Hi all, I'm working on a non-interactive macOS application (a service or daemon), and I'm trying to understand the best practices around logging and error reporting, particularly in failure scenarios. If a daemon or service fails in macOS, where is it expected to log errors, and how can users or developers discover what went wrong? Specifically, I have a few questions: What is the recommended location or system for logging errors from a non-interactive macOS application? Should we use os_log, standard error output, or write directly to files somewhere? How can a user or developer access these logs to diagnose issues—should logs be visible via the Console app? Is there a standard approach to making failure information easily accessible for debugging and support, especially for daemons running under launchd? Any guidance or best practices would be appreciated.

Hi all, We're working on an iOS application and would like to improve our ability to diagnose failures - especially in scenarios where the app crashes before it can present any UI to the user. A few specific questions: In case of an exception or crash, is there a way to log the issue so the user (or our support team) can understand the cause of the failure? If the app crashes abruptly (e.g., due to a runtime exception or crash during launch), is there a recommended way to persist error information before the process terminates? Are there Apple-supported mechanisms (like crash reporting tools or APIs) we can integrate that would help us capture such issues? What’s the best practice for enabling support teams to assist users based on crash reports - especially for crashes that happen before any user interaction? Our goal is to make sure users aren't left in the dark if the app fails to start, and to allow us to deliver timely updates or support based on the cause of the crash. Thanks in advance for your guidance!

I have followed these steps as mentioned in this link :(https://developer.apple.com/forums/thread/721737) My projects app bundle structure is like this : TWGUI.app TWGUI.app/Contents TWGUI.app/Contents/_CodeSignature TWGUI.app/Contents/_CodeSignature/CodeResources TWGUI.app/Contents/MacOS TWGUI.app/Contents/MacOS/TWAgent TWGUI.app/Contents/MacOS/TWGUI TWGUI.app/Contents/Resources TWGUI.app/Contents/Library TWGUI.app/Contents/Library/LaunchAgents TWGUI.app/Contents/Library/LaunchAgents/com.example.TWGUI.agent.plist TWGUI.app/Contents/Info.plist TWGUI.app/Contents/PkgInfo TWGUI is my main GUI App , i which i want to embed TWAgent (a command line tool target) and register it using SMAppServices so that launchd can launch it. In TWGUI, code for registering to launchd using SMAppServices is structure as follow : import SwiftUI import ServiceManagement struct ContentView: View { let agent = SMAppService.agent(plistName: "com.example.TWGUI.agent.plist") var body: some View { VStack { Button("Register Agent") { RegisterAgent () } .padding() Button("Unregister Agent") { UnregisterAgent () } .padding() } } func RegisterAgent() { DispatchQueue.global(qos: .background).async { do { print("Registering Agent. Status: \(agent.status.rawValue)") try agent.register() print("Agent registered") } catch { print("Failed to register agent: \(error)") } } } func UnregisterAgent() { DispatchQueue.global(qos: .background).async { do { print("Unregistering Agent. Status: \(agent.status.rawValue)") try agent.unregister() print("Agent unregistered") } catch { print("Failed to unregister agent: \(error)") } } } } com.example.TWGUI.agent.plist : <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs$ <plist version="1.0"> <dict> <key>Label</key> <string>com.example.TWGUI.agent</string> <key>ProgramArguments</key> <array> <string>Contents/MacOS/TWAgent</string> </array> <key>RunAtLoad</key> <true/> <key>KeepAlive</key> <true/> </dict> </plist> I have used ProgramArguements instead of using Program in above plist because i was getting this error when i was using Program earlier : Registering Agent. Status: 3 Failed to register agent: Error Domain=SMAppServiceErrorDomain Code=111 "Invalid or missing Program/ProgramArguments" UserInfo={NSLocalizedFailureReason=Invalid or missing Program/ProgramArguments} TWGUI apps Info.plist is : <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>BuildMachineOSBuild</key> <string>23C71</string> <key>CFBundleDevelopmentRegion</key> <string>en</string> <key>CFBundleExecutable</key> <string>TWGUI</string> <key>CFBundleIdentifier</key> <string>com.example.TWAgent</string> <key>CFBundleInfoDictionaryVersion</key> <string>6.0</string> <key>CFBundleName</key> <string>TWGUI</string> <key>CFBundlePackageType</key> <string>APPL</string> <key>CFBundleShortVersionString</key> <string>1.0</string> <key>CFBundleSupportedPlatforms</key> <array> <string>MacOSX</string> </array> <key>CFBundleVersion</key> <string>1</string> <key>DTCompiler</key> <string>com.apple.compilers.llvm.clang.1_0</string> <key>DTPlatformBuild</key> <string></string> <key>DTPlatformName</key> <string>macosx</string> <key>DTPlatformVersion</key> <string>14.2</string> <key>DTSDKBuild</key> <string>23C53</string> <key>DTSDKName</key> <string>macosx14.2</string> <key>DTXcode</key> <string>1510</string> <key>DTXcodeBuild</key> <string>15C65</string> <key>LSMinimumSystemVersion</key> <string>14.2</string> </dict> </plist> TWAgent target has main.swift file which does this : import Foundation let startTime = CFAbsoluteTimeGetCurrent() func logTimeSinceStart() { let elapsedTime = CFAbsoluteTimeGetCurrent() - startTime NSLog("Time since program started: \(elapsedTime) seconds") } func startLoggingTime() { Timer.scheduledTimer(withTimeInterval: 1.0, repeats: true) { _ in logTimeSinceStart() } } // Start logging time startLoggingTime() // Keep the run loop running CFRunLoopRun() I followed these exact same steps in another project earlier and my agent was getting registered, although i lost that project due to some reasons. But now i am getting this error when i am registering or unregistering agent using SMAppServices from the code above : Registering Agent. Status: 3 Failed to register agent: Error Domain=SMAppServiceErrorDomain Code=1 "Operation not permitted" UserInfo={NSLocalizedFailureReason=Operation not permitted} I tried diffrent fixes for like this : Moved app bundle to /applications folder Gave permission for full disc access to this app . Code sign again (both agent and TWGUI ... But nothing seems to work , getting same error. I tried to launch agent using : Launchctl load com.example.TWGUI.agent.plist and it worked , so there is no issue with my plist implementation. Can someone help me understand how can i solve this issue ? or if i am following right steps ? Can give steps need to follow to implement this and steps so that i can register and start my agent using SMAppServices? And i also tried the project give in apples official documentation : [https://developer.apple.com/documentation/servicemanagement/updating-your-app-package-installer-to-use-the-new-service-management-api) but got same error in this project as well .

