Processes & Concurrency

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iOS feasibility question: user-initiated wake-word detection during active session
Hi all, Technical architecture question for those experienced with iOS background audio / microphone constraints. I’m exploring an app concept where: the user explicitly starts a temporary active session during that session, on-device wake-word / keyword detection runs locally no audio is stored or transmitted during passive monitoring monitoring stops when the user ends the session The intended UX is that the user may then lock the phone or place it away while the active session remains in progress. Question: Is there any App Store-compliant architecture that would allow local keyword / wake-word detection to continue while the device is locked or the app is backgrounded during that active session? Or would iOS lifecycle / background execution rules make this infeasible for custom wake-word detection? Interested in practical experience around: AVAudioSession background audio modes on-device speech processing App Review acceptability Thanks in advance.
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478
May ’26
Background Location Tracking Not Reliably Relaunching App After Termination
We are developing a mileage tracking application that depends on continuous background location updates on iOS. Our app has the required background modes enabled: <key>UIBackgroundModes</key> <array> <string>remote-notification</string> <string>processing</string> <string>fetch</string> <string>location</string> </array> We are observing inconsistent behavior with background location tracking in app terminated state. In some cases, after a period of time, location updates stop completely. Sometimes iOS successfully relaunches the app when movement is detected and location updates resume correctly. However, in other cases, the app is not relaunched by the system, and we stop receiving location updates entirely. We reviewed Apple’s documentation on handling background location updates: https://developer.apple.com/documentation/corelocation/handling-location-updates-in-the-background Based on our observations, we would appreciate clarification on the following points: Is this considered expected iOS behavior or a system limitation? Under what conditions does iOS decide not to relaunch a terminated app for location events? Are there recommended best practices to improve the reliability of background location relaunch behavior? Is there any logging, diagnostics, or debugging mechanism available to determine why the app was not relaunched? Apple’s documentation mentions that location updates may be queued while the app is terminated and later delivered after relaunch. However, in some scenarios we do not receive those queued updates after the app restarts. Under what conditions can queued location updates be discarded or not delivered? Additional notes: We are using standard Core Location background updates. “Always” location permission is granted. Background App Refresh is enabled. The issue is observed intermittently across multiple iOS devices.
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2w
Unable to enable login helper
I have one report from a customer, who migrated all data from his old MacBook to a new one. His is on Tahoe 26.5.1 (25F80). Here is my relevant code: + (BOOL)enableLoginItem:(BOOL)enable { NSOperatingSystemVersion osv = NSProcessInfo.processInfo.operatingSystemVersion; if (osv.majorVersion >= 13) { NSError* error; SMAppService* service = [SMAppService loginItemServiceWithIdentifier:MY_HELPER_APP_ID]; if (![service registerAndReturnError:&error] && error) @throw error; return YES; } return SMLoginItemSetEnabled((__bridge CFStringRef)MY_HELPER_APP_ID, enable); } What should I do to re-enable the login helper?
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5d
Is the Dock "Running in Background" indicator supposed to trigger for registered launchd jobs with no live process on macOS 27?
I just noticed something on macOS 27 beta 1 and I'm not sure if it's a bug or just how the new feature works. After quitting an app with Cmd+Q, the Dock keeps showing the gray dot with the "Running in Background" message. So I checked — ps aux shows nothing running for the app at all. The only trace is its auto-updater job in launchctl list (com.anthropic.claudefordesktop.ShipIt), which is registered but has no PID, so it's not actually executing anything. Out of curiosity I tried Discord and got the exact same thing (com.discord.discord.ShipIt), so this probably happens with any Electron app that uses the Squirrel updater. Is this intended behavior? Trying to understand if the indicator reflects registered background items (and not just live processes) so I know what to expect for Electron-based apps.
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90
1w
Maximum number of BGContinuedProcessingTasks?
I have a weird situation arising in my app where calling BGTaskScheduler.shared.submit(request) seems to fail silently, without raising any of the BGTaskScheduler.Error's. Here's what's happening. A user registers and submits 5 BGContinuedProcessingTask's, with different ID's using the wildcard. When trying to submit the 6th task like this: try bgTask.submit() //submit task isCreatingBGTask = false // toggle ProgressView off dismiss() //Dismiss the sheet The sheet will dismiss, but the device never gives the haptic feedback, and the task is not visible in the notification centre. Having a maximum number of running tasks makes sense, but why isn't it raising the error BGTaskScheduler.Error(.immediateRunIneligible). It also doesn't seem like there's a way to query the tasks that are in progress (at least I couldn't find a way). So for now I'll just track my own tasks manually, and prevent submission at 5 tasks, but I'm wondering what would happen if another app had 2 tasks going, and then my user tries to submit 3 or something like that.
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4d
app background launch unexpectedly
Our app will launch automatically in the background,Doubt is the result of background fetch ,so we cancel the background modes setting of the background fetch,but we still can see the performFetchWithCompletionHandler method called when app launch in the background。Background launch will cause some bugs in our app. We don't want the app to start in the background. We hope to get help
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915
Dec ’25
Called endBackgroundTask but not working
When my app enter to background, I start a background task, and when Expiration happens, I end my background task. The code likes below: backgroundTask = [[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:^{ dispatch_async(dispatch_get_main_queue(), ^{ if (backgroundTask != UIBackgroundTaskInvalid) { [[UIApplication sharedApplication] endBackgroundTask:backgroundTask]; backgroundTask = UIBackgroundTaskInvalid; [self cancel]; } }); }]; When the breakpoint is triggered at the endBackgroundTask line, I also get the following log: [BackgroundTask] Background task still not ended after expiration handlers were called: <UIBackgroundTaskInfo: 0x282d7ab40>: taskID = 36, taskName = Called by MyApp, from MyMethod, creationTime = 892832 (elapsed = 26). This app will likely be terminated by the system. Call UIApplication.endBackgroundTask(:) to avoid this. The log don't appear every time, so why is that? Is there something wrong with my code?
