My app is for personal use currently, so distribution won't be a problem. It registers a privileged helper using SMAppService, and I was wondering whether there is a way to customize the authorization dialog that the system presents to the user.
Processes & Concurrency
RSS for tagDiscover how the operating system manages multiple applications and processes simultaneously, ensuring smooth multitasking performance.
Selecting any option will automatically load the page
Post
Replies
Boosts
Views
Activity
My app uses SMAppService to register a privileged helper, the helper registers without errors, and can be seen in System Settings. I can get a connection to the service and a remote object proxy, but the helper process cannot be found in Activity Monitor and the calls to the proxy functions seem to always fail without showing any specific errors. What could be causing this situation?
Basically the title. I am trying to implement a local notification to trigger, regardless of internet connection, around 3-5pm if a certain array in the app is not empty to get the user to sync unsaved work with the cloud. I wanted to used the BGAppRefreshTask as I saw it was lightweight and quick for just posting a banner notification but after inspecting it in the console, it looks like it needs internet connection to trigger. Is this the case or am I doing something wrong? Should I be using the BGProcessingTask instead?
Topic:
App & System Services
SubTopic:
Processes & Concurrency
Tags:
Background Tasks
User Notifications
Hello 👋
Our team added com.apple.security.temporary-exception.apple-events: com.apple.Terminal recently to our Mac app to be able to tell the terminal to execute a specific command line automatically for the user when clicking a button but we've been rejected during review because of this entitlement so for now we've deleted it and deleted the associated feature.
It concerns the following feature (see attachment).
Context:
Among other things the application enable to review pull request changes (remote) and we would like a button to automatically clone the pull request on disk when user click a button. We would like to use terminal for security reason as when cloning using git command we need ssh keys or other credential and there's no reason (rather than technical ones) that the user provide us such private information that is stored in the ~/.ssh. We prefer think the other way around and tell the user what to execute instead (no credentials involved or shared).
We referred to: https://developer.apple.com/library/archive/documentation/Miscellaneous/Reference/EntitlementKeyReference/Chapters/AppSandboxTemporaryExceptionEntitlements.html
I admit it's unclear for me if this will imply a 100% rejection or if these entitlements are deprecated.
Is "com.apple.security.temporary-exception.apple-events: com.apple.Terminal" an entitlement that is reserved for special Apple partners ?
Is it an entitlement that we should demonstrate usage first ? Or should we completely remove the feature if we distribute through the App Store ?
Is Apple advice for other APIs to develop such features (execute command line for the user) when distributing through the App Store ?
As said we've disabled the feature for now.
Thank you in advance for those who will take time to answer this,
I've discovered that a system network extension can communicate with a LaunchDaemon (loaded using SMAppService) over XPC, provided that the XPC service name begins with the team ID.
If I move the launchd daemon plist to Contents/Library/LaunchAgents and swap the SMAppService.daemon calls to SMAppService.agent calls, and remove the .privileged option to NSXPCConnection, the system extension receives "Couldn't communicate with a helper application" as an error when trying to reach the LaunchAgent advertised service. Is this limitation by design?
I imagine it is, but wanted to check before I spent any more time on it.
Topic:
App & System Services
SubTopic:
Processes & Concurrency
Tags:
Service Management
XPC
System Extensions
Network Extension
I'm developing a safety-critical monitoring app that needs to fetch data from government APIs every 30 minutes and trigger emergency audio alerts for threshold violations.
The app must work reliably in background since users depend on it for safety alerts even while sleeping.
Main Challenge: iOS background limitations seem to prevent consistent 30-minute intervals. Standard BGTaskScheduler and timers get suspended after a few minutes in background.
Question: What's the most reliable approach to ensure consistent 30-minute background monitoring for a safety-critical app where missed alerts could have serious consequences?
Are there special entitlements or frameworks for emergency/safety applications?
The app needs to function like an alarm clock - working reliably even when backgrounded with emergency audio override capabilities.
Topic:
App & System Services
SubTopic:
Processes & Concurrency
Tags:
Network
AVAudioSession
Background Tasks
Hello,
We're seeing some strange crashes and noticed the following. It's unclear if related or not.