I am developing a macOS non-interactive macOS application which does not show any ui. i want to block main thread and do all the work on worker thread . Once done with work in worker thread, want to unblock main thread by exiting event loop to terminate application. Because i dont want to show any UI or use any Foundation/Cocoa functionality, i am thinking of using CFRunLoop to block main thread from exiting until i finish my work in worker thread. When i tried this in a project, I am able to finish work in worker thread after block main thread using CFRunLoop. I also want this application to be a bundled application, which can be launched by double clicking on application bundle . But when i tried it in my xcode project by launching it using double clicking on application bundle, application keeps on toggling/bouncing in the dock menu with a status "Not responding". Although i am able to complete my work in worker thread. import Foundation let runLoop = CFRunLoopGetCurrent() func workerTask() { DispatchQueue.global().async { print("do its work") sleep(5) // do some work print("calling exit event loop") CFRunLoopStop(runLoop) print ("unblocking main thread") } } workerTask () // blocking main thread print ("blocked main thread") CFRunLoopRun() print ("exit") Why i am getting this application bouncing in doc menu behavior ? I tried by using NSApplicationMain instead of CFRunLoop in my project, in that case i didnt get this behavior . Does NSApplicationMain does some extra work before starting NSRunLoop which i am not doing while using CFRunLoop, which is showing this toggling/Bouncing application icon in Dock menu ? or Is this bouncing app icon issue is related to run loop i am using which is CFRunLoop ? Note : If i dont use a bundled application and use a commandline application then i am able to do all steps in worker thread and exit main thread as i wanted after finishing my work . But i need to do all this in application which can be launched using double clicking (bundled applcation). If not by using CFRunLoop, then how can i achive this ? - Create a application which shows no UI and do all work in worker thread while main thread is blocked. Once work is done unblock main thread and exit. And user should be able to launch application using double click the application icon.

I am considering of shifting my codebase from appkit to SwiftUI entry point. In Appkit, we get control on each NSWindow. So that we can hide/resize window, close window and controll when to present a specific window . Because i have access to NSWindow instance which i can store and perform these actions. But when i shift to SwiftUI entry point, i declare struct conforming to SwiftUI Scene. And new windows will be created with the instance of this scene. I am using NSViewControllerRepresentable to add a NSViewController to the hierarchy of these scene. And adding content to this NSViewController's instance to show on screen. I need help in controlling the size of these windows. How can i close specific window ? Resize specific window ? or Hide specific window? If i use purely SwiftUI view's , then i can do this by using the Enviorment propery and use DismissWindow to close a window or openWindow with identifier to open a specific window by passing the specificer . But i am using Appkit's NSViewController where i will add buttons in heirarchy from which i want to trigger these events . And in that case how can i controll a specific window in case of multiwindow application?