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3.2k
Jun ’25
Sensorkit - Troubleshooting SRErrorDataInaccessible in Background Fetch with SensorKit
Hello, I am currently developing an iOS application using SensorKit. I encountered an issue when attempting to fetch SensorKit data in the background using background tasks (appRefresh, processing). The following error occurs: In the delegate function func sensorReader(_ reader: SRSensorReader, fetching fetchRequest: SRFetchRequest, failedWithError error: any Error) {}, I receive the error: SRErrorDataInaccessible. In code specific manner: start and handle background fetch (appRefresh) func handleAppRefreshTask(task: BGAppRefreshTask) { logger.logWithServer(level: .default, message: "background fetch start", category: String(describing: BackgroundTaskManager.self)) scheduleBackgroundFetch() let queue = OperationQueue() queue.maxConcurrentOperationCount = 1 let fetchOperation = FetchOperation() queue.addOperation(fetchOperation) task.expirationHandler = { self.logger.logWithServer(level: .error, message: "background fetch expirated", category: String(describing: BackgroundTaskManager.self)) queue.cancelAllOperations() } fetchOperation.completionBlock = { task.setTaskCompleted(success: !fetchOperation.isCancelled) } } Background fetch operation class class FetchOperation: Operation { override func main() { guard !isCancelled else { return } Task { // this function will execute fetch request for all user allowed sensorReader, 'func fetch(_ request: SRFetchRequest)' await SensorkitManager.shared.startFetchAndUpload() } } } I have the following questions: Is it possible to fetch SensorKit data in the background? If it is possible, why does the above error occur? If it is possible, could you provide the solution code and the correct workflow to avoid this error? Thank you.
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1.4k
Feb ’26
How to correctly deploy bundled launchdaemons/launchagents?
I'm working on an enterprise product that's mainly a daemon (with Endpoint Security) without any GUI component. I'm looking into the update process for daemons/agents that was introduced with Ventura (Link), but I have to say that the entire process is just deeply unfun. Really can't stress this enough how unfun. Anyway... The product bundle now contains a dedicated Swift executable that calls SMAppService.register for both the daemon and agent. It registers the app in the system preferences login items menu, but I also get an error. Error registering daemon: Error Domain=SMAppServiceErrorDomain Code=1 "Operation not permitted" UserInfo={NSLocalizedFailureReason=Operation not permitted} What could be the reason? I wouldn't need to activate the items, I just need them to be added to the list, so that I can control them via launchctl. Which leads me to my next question, how can I control bundled daemons/agents via launchctl? I tried to use launchctl enable and bootstrap, just like I do with daemons under /Library/LaunchDaemons, but all I get is sudo launchctl enable system/com.identifier.daemon sudo launchctl bootstrap /Path/to/daemon/launchdplist/inside/bundle/Library/LaunchDaemons/com.blub.plist Bootstrap failed: 5: Input/output error (not super helpful error message) I'm really frustrated by the complexity of this process and all of its pitfalls.
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1.3k
Aug ’25
macOS 14 XPC vs Foundation XPC
I'm looking into a newer XPC API available starting with macOS 14. Although it's declared as a low-level API I can't figure it how to specify code signing requirement using XPCListener and XPCSession. How do I connect it with xpc_listener_set_peer_code_signing_requirement and xpc_connection_set_peer_code_signing_requirement which require xpc_listener_t and xpc_connection_t respectively? Foundation XPC is declared as a high-level API and provides easy ways to specify code signing requirements on both ends of xpc. I'm confused with all these XPC APIs and their future: Newer really high-level XPCListener and XPCSession API (in low-level framework???) Low-level xpc_listener_t & xpc_connection_t -like API. Is it being replaced by newer XPCListener and XPCSession? How is it related to High-level Foundation XPC? Are NSXPCListener and NSXPCConnection going to be deprecated and replaced by XPCListener and XPCSession??
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Aug ’25
Some fundamental doubts about DisptachQueue and GCD
I understand that GCD and it's underlying implementations have evolved over time. And many things have not been shared explicitly in Apple documentation. The most concepts of DispatchQueue (serial and concurrent queues), DispatchQoS, target queue and system provided queues: main and globals etc. I have some doubts & questions to clarify: [Main Dispatch Queue] [Link] Because the main queue doesn't behave entirely like a regular serial queue, it may have unwanted side-effects when used in processes that are not UI apps (daemons). For such processes, the main queue should be avoided. What does it mean? Can you elaborate? [Global Concurrent Dispatch Queues] Are they global to a process or across processes on a device. I believe it is the first case but just wanted to be sure. [Global Concurrent Dispatch Queues] Does system create 4 (for each QoS) * 2 (over-commiting and non-overcommiting queues) = 8 queues in all. When does which type of queue comes into play? [Custom Queue][Target Queue concept] [swift-corelibs-libdispatch/man/dispatch_queue_create.3] QUOTE The default target queue of all dispatch objects created by the application is the default priority global concurrent queue. UNQUOTE Is this stil true? We could not find a mention of this in any latest official apple documentation (though some old forum threads (one more) and github code documentation indicate the same). The official documentation only says: [dispatch_set_target_queue] QUOTE If you want the system to provide a queue that is appropriate for the current object UNQUOTE [dispatch_queue_create_with_target] QUOTE Specify DISPATCH_TARGET_QUEUE_DEFAULT to set the target queue to the default type for the current dispatch queue.UNQUOTE [Dispatch>DispatchQueue>init] QUOTE Specify DISPATCH_TARGET_QUEUE_DEFAULT if you want the system to provide a queue that is appropriate for the current object. UNQUOTE What is the difference between passing target queue as 'nil' vs 'DISPATCH_TARGET_QUEUE_DEFAULT' to DispatchQueue init? [Custom Queue][Target Queue concept] [dispatch_set_target_queue] QUOTE The system doesn't allocate threads to the dispatch queue if it has a target queue, unless that target queue is a global concurrent queue. UNQUOTE The system does allocate threads to the custom dispatch queues that have global concurrent queue as the default target. What does that mean? Why does targetting to global concurrent queues mean in that case? [System / GCD Thread Pool] that excutes work items from DispatchQueue: Is this thread pool per queue? or across queues per process? or across processes per device?
