g., via a test push service or the push notification console).
Observe that the notification is not delivered.
Disconnect. Switch to cellular. Reconnect with the same settings.
Send the same push notification — observe that it is delivered.
Environment
iOS 26.2
Xcode 26.2
Physical device (iPhone 15 Pro)
I'm trying to understand the terminology around forward vs backward references in CloudKit.
Say I have two record types:
User
LeaderboardScore (a score belongs to a user)
The score record stores a user reference:
score["user"] = CKRecord.Reference(
recordID: userRecordID,
action: .deleteSelf
)
So:
LeaderboardScore → User
The user record does not store any references to scores
From a data-model perspective:
Is this considered a forward reference (child → parent)?
Or a back reference, since the score is "pointing back" to its owner?
My use case is having leaderboard in my app and so i have created a user table to store all the users and a score table for saving the scores of each user of the app.
Hello,
We're seeing a high rate of providerDidReset callbacks in production across a large user base (iOS 16, 17, 18, and 26). I'd like to understand both the correct way to handle this delegate method and strategies to reduce its frequency.
Background
The callback occurs across all iOS versions we support and is not isolated to a specific device or region.
The callback can occur in any app state (foreground, background, inactive), however it is most dominant in the background state — particularly during VoIP push notification handling.
The callback is more prevalent during long app sessions — for example, when the app has been running continuously for a day or overnight.
We do not call CXProvider.invalidate() anywhere in our codebase explicitly.
After providerDidReset fires, subsequent transactions fail with CXErrorCodeRequestTransactionErrorUnknownCallUUID (error code 4).
Re-initializing the provider via initializeProvider() resolves this error.
Our Implementation
We use a singleton proxy class (CallKitProxy) that owns the CXProvider.
Below is a simplified version — some logging and non-essential parts have been removed for brevity.
@objcMembers
public final class CallKitProxy: NSObject {
private var cxProvider: CXProvider?
private let cxCallController: CXCallController
private let cxCallObserver: CXCallObserver
private override init() {
cxCallObserver = CXCallObserver()
cxCallController = CXCallController()
super.init()
initializeProvider()
cxCallObserver.setDelegate(self, queue: nil)
}
private func initializeProvider() {
let configuration = providerConfiguration()
cxProvider = CXProvider(configuration: configuration)
cxProvider?.setDelegate(self, queue: nil)
}
private func providerConfiguration() -> CXProviderConfiguration {
let soundName = SharedUDHelper.shared.string(forKey: .pushNotificationSoundNameForCall)
let sound = CallNotificationSounds(name: soundName ?? "ringtoneDefault")
let configuration = CXProviderConfiguration()
configuration.supportsVideo = true
configuration.maximumCallsPerCallGroup = 1
configuration.maximumCallGroups = 1
configuration.supportedHandleTypes = [.phoneNumber, .generic]
configuration.iconTemplateImageData = UIImage(
named: "callkit_mask",
in: .main,
compatibleWith: nil
)?.pngData()
configuration.ringtoneSound = sound.name
return configuration
}
public func requestTransaction(
action: CXCallAction,
completion: @escaping (Error?) -> Void
) {
let transaction = CXTransaction(action: action)
cxCallController.request(transaction) { error in
completion(error)
}
}
}
extension CallKitProxy: CXProviderDelegate {
public func providerDidReset(_ provider: CXProvider) {
// End any active calls, then re-initialize the provider
initializeProvider()
}
}
Questions
1. Is re-initializing the provider inside providerDidReset the correct approach?
The documentation states that providerDidReset signals the provider has been reset and all calls should be considered terminated. Should we be calling CXProvider.invalidate() on the old instance before creating a new one? Or is assigning a new CXProvider to cxProvider (which releases the old instance) sufficient?
2. What could be causing providerDidReset to fire so frequently, and how can we reduce it?
We're particularly concerned about cases triggered during VoIP push handling in the background and inactive states. Are there known conditions — such as provider configuration changes, app lifecycle events, or system memory pressure — that commonly trigger this callback? And are there any recommended patterns to make the provider more resilient in these scenarios?
Thank you.
In the WWDC 2019 session "Extended Runtime for WatchOS apps" the video talks about an entitlement being required to use the HR sensor judiciously in the background.
It provides a link to request the entitlement which no longer works: http://developer.apple.com/contect/request/health-monitoring
The session video is also quite hard to find these days.
Does anyone know why this is the case?
Is the API and entitlement still available?
Is there a supported way to run, even periodically, in the background on the Watch app (ignoring the background observer route which is known to be unreliable) and access existing HR sensor data
Topic:
App & System Services
SubTopic:
Health & Fitness
Tags:
WatchKit
Health and Fitness
watchOS
Apple Watch
I have this code in my Virutalization application
let process = Process()
process.executableURL = URL(fileURLWithPath: "/usr/sbin/diskutil")
process.arguments = ["image", "create", "blank",
"--fs", "none", "--format",
"ASIF", "--size", "2GiB",
url.path
]
try process.run()
process.waitUntilExit()
if process.terminationStatus == 0 {
print("✅ Disk image creation succeeded.")
} else {
print("❌ Disk image creation failed with exit code \(process.terminationStatus)")
}
} catch {
print("Process failed to launch: \(error.localizedDescription)")
return
}
this code was working fine until Tahoe 26.2. with the update of 26.3 the system freezes at process.waitUntilExit()
The code never exits and i get beech balls. This is working fine with intel macs. i am getting the problem in apple silicon m4 mac mini.
Any help would be appreciated.