The contract for xpc_main, which internally calls dispatch_main, is This function never returns. and they are appropriately peppered with __attribute__((__noreturn__)). Documentation states:
This function “parks” the main thread and waits for blocks to be submitted to the main queue.
However, internally, dispatch_main calls pthread_exit. pthread_exit's documentation states that:
After a thread has terminated, the result of access to local (auto)
variables of the thread is undefined. Thus, references to local
variables of the exiting thread should not be used for the
pthread_exit() value_ptr parameter value.
I'd say the two contracts of This function never returns. and thread exiting with its storage released are diametrically opposed and can create nuanced issues.
Consider the following code:
struct asd {
int a;
};
struct asd* ptr;
void fff(void* ctx)
{
while(true)
{
printf("%d\n", ptr->a);
ptr->a = (ptr->a + 1);
usleep(100000);
}
}
int main(int argc, const char * argv[]) {
struct asd zxc;
zxc.a = 1;
ptr = &zxc;
dispatch_async_f(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), NULL, fff);
dispatch_main();
return 0;
}
This is a gross over-simplification of the code we have, but in the same "spirit". We have a C++ object that is created on the stack and exposes one of its members as a global pointer, with the assumption that it would never release. What I understand from This function never returns is that the calling thread remains dormant and its stack remains alive. What I understand from pthread_exit is that the thread is killed (this is verified with a debugger attached) and its stack storage is released.
Another thing that is throwing me off is that no sanitizer that is provided by clang/Xcode catches this issue. I don't see any special handling of the internal pthread_t in libdispatch to keep the stack storage alive.
Our code is more complex, but can be solved by allocating the initial object on the heap, rather than on the stack. But still I would like to understand if this is the expected behavior. Perhaps my preconception of __attribute__((__noreturn__)) is wrong, and accessing stack variables post call to a __attribute__((__noreturn__)) function is UB?
Thanks
Topic:
App & System Services
SubTopic:
Processes & Concurrency
Every time macOS goes to sleep the processes get suspended which is expected. But during the sleep period, all processes keep coming back and they all get a small execution window where they make some n/w requests. Regardless of what power settings i have. It also does not matter whether my app is a daemon or not
Is there any way that i can disable this so that when system is in sleep, it stays in suspended, no intermittent execution window? I have tried disabling Wake for network access setting but processes still keep getting intermittent execution window.
Is there any way that i can prevent my app from coming back while in sleep. I don't want my app to get execution window, perform some executions and then get suspended not knowing when it will get execution window again?
The application is placed into the idle state. Subsequently, the device enters a sleep state.
While the device is in sleep, App start background task within the application successfully receives its expirationHandler callback.
App received the expiration callback and App called the end BGtask
OS did not released the Assertion.
Resulting in App getting terminated by the OS for exceeding the BG task
Apple Feedback- FB19192371
Testing Environment:
iOS Version: 26.0 Beta 7
Xcode Version: 17.0 Beta 6
Device: iPhone 16 Pro
Description:
We are implementing the new BGContinuedProcessingTask API and are using the wildcard identifier notation as described in the official documentation. Our Info.plist is correctly configured with a permitted identifier pattern, such as com.our-bundle.export.*.
We then register a single launch handler for this exact wildcard pattern. We are performing this registration within a UIViewController, which is a supported pattern as BGContinuedProcessingTask is explicitly exempt from the "register before applicationDidFinishLaunching" requirement, according to the BGTaskScheduler.h header file. The register method correctly returns true, indicating the registration was successful.
However, when we then try to submit a task with a unique identifier that matches this pattern (e.g., com.our-bundle.export.UUID), the BGTaskScheduler.shared.submit() call throws an NSInternalInconsistencyException and terminates the app. The error reason is: 'No launch handler registered for task with identifier com.our-bundle.export.UUID'.
This indicates that the system is not correctly matching the specific, unique identifier from the submit call to the registered wildcard pattern handler. This behavior contradicts the official documentation.
Steps to Reproduce:
Create a new Xcode project.
In Signing & Capabilities, add "Background Modes" (with "Background processing" checked) and "Background GPU Access".
Add a permitted identifier (e.g., "com.company.test.*") to BGTaskSchedulerPermittedIdentifiers in Info.plist.
In a UIViewController's viewDidLoad, register a handler for the wildcard pattern. Check that the register method returns true.