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1.6k
Jan ’26
What DispatchQueues should i use for my app's communication subsystem?
We would be creating N NWListener objects and M NWConnection objects in our process' communication subsystem to create server sockets, accepted client sockets on server and client sockets on clients. Both NWConnection and NWListener rely on DispatchQueue to deliver state changes, incoming connections, send/recv completions etc. What DispatchQueues should I use and why? Global Concurrent Dispatch Queue (and which QoS?) for all NWConnection and NWListener One custom concurrent queue (which QoS?) for all NWConnection and NWListener? (Does that anyways get targetted to one of the global queues?) One custom concurrent queue per NWConnection and NWListener though all targetted to Global Concurrent Dispatch Queue (and which QoS?)? One custom concurrent queue per NWConnection and NWListener though all targetted to single target custom concurrent queue? For every option above, how am I impacted in terms of parallelism, concurrency, throughput &amp; latency and how is overall system impacted (with other processes also running)? Seperate questions (sorry for the digression): Are global concurrent queues specific to a process or shared across all processes on a device? Can I safely use setSpecific on global dispatch queues in our app?
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1.4k
Jan ’26
Background Audio Recording
I have an app that uses background audio recording. From what others say, I have enabled the audio background mode to keep the audio session active, and this worked. But when submitting the app to the app store, the app was rejected because the audio background mode is only supposed to be used for audio playback. How do I create this background mode while following Apple's guidelines?
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430
Jan ’26
Background App Refresh
Hi, I have a couple questions about background app refresh. First, is the function RefreshAppContentsOperation() where to implement code that needs to be run in the background? Second, despite importing BackgroundTasks, I am getting the error "cannot find operationQueue in scope". What can I do to resolve that? Thank you. func scheduleAppRefresh() { let request = BGAppRefreshTaskRequest(identifier: "peaceofmindmentalhealth.RoutineRefresh") // Fetch no earlier than 15 minutes from now. request.earliestBeginDate = Date(timeIntervalSinceNow: 15 * 60) do { try BGTaskScheduler.shared.submit(request) } catch { print("Could not schedule app refresh: \(error)") } } func handleAppRefresh(task: BGAppRefreshTask) { // Schedule a new refresh task. scheduleAppRefresh() // Create an operation that performs the main part of the background task. let operation = RefreshAppContentsOperation() // Provide the background task with an expiration handler that cancels the operation. task.expirationHandler = { operation.cancel() } // Inform the system that the background task is complete // when the operation completes. operation.completionBlock = { task.setTaskCompleted(success: !operation.isCancelled) } // Start the operation. operationQueue.addOperation(operation) } func RefreshAppContentsOperation() -> Operation { }
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1.2k
Jan ’26
Incorrect behaviour of task_info() syscall after an unrelated dlclose() call
For some reason, after invoking an unrelated dlclose() call to unload any .dylib that had previously been loaded via dlopen(..., RTLD_NOW), the subsequent call to task_info(mach_task_self(), TASK_DYLD_INFO, ...) syscall returns unexpected structure in dyld_uuid_info image_infos-&gt;uuidArray, that, while it seems to represent an array of struct dyld_uuid_info elements, there is only 1 such element (dyld_all_image_infos *infos-&gt;uuidArrayCount == 1) and the app crashes when trying to access dyld_uuid_info image-&gt;imageLoadAddress-&gt;magic, as image-&gt;imageLoadAddress doesn't seem to represent a valid struct mach_header structure address (although it looks like a normal pointer within the process address space. What does it point to?). This reproduces on macOS 15.4.1 (24E263) Could you please confirm that this is a bug in the specified OS build, or point to incorrect usage of the task_info() API? Attaching the C++ file that reproduces the issue to this email message It needs to be built on macOS 15.4.1 (24E263) via Xcode or just a command line clang++ compiler. It may crash or return garbage, depending on memory layout, but on this macOS build it doesn’t return a correct feedfacf magic number for the struct mach_header structure. Thank you Feedback Assistant reference: FB18431345 //On `macOS 15.4.1 (24E263)` create a C++ application (for example, in Xcode), with the following contents. Note, that this application should crash on this macOS build. It will not crash, however, if you either: //1. Comment out `dlclose()` call //2. Change the order of the `performDlOpenDlClose()` and `performTaskInfoSyscall()` functions calls (first performTaskInfoSyscall() then performDlOpenDlClose()). #include &lt;iostream&gt; #include &lt;dlfcn.h&gt; #include &lt;mach/mach.h&gt; #include &lt;mach-o/dyld_images.h&gt; #include &lt;mach-o/loader.h&gt; void performDlOpenDlClose() { printf("dlopen/dlclose function\n"); printf("Note: please adjust the path below to any real dylib on your system, if the path below doesn't exist!