In macOS application, we are using SwiftUI as an entry point to our application and attaching appdelegate using NSApplicationDelegateAdaptor. We are using NSViewControllerRepresentable to add a View Controller to the hiracrchy so that we can store intance of viewcontroller and add content to it programatically . @main struct TWMainApp: App { @NSApplicationDelegateAdaptor private var appDelegate: TWAppDelegate internal var body : some Scene { TWInitialScene () } } TWInitialScene : public struct TWInitialScene : Scene { public var body : some Scene { WindowGroup { TWInitialView () } } } TWInitialView : struct TWInitialView : View { @Environment(\.scenePhase) private var scenePhase var body : some View { TWAppKitToSwiftUIBridge () } } TWAppKitToSwiftUIBridge : struct TWNSKitToSwiftUIBridge : NSViewControllerRepresentable { func makeNSViewController(context: Context) -> TWNSViewController { let view_hierarchy : TWNSViewController view_hierarchy = TWStaticContext.sViewController return view_hierarchy } func updateNSViewController(_ nsViewController: TWNSViewController, context: Context) { } } @objc public class TWStaticContext : NSObject { public static let sViewController = TWNSViewController () public override init () {} @objc public static func GetViewController () -> TWNSViewController { return TWStaticContext.sViewController } } public class TWNSViewController : NSViewController { override public func viewDidLoad () { super.viewDidLoad () } } To add content to the hirarchy we are accessing viewcontroller's intance and adding content to it like this : public func PaintInitialScreen () { let label = NSTextField(labelWithString: "TW window") label.frame = NSRect(x: 100, y: 200, width: 200, height: 200) // Adding content to viewcontroller TWStaticContext.sViewController.view.addSubview(label) } We are using this approach because we have a contraint in our application that we have to update UI programatically and on compile time we dont know what we want to show . We will be adding content on runtime based on how many button we want, what label we want , where to place it etc. When we were using purely appKit application, doing things programatically was simple but since SwiftUI is a declarative application we have to use above approach. Rational for shifting to SwiftUI entry point is that we want our application to be future safe and since apple is more inclined to SwiffUI, we want to design our entry flow to use SwiftUI entry point . And SwiftUI being declarative, we are using appKit to add content to hiracrchy programtically. We have used similar apprach in iOS also , where are using UIApplicationDelegateAdaptor inplace of NSApplicationAdaptor . And UIViewControllerReprestable in place of NSViewControllerRepresentable. Is this right approach to use ?

In my project, i am initialising bytes with some character in cpp function, func CreateByteWithVal (), and passing to a function, func CreateNSStringFromCString(_ pPtr : UnsafeMutableRawPointer, _ pLength : Int), in swift using Swift-Cpp interop. CreateByteWithVal () allocates bytes on heap with value "AAAAAAAAAA", also calls swift function CreateNSStringFromCString. And func CreateNSStringFromCString (_ pPtr : UnsafeMutableRawPointer, _ pLength : Int) creates a NSString instance using NSString's BytesNoCopy initialiser using the bytes (pPtr) passed to it in parameter. Cpp code: void CppClass::CreateByteWithVal () { char * bytesForString = (char *) malloc (10); memset (bytesForString, 65, 10); Interop_Swift::CreateNSStringFromCString (bytesForString, 10); } Swift code: public func CreateNSStringFromCString (_ pPtr : UnsafeMutableRawPointer, _ pLength : Int) { let ns_string:NSString = NSString (bytesNoCopy: pPtr, length: pLength, encoding: String.Encoding.utf8.rawValue, freeWhenDone: false) } If we modify the byte values in memory from C++ directly, the NSString instance, which is supposed to be immutable by nature, reflects these changes. Is this approach appropriate, or is there something we're overlooking or need to address? In our project, we are mutating the byte values directly like this, and the changes are being reflected in the NSString instance : memset (bytesForString, 66, 5); Essentially, I want to confirm whether we can use this method to modify values through C++ without directly mutating the NSString instance. For the UI, we'll be reading the NSString instance by creating a native Swift String instance from it, like this: let str:String = ns_string as String Will the value of str remain consistent as long as we ensure that the correct bytes are provided by C++?

I want to understand how it manages memory allocation if i need more memory later than the memory i specified during initialisation . Does it allocates new chunk of memory and dellocate older memory or does it already allocated more memory than i asked for in first place? Just want to understand how exactly this calculation is done ? And i do initialisation of NSMutableString in swift , will these same principle of expension applied there ?

When user enters in a textfield, is the input of textfield gets stored in a String ? If yes, then String in swift being immutable, as user keeps on typing does new memory for storing that text gets allocated with each key stroke ? And when we read users input by using delegate method textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) from textfield.text, we get users input in a String. Is it same storage as used by textfield for storing the user input on key stroke or is it some other storage with copy of the user's input in it? Or is UItextfield using a diffrent data structure (buffer) for storing the user input and when we do textfield.text, it gives a copy of data stored in original buffer?

When i create a intance of swift String : Let str = String ("Hello") As swift String are immutable, and when we mutate the value of these like: str = "Hello world ......." // 200 characters Swift should internally allocate new memory and copy the content to that buffer for update . But when i checked the addresses of original and modified str, both are same? Can you help me understand how this allocation and mutation working internally in swift String?

In below Swift code , is there any possiblities of failure of