Immediately after, try to submit a BGContinuedProcessingTaskRequest with a unique identifier that matches the pattern.
Expected Results:
The submit call should succeed without crashing, and the task should be scheduled.
Actual Results:
The app crashes immediately upon calling submit(). The console shows an uncaught NSInternalInconsistencyException with the reason: 'No launch handler registered for task with identifier com.company.test.UUID'.
Workaround:
The issue can be bypassed if we register a new handler for each unique identifier immediately before submitting a request with that same unique identifier. This strongly suggests the bug is in the system's wildcard pattern-matching logic.
I'm working on a Mac app that receives a process ID via NSXPCConnection, and I'm trying to figure out the best way to determine whether that process is a native macOS app like Safari—with bundles and all—or just a script launched by something like Node or Python. The executable is signed with a Team ID using codesign.
I was thinking about getting the executable's path as one way to handle it, but I’m wondering if there’s a more reliable method than relying on the folder structure.
Topic:
App & System Services
SubTopic:
Processes & Concurrency
Tags:
XPC
Inter-process communication
I'm developing a macOS console application that uses ODBC to connect to PostgreSQL. The application works fine when run normally, but fails to load the ODBC driver when debugging with LLDB(under root works fine as well).
Error Details
When running the application through LLDB, I get this sandbox denial in the system log (via log stream):
Error 0x0 0 0 kernel: (Sandbox) Sandbox: logd_helper(587) deny(1) file-read-data /opt/homebrew/lib/psqlodbcw.so
The application cannot access the PostgreSQL ODBC driver located at /opt/homebrew/lib/psqlodbcw.so(also tried copy to /usr/local/lib/...).
Environment
macOS Version: Latest Sequoia
LLDB: Using LLDB from Xcode 16.3 (/Applications/Xcode16.3.app/Contents/Developer/usr/bin/lldb)
ODBC Driver: PostgreSQL ODBC driver installed via Homebrew
Code Signing: Application is signed with Apple Development certificate
What is the recommended approach for debugging applications that need to load dynamic libraries?
Are there specific entitlements or configurations that would allow LLDB to access ODBC drivers during debugging sessions?
Any guidance would be greatly appreciated.
Thank you for any assistance!
Hello im creating an expo module using this new API, but the problem i found currently testing this functionality is that when the task fails, the notification error doesn't go away and is always showing the failed task notification even if i start a new task and complete that one.
I want to implement this module into the production app but i feel like having always the notification error might confuse our users or find it a bit bothersome.
Is there a way for the users to remove this notification?
Best regards!
I work for a large medical device company.
We have a 1st party BLE enabled medical device that must be very battery efficient. To this end, if a connection is lost, the BLE radio is powered down after 60 seconds and will only turn back on when a physical button on the device is pressed.
I've been tasked with connecting to the device, staying connected to the device, and being able to retrieve data from the device upon a timed action. For instance, this could include a data read and transmission while they sleep. The key part of this is staying reliably connected for extended periods of time.
This is a BYOD setup, and we cannot control power profiles.
I would very much appreciate any information, recommendations, and/or insights into solving this problem.
Thanks!
Topic:
App & System Services
SubTopic:
Processes & Concurrency
Tags:
External Accessory
iOS
Application Services
Core Bluetooth
In iOS Background Execution limits, I see this:
When the user ‘force quits’ an app by swiping up in the multitasking UI, iOS interprets that to mean that the user doesn’t want the app running at all. iOS also sets a flag that prevents the app from being launched in the background. That flag gets cleared when the user next launches the app manually.
However, I see that when I close an app on iPadOS 26 with the red X, the app doesn't appear in the multitasking UI. So are they treated as force closes and prevented from running background tasks?
Some users of my Mac app are complaining of redrawing delays. Based on what I see in logs, my GCD timer event handlers are not being run in a timely manner although the runloop is still pumping events: sometimes 500ms pass before a 15ms timer runs. During this time, many keypresses are routed through -[NSApplication sendEvent:], which is how I know it's not locked up in synchronous code.
This issue has not been reported in older versions of macOS.