\n"); std::string path = "/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/libswiftDemangle.dylib"; printf("Dylib to open: %s\n", path.c_str()); void* handle = ::dlopen(path.c_str(), RTLD_NOW); if(handle) { ::dlclose(handle); } else { printf("Error: %s\n", dlerror()); } } void performTaskInfoSyscall() { printf("Making a task_info() syscall\n"); printf("\033[34mSource File: %s\033[0m\n", __FILE__); task_t task = mach_task_self(); struct task_dyld_info dyld_info; mach_msg_type_number_t size = TASK_DYLD_INFO_COUNT; kern_return_t kr = task_info(task, TASK_DYLD_INFO, (task_info_t)&amp;dyld_info, &amp;size); if (kr != KERN_SUCCESS) { fprintf(stderr, "task_info failed: %s\n", mach_error_string(kr)); } const struct dyld_all_image_infos* infos = (const struct dyld_all_image_infos*)dyld_info.all_image_info_addr; printf("version: %d, infos-&gt;infoArrayCount: %d\n", infos-&gt;version, infos-&gt;infoArrayCount); for(uint32_t i=0; i&lt;infos-&gt;infoArrayCount; i++) { dyld_image_info image = infos-&gt;infoArray[i]; const struct mach_header* header = image.imageLoadAddress; printf("%d ", i); printf("%p ", (void*)image.imageLoadAddress); printf("(%x) ", header-&gt;magic); printf("%s\n", image.imageFilePath); fflush(stdout); } printf("\n\n"); printf("infos-&gt;uuidArrayCount: %lu\n", infos-&gt;uuidArrayCount); for(uint32_t i=0; i&lt;infos-&gt;uuidArrayCount; i++) { dyld_uuid_info image = infos-&gt;uuidArray[i]; const struct mach_header* header = image.imageLoadAddress; printf("%d ", i); printf("%p ", (void*)image.imageLoadAddress); printf("(%x)\n", header-&gt;magic); fflush(stdout); } printf("task_info() syscall result processing is completed\n\n"); } int main(int argc, const char * argv[]) { performDlOpenDlClose(); performTaskInfoSyscall(); return 0; }
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200
Jun ’25
utmpx reports several session for the same user
Hello, My app (daemon) time to time need to know list of GUI login sessions. According to the recommendation, I am using getutxent(). https://developer.apple.com/library/archive/qa/qa1133/_index.html However, I have faced with unclear behaviour in case of running "Migration Assistant". It can be re-created without my app. Steps to recreate: login as 'user #1' start "Migration Assistant" quit "Migration Assistant" new login prompt will be opened login as 'user #2' In spite the session of 'user #1' is closed, the command line tool "who", which gathers information from /var/run/utmpx, reports opened sessions of 'user #1'. Is it bug or feature? Thank you in advance!
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314
Jul ’25
DispatchSerialQueue minimum OS support
Hi Team, We intend to create a custom serial dispatch queue targetting a global queue. let serialQueue = DispatchQueue(label: "corecomm.tallyworld.serial", target: DispatchQueue.global(qos: .default)) The documentation for DispatchQueue init does not show any minimum OS versions. BUT DispatchSerialQueue init does show iOS 17.0+ iPadOS 17.0+ Mac Catalyst macOS 14.0+ tvOS 17.0+ visionOS watchOS 10.0+. Does that mean - I will not be able to create a custom serial dispatch queue below iOS 17?
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391
Jul ’25
iOS Team Provisioning Profile” Missing UIBackgroundModes Entitlement
I’m trying to enable Background Modes (specifically for audio, background fetch, remote notifications) in my iOS SwiftUI app, but I’m getting this error: Provisioning profile “iOS Team Provisioning Profile: [my app]” doesn’t include the UIBackgroundModes entitlement. On the developer website when I make the provision profile It doesnt give me the option to allow background modes. I added it to the sign in capabilities seccion in X code and matched the bundle ID to the provision profile and certificate etc but it still runs this error because the provision profile doesnt have the entitlements..
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374
Jul ’25
ExtensionKit & ExtensionFoundation process lifecycle
An XPC service’s process has a system-managed lifecycle: the process is launched on-demand when another process tries to connect to it, and the system can decide to kill it when system resources are low. XPC services can tell the system when they shouldn’t be killed using xpc_transaction_begin/end. Do extensions created with ExtensionFoundation and/or ExtensionKit have the same behavior?
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294
Jul ’25
Need to start the Mac application automatically
I am developing the application in Mac. My requirement is to start the application automatically when user login. I have tried adding the plist file in launch agents, But it doesn't achieve my requirement. Please find the code added in the launch agents &lt;?xml version="1.0" encoding="UTF-8"?&gt; &lt;!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"&gt; &lt;plist version="1.0"&gt; &lt;dict&gt; &lt;key&gt;Label&lt;/key&gt; &lt;string&gt;com.sftk.secure&lt;/string&gt; &lt;key&gt;ProgramArguments&lt;/key&gt; &lt;array&gt; &lt;string&gt;/Applications/Testing.app/Contents/MacOS/Testing&lt;/string&gt; &lt;/array&gt; &lt;key&gt;RunAtLoad&lt;/key&gt; &lt;true/&gt; &lt;key&gt;KeepAlive&lt;/key&gt; &lt;false/&gt; &lt;/dict&gt; &lt;/plist&gt; I have tried by adding manually in the setting, but it was opened sometimes and closed suddenly. On open manually it works. Please provide a solution to start the application automatically on system starts
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2.1k
Jul ’25
iOS feasibility question: user-initiated wake-word detection during active session
Hi all, Technical architecture question for those experienced with iOS background audio / microphone constraints. I’m exploring an app concept where: the user explicitly starts a temporary active session during that session, on-device wake-word / keyword detection runs locally no audio is stored or transmitted during passive monitoring monitoring stops when the user ends the session The intended UX is that the user may then lock the phone or place it away while the active session remains in progress. Question: Is there any App Store-compliant architecture that would allow local keyword / wake-word detection to continue while the device is locked or the app is backgrounded during that active session? Or would iOS lifecycle / background execution rules make this infeasible for custom wake-word detection? Interested in practical experience around: AVAudioSession background audio modes on-device speech processing App Review acceptability Thanks in advance.
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478
Activity
May ’26
Background Location Tracking Not Reliably Relaunching App After Termination
We are developing a mileage tracking application that depends on continuous background location updates on iOS. Our app has the required background modes enabled: <key>UIBackgroundModes</key> <array> <string>remote-notification</string> <string>processing</string> <string>fetch</string> <string>location</string> </array> We are observing inconsistent behavior with background location tracking in app terminated state. In some cases, after a period of time, location updates stop completely. Sometimes iOS successfully relaunches the app when movement is detected and location updates resume correctly. However, in other cases, the app is not relaunched by the system, and we stop receiving location updates entirely. We reviewed Apple’s documentation on handling background location updates: https://developer.apple.com/documentation/corelocation/handling-location-updates-in-the-background Based on our observations, we would appreciate clarification on the following points: Is this considered expected iOS behavior or a system limitation? Under what conditions does iOS decide not to relaunch a terminated app for location events? Are there recommended best practices to improve the reliability of background location relaunch behavior? Is there any logging, diagnostics, or debugging mechanism available to determine why the app was not relaunched? Apple’s documentation mentions that location updates may be queued while the app is terminated and later delivered after relaunch. However, in some scenarios we do not receive those queued updates after the app restarts. Under what conditions can queued location updates be discarded or not delivered? Additional notes: We are using standard Core Location background updates. “Always” location permission is granted. Background App Refresh is enabled. The issue is observed intermittently across multiple iOS devices.
Replies
4
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0
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507
Activity
2w
Unable to enable login helper
I have one report from a customer, who migrated all data from his old MacBook to a new one. His is on Tahoe 26.5.1 (25F80). Here is my relevant code: + (BOOL)enableLoginItem:(BOOL)enable { NSOperatingSystemVersion osv = NSProcessInfo.processInfo.operatingSystemVersion; if (osv.majorVersion >= 13) { NSError* error; SMAppService* service = [SMAppService loginItemServiceWithIdentifier:MY_HELPER_APP_ID]; if (![service registerAndReturnError:&error] && error) @throw error; return YES; } return SMLoginItemSetEnabled((__bridge CFStringRef)MY_HELPER_APP_ID, enable); } What should I do to re-enable the login helper?
Replies
2
Boosts
0
Views
130
Activity
5d
Is the Dock "Running in Background" indicator supposed to trigger for registered launchd jobs with no live process on macOS 27?
I just noticed something on macOS 27 beta 1 and I'm not sure if it's a bug or just how the new feature works. After quitting an app with Cmd+Q, the Dock keeps showing the gray dot with the "Running in Background" message. So I checked — ps aux shows nothing running for the app at all. The only trace is its auto-updater job in launchctl list (com.anthropic.claudefordesktop.ShipIt), which is registered but has no PID, so it's not actually executing anything. Out of curiosity I tried Discord and got the exact same thing (com.discord.discord.ShipIt), so this probably happens with any Electron app that uses the Squirrel updater. Is this intended behavior? Trying to understand if the indicator reflects registered background items (and not just live processes) so I know what to expect for Electron-based apps.
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0
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0
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90
Activity
1w
Maximum number of BGContinuedProcessingTasks?
I have a weird situation arising in my app where calling BGTaskScheduler.shared.submit(request) seems to fail silently, without raising any of the BGTaskScheduler.Error's. Here's what's happening. A user registers and submits 5 BGContinuedProcessingTask's, with different ID's using the wildcard. When trying to submit the 6th task like this: try bgTask.submit() //submit task isCreatingBGTask = false // toggle ProgressView off dismiss() //Dismiss the sheet The sheet will dismiss, but the device never gives the haptic feedback, and the task is not visible in the notification centre. Having a maximum number of running tasks makes sense, but why isn't it raising the error BGTaskScheduler.Error(.immediateRunIneligible). It also doesn't seem like there's a way to query the tasks that are in progress (at least I couldn't find a way). So for now I'll just track my own tasks manually, and prevent submission at 5 tasks, but I'm wondering what would happen if another app had 2 tasks going, and then my user tries to submit 3 or something like that.
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0
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0
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43
Activity
4d
app background launch unexpectedly
Our app will launch automatically in the background,Doubt is the result of background fetch ,so we cancel the background modes setting of the background fetch,but we still can see the performFetchWithCompletionHandler method called when app launch in the background。Background launch will cause some bugs in our app. We don't want the app to start in the background. We hope to get help
Replies
4
Boosts
0
Views
915
Activity
Dec ’25
Called endBackgroundTask but not working
When my app enter to background, I start a background task, and when Expiration happens, I end my background task. The code likes below: backgroundTask = [[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:^{ dispatch_async(dispatch_get_main_queue(), ^{ if (backgroundTask != UIBackgroundTaskInvalid) { [[UIApplication sharedApplication] endBackgroundTask:backgroundTask]; backgroundTask = UIBackgroundTaskInvalid; [self cancel]; } }); }]; When the breakpoint is triggered at the endBackgroundTask line, I also get the following log: [BackgroundTask] Background task still not ended after expiration handlers were called: <UIBackgroundTaskInfo: 0x282d7ab40>: taskID = 36, taskName = Called by MyApp, from MyMethod, creationTime = 892832 (elapsed = 26). This app will likely be terminated by the system. Call UIApplication.endBackgroundTask(:) to avoid this. The log don't appear every time, so why is that? Is there something wrong with my code?