I start the timer like this:
_gcdUpdateTimer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0, dispatch_get_main_queue());
dispatch_source_set_timer(_gcdUpdateTimer,
dispatch_time(DISPATCH_TIME_NOW, period * NSEC_PER_SEC),
period * NSEC_PER_SEC,
0.0005 * NSEC_PER_SEC);
dispatch_source_set_event_handler(_gcdUpdateTimer, ^{
…redraw…
});
Hi,
We are running into issues with iOS app prewarming, where the system launches our app before the user has entered their passcode.
In our case, the app stores flags, counters, and session data in UserDefaults and the Keychain. During prewarm launches:
UserDefaults only returns default values (nil, 0, false). We have no way of knowing whether this information is valid or just a placeholder caused by prewarming.
Keychain items with kSecAttrAccessibleAfterFirstUnlockThisDeviceOnly are inaccessible, which can lead to broken business logic (the app can assume no session exists).
No special launch options or environment variables appear to be set.
We can reproduce this 100% of the time by starting a Live Activity in the app before reboot.
Here’s an example of the workaround we tried, following older recommendations:
__attribute__((constructor))
static void ModuleInitializer(void) {
char* isPrewarm = getenv("ActivePrewarm");
if (isPrewarm != NULL && isPrewarm[0] == '1') {
exit(0); // prevent prewarm launch from proceeding
}
}
On iOS 16+, the ActivePrewarm environment variable doesn’t seem to exist anymore (though older docs and SDKs such as Sentry reference it).
We also tried listening for UIApplication.protectedDataDidBecomeAvailableNotification, but this is not specific to prewarming (it also fires when the device gets unlocked) and can cause watchdog termination if we delay work too long.
Questions:
Is there a supported way to opt out of app prewarming?
What is the correct way to detect when an app is being prewarmed?
Is the ActivePrewarm environment variable still supported in iOS 16+?
Ideally, the UserDefaults API itself should indicate whether it is returning valid stored values or defaults due to the app being launched in a prewarm session.
We understand opting out may impact performance, but data security and integrity are our priority. Any guidance would be greatly appreciated.
Hello everyone,
I’m a new developer still learning as I go. I’m building a simple watchOS app that tracks Apple Watch battery consumption, records hourly usage data, and uses that information to predict battery life in hours.
I’ve run into an issue where background refresh completely stalls after charging and never recovers, regardless of what I do. The only way to restore normal behavior is to restart the watch.
Background refresh can work fine for days, but if the watch is charging and a scheduled background refresh tries to run during that period, it appears to be deferred—and then remains in that deferred state indefinitely. Even reopening the app or scheduling new refreshes doesn’t recover it.
Has anyone else encountered this behavior? Is there a reliable workaround?
I’ve seen a few reports suggesting that there may be a regression in scheduleBackgroundRefresh() on watchOS 26, where tasks are never delivered after certain states.
Any insights or confirmations would be greatly appreciated. Thank you!
I am currently developing a macOS app that can show system HUDs in the Notch
Till Sequoia I used to kill the OSDUIHelper process (which displays the default macOS Volume and Brightness control HUDs) - and replaced it with my app's HUDs
But, it is not working on macOS Tahoe anymore as the OSDUIHelper process is no longer there due to the UI changes
Has the process been renamed - or is there any other way to kill the process?
Topic:
App & System Services
SubTopic:
Processes & Concurrency
Tags:
Swift
macOS
SwiftUI
Background Tasks
First, our app communicates with our blood glucose monitor (CGM) using Bluetooth Low Energy (BLE).
On an iPhone 14 Pro with iOS 26.0.1, Bluetooth communication works properly even when the app is in the background and locked. Even if the phone and CGM are disconnected, the app continues to scan in the background and reconnects when the phone and CGM are back in close proximity. It won't be dormant in the background or when the screen is locked. This effectively ensures that diabetic users can monitor their blood glucose levels in real time.
However, after using iOS 26.0.1 on the iPhone 17, we've received user feedback about frequent disconnections in the background. Our logs indicate that Bluetooth communication is easily disconnected when switching to the background, and then easily dormant by the system, especially when the user's screen is locked. This situation significantly impacts users' blood glucose monitoring, and users are unacceptable. What can be done?
Topic:
App & System Services
SubTopic:
Processes & Concurrency
Tags:
IOBluetooth
Background Tasks
Core Bluetooth