Replies
3
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0
Views
3.2k
Activity
Jun ’25
Sensorkit - Troubleshooting SRErrorDataInaccessible in Background Fetch with SensorKit
Hello, I am currently developing an iOS application using SensorKit. I encountered an issue when attempting to fetch SensorKit data in the background using background tasks (appRefresh, processing). The following error occurs: In the delegate function func sensorReader(_ reader: SRSensorReader, fetching fetchRequest: SRFetchRequest, failedWithError error: any Error) {}, I receive the error: SRErrorDataInaccessible. In code specific manner: start and handle background fetch (appRefresh) func handleAppRefreshTask(task: BGAppRefreshTask) { logger.logWithServer(level: .default, message: "background fetch start", category: String(describing: BackgroundTaskManager.self)) scheduleBackgroundFetch() let queue = OperationQueue() queue.maxConcurrentOperationCount = 1 let fetchOperation = FetchOperation() queue.addOperation(fetchOperation) task.expirationHandler = { self.logger.logWithServer(level: .error, message: "background fetch expirated", category: String(describing: BackgroundTaskManager.self)) queue.cancelAllOperations() } fetchOperation.completionBlock = { task.setTaskCompleted(success: !fetchOperation.isCancelled) } } Background fetch operation class class FetchOperation: Operation { override func main() { guard !isCancelled else { return } Task { // this function will execute fetch request for all user allowed sensorReader, 'func fetch(_ request: SRFetchRequest)' await SensorkitManager.shared.startFetchAndUpload() } } } I have the following questions: Is it possible to fetch SensorKit data in the background? If it is possible, why does the above error occur? If it is possible, could you provide the solution code and the correct workflow to avoid this error? Thank you.
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Feb ’26
How to correctly deploy bundled launchdaemons/launchagents?
I'm working on an enterprise product that's mainly a daemon (with Endpoint Security) without any GUI component. I'm looking into the update process for daemons/agents that was introduced with Ventura (Link), but I have to say that the entire process is just deeply unfun. Really can't stress this enough how unfun. Anyway... The product bundle now contains a dedicated Swift executable that calls SMAppService.register for both the daemon and agent. It registers the app in the system preferences login items menu, but I also get an error. Error registering daemon: Error Domain=SMAppServiceErrorDomain Code=1 "Operation not permitted" UserInfo={NSLocalizedFailureReason=Operation not permitted} What could be the reason? I wouldn't need to activate the items, I just need them to be added to the list, so that I can control them via launchctl. Which leads me to my next question, how can I control bundled daemons/agents via launchctl? I tried to use launchctl enable and bootstrap, just like I do with daemons under /Library/LaunchDaemons, but all I get is sudo launchctl enable system/com.identifier.daemon sudo launchctl bootstrap /Path/to/daemon/launchdplist/inside/bundle/Library/LaunchDaemons/com.blub.plist Bootstrap failed: 5: Input/output error (not super helpful error message) I'm really frustrated by the complexity of this process and all of its pitfalls.
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7
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1.3k
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Aug ’25
macOS 14 XPC vs Foundation XPC
I'm looking into a newer XPC API available starting with macOS 14. Although it's declared as a low-level API I can't figure it how to specify code signing requirement using XPCListener and XPCSession. How do I connect it with xpc_listener_set_peer_code_signing_requirement and xpc_connection_set_peer_code_signing_requirement which require xpc_listener_t and xpc_connection_t respectively? Foundation XPC is declared as a high-level API and provides easy ways to specify code signing requirements on both ends of xpc. I'm confused with all these XPC APIs and their future: Newer really high-level XPCListener and XPCSession API (in low-level framework???) Low-level xpc_listener_t & xpc_connection_t -like API. Is it being replaced by newer XPCListener and XPCSession? How is it related to High-level Foundation XPC? Are NSXPCListener and NSXPCConnection going to be deprecated and replaced by XPCListener and XPCSession??
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949
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Aug ’25
Some fundamental doubts about DisptachQueue and GCD
I understand that GCD and it's underlying implementations have evolved over time. And many things have not been shared explicitly in Apple documentation. The most concepts of DispatchQueue (serial and concurrent queues), DispatchQoS, target queue and system provided queues: main and globals etc. I have some doubts & questions to clarify: [Main Dispatch Queue] [Link] Because the main queue doesn't behave entirely like a regular serial queue, it may have unwanted side-effects when used in processes that are not UI apps (daemons). For such processes, the main queue should be avoided. What does it mean? Can you elaborate? [Global Concurrent Dispatch Queues] Are they global to a process or across processes on a device. I believe it is the first case but just wanted to be sure. [Global Concurrent Dispatch Queues] Does system create 4 (for each QoS) * 2 (over-commiting and non-overcommiting queues) = 8 queues in all. When does which type of queue comes into play? [Custom Queue][Target Queue concept] [swift-corelibs-libdispatch/man/dispatch_queue_create.3] QUOTE The default target queue of all dispatch objects created by the application is the default priority global concurrent queue. UNQUOTE Is this stil true? We could not find a mention of this in any latest official apple documentation (though some old forum threads (one more) and github code documentation indicate the same). The official documentation only says: [dispatch_set_target_queue] QUOTE If you want the system to provide a queue that is appropriate for the current object UNQUOTE [dispatch_queue_create_with_target] QUOTE Specify DISPATCH_TARGET_QUEUE_DEFAULT to set the target queue to the default type for the current dispatch queue.UNQUOTE [Dispatch>DispatchQueue>init] QUOTE Specify DISPATCH_TARGET_QUEUE_DEFAULT if you want the system to provide a queue that is appropriate for the current object. UNQUOTE What is the difference between passing target queue as 'nil' vs 'DISPATCH_TARGET_QUEUE_DEFAULT' to DispatchQueue init? [Custom Queue][Target Queue concept] [dispatch_set_target_queue] QUOTE The system doesn't allocate threads to the dispatch queue if it has a target queue, unless that target queue is a global concurrent queue. UNQUOTE The system does allocate threads to the custom dispatch queues that have global concurrent queue as the default target. What does that mean? Why does targetting to global concurrent queues mean in that case? [System / GCD Thread Pool] that excutes work items from DispatchQueue: Is this thread pool per queue? or across queues per process? or across processes per device?
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1.6k
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Jan ’26
What DispatchQueues should i use for my app's communication subsystem?
We would be creating N NWListener objects and M NWConnection objects in our process' communication subsystem to create server sockets, accepted client sockets on server and client sockets on clients. Both NWConnection and NWListener rely on DispatchQueue to deliver state changes, incoming connections, send/recv completions etc. What DispatchQueues should I use and why? Global Concurrent Dispatch Queue (and which QoS?) for all NWConnection and NWListener One custom concurrent queue (which QoS?) for all NWConnection and NWListener? (Does that anyways get targetted to one of the global queues?) One custom concurrent queue per NWConnection and NWListener though all targetted to Global Concurrent Dispatch Queue (and which QoS?)? One custom concurrent queue per NWConnection and NWListener though all targetted to single target custom concurrent queue? For every option above, how am I impacted in terms of parallelism, concurrency, throughput &amp; latency and how is overall system impacted (with other processes also running)? Seperate questions (sorry for the digression): Are global concurrent queues specific to a process or shared across all processes on a device? Can I safely use setSpecific on global dispatch queues in our app?
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13
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1.4k
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Jan ’26
Background Audio Recording
I have an app that uses background audio recording. From what others say, I have enabled the audio background mode to keep the audio session active, and this worked. But when submitting the app to the app store, the app was rejected because the audio background mode is only supposed to be used for audio playback. How do I create this background mode while following Apple's guidelines?
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430
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Jan ’26
Background App Refresh
Hi, I have a couple questions about background app refresh. First, is the function RefreshAppContentsOperation() where to implement code that needs to be run in the background? Second, despite importing BackgroundTasks, I am getting the error "cannot find operationQueue in scope". What can I do to resolve that? Thank you. func scheduleAppRefresh() { let request = BGAppRefreshTaskRequest(identifier: "peaceofmindmentalhealth.RoutineRefresh") // Fetch no earlier than 15 minutes from now. request.earliestBeginDate = Date(timeIntervalSinceNow: 15 * 60) do { try BGTaskScheduler.shared.submit(request) } catch { print("Could not schedule app refresh: \(error)") } } func handleAppRefresh(task: BGAppRefreshTask) { // Schedule a new refresh task. scheduleAppRefresh() // Create an operation that performs the main part of the background task. let operation = RefreshAppContentsOperation() // Provide the background task with an expiration handler that cancels the operation. task.expirationHandler = { operation.cancel() } // Inform the system that the background task is complete // when the operation completes. operation.completionBlock = { task.setTaskCompleted(success: !operation.isCancelled) } // Start the operation. operationQueue.addOperation(operation) } func RefreshAppContentsOperation() -> Operation { }
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1.2k
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Jan ’26
Incorrect behaviour of task_info() syscall after an unrelated dlclose() call
For some reason, after invoking an unrelated dlclose() call to unload any .dylib that had previously been loaded via dlopen(..., RTLD_NOW), the subsequent call to task_info(mach_task_self(), TASK_DYLD_INFO, ...) syscall returns unexpected structure in dyld_uuid_info image_infos-&gt;uuidArray, that, while it seems to represent an array of struct dyld_uuid_info elements, there is only 1 such element (dyld_all_image_infos *infos-&gt;uuidArrayCount == 1) and the app crashes when trying to access dyld_uuid_info image-&gt;imageLoadAddress-&gt;magic, as image-&gt;imageLoadAddress doesn't seem to represent a valid struct mach_header structure address (although it looks like a normal pointer within the process address space. What does it point to?). This reproduces on macOS 15.4.1 (24E263) Could you please confirm that this is a bug in the specified OS build, or point to incorrect usage of the task_info() API? Attaching the C++ file that reproduces the issue to this email message It needs to be built on macOS 15.4.1 (24E263) via Xcode or just a command line clang++ compiler. It may crash or return garbage, depending on memory layout, but on this macOS build it doesn’t return a correct feedfacf magic number for the struct mach_header structure. Thank you Feedback Assistant reference: FB18431345 //On `macOS 15.4.1 (24E263)` create a C++ application (for example, in Xcode), with the following contents. Note, that this application should crash on this macOS build. It will not crash, however, if you either: //1. Comment out `dlclose()` call //2. Change the order of the `performDlOpenDlClose()` and `performTaskInfoSyscall()` functions calls (first performTaskInfoSyscall() then performDlOpenDlClose()). #include &lt;iostream&gt; #include &lt;dlfcn.h&gt; #include &lt;mach/mach.h&gt; #include &lt;mach-o/dyld_images.h&gt; #include &lt;mach-o/loader.h&gt; void performDlOpenDlClose() { printf("dlopen/dlclose function\n"); printf("Note: please adjust the path below to any real dylib on your system, if the path below doesn't exist!\n"); std::string path = "/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/libswiftDemangle.dylib"; printf("Dylib to open: %s\n", path.c_str()); void* handle = ::dlopen(path.c_str(), RTLD_NOW); if(handle) { ::dlclose(handle); } else { printf("Error: %s\n", dlerror()); } } void performTaskInfoSyscall() { printf("Making a task_info() syscall\n"); printf("\033[34mSource File: %s\033[0m\n", __FILE__); task_t task = mach_task_self(); struct task_dyld_info dyld_info; mach_msg_type_number_t size = TASK_DYLD_INFO_COUNT; kern_return_t kr = task_info(task, TASK_DYLD_INFO, (task_info_t)&amp;dyld_info, &amp;size); if (kr != KERN_SUCCESS) { fprintf(stderr, "task_info failed: %s\n", mach_error_string(kr)); } const struct dyld_all_image_infos* infos = (const struct dyld_all_image_infos*)dyld_info.all_image_info_addr; printf("version: %d, infos-&gt;infoArrayCount: %d\n", infos-&gt;version, infos-&gt;infoArrayCount); for(uint32_t i=0; i&lt;infos-&gt;infoArrayCount; i++) { dyld_image_info image = infos-&gt;infoArray[i]; const struct mach_header* header = image.imageLoadAddress; printf("%d ", i); printf("%p ", (void*)image.imageLoadAddress); printf("(%x) ", header-&gt;magic); printf("%s\n", image.imageFilePath); fflush(stdout); } printf("\n\n"); printf("infos-&gt;uuidArrayCount: %lu\n", infos-&gt;uuidArrayCount); for(uint32_t i=0; i&lt;infos-&gt;uuidArrayCount; i++) { dyld_uuid_info image = infos-&gt;uuidArray[i]; const struct mach_header* header = image.imageLoadAddress; printf("%d ", i); printf("%p ", (void*)image.imageLoadAddress); printf("(%x)\n", header-&gt;magic); fflush(stdout); } printf("task_info() syscall result processing is completed\n\n"); } int main(int argc, const char * argv[]) { performDlOpenDlClose(); performTaskInfoSyscall(); return 0; }
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200
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Jun ’25
utmpx reports several session for the same user
Hello, My app (daemon) time to time need to know list of GUI login sessions. According to the recommendation, I am using getutxent(). https://developer.apple.com/library/archive/qa/qa1133/_index.html However, I have faced with unclear behaviour in case of running "Migration Assistant". It can be re-created without my app. Steps to recreate: login as 'user #1' start "Migration Assistant" quit "Migration Assistant" new login prompt will be opened login as 'user #2' In spite the session of 'user #1' is closed, the command line tool "who", which gathers information from /var/run/utmpx, reports opened sessions of 'user #1'. Is it bug or feature? Thank you in advance!
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7
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314
Activity
Jul ’25
DispatchSerialQueue minimum OS support
Hi Team, We intend to create a custom serial dispatch queue targetting a global queue. let serialQueue = DispatchQueue(label: "corecomm.tallyworld.serial", target: DispatchQueue.global(qos: .default)) The documentation for DispatchQueue init does not show any minimum OS versions. BUT DispatchSerialQueue init does show iOS 17.0+ iPadOS 17.0+ Mac Catalyst macOS 14.0+ tvOS 17.0+ visionOS watchOS 10.0+. Does that mean - I will not be able to create a custom serial dispatch queue below iOS 17?
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391
Activity
Jul ’25
iOS Team Provisioning Profile” Missing UIBackgroundModes Entitlement
I’m trying to enable Background Modes (specifically for audio, background fetch, remote notifications) in my iOS SwiftUI app, but I’m getting this error: Provisioning profile “iOS Team Provisioning Profile: [my app]” doesn’t include the UIBackgroundModes entitlement. On the developer website when I make the provision profile It doesnt give me the option to allow background modes. I added it to the sign in capabilities seccion in X code and matched the bundle ID to the provision profile and certificate etc but it still runs this error because the provision profile doesnt have the entitlements..
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374
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Jul ’25
ExtensionKit & ExtensionFoundation process lifecycle
An XPC service’s process has a system-managed lifecycle: the process is launched on-demand when another process tries to connect to it, and the system can decide to kill it when system resources are low. XPC services can tell the system when they shouldn’t be killed using xpc_transaction_begin/end. Do extensions created with ExtensionFoundation and/or ExtensionKit have the same behavior?
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294
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Jul ’25
Need to start the Mac application automatically
I am developing the application in Mac. My requirement is to start the application automatically when user login. I have tried adding the plist file in launch agents, But it doesn't achieve my requirement. Please find the code added in the launch agents &lt;?xml version="1.0" encoding="UTF-8"?&gt; &lt;!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"&gt; &lt;plist version="1.0"&gt; &lt;dict&gt; &lt;key&gt;Label&lt;/key&gt; &lt;string&gt;com.sftk.secure&lt;/string&gt; &lt;key&gt;ProgramArguments&lt;/key&gt; &lt;array&gt; &lt;string&gt;/Applications/Testing.app/Contents/MacOS/Testing&lt;/string&gt; &lt;/array&gt; &lt;key&gt;RunAtLoad&lt;/key&gt; &lt;true/&gt; &lt;key&gt;KeepAlive&lt;/key&gt; &lt;false/&gt; &lt;/dict&gt; &lt;/plist&gt; I have tried by adding manually in the setting, but it was opened sometimes and closed suddenly. On open manually it works. Please provide a solution to start the application automatically on system starts
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2.1k
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Jul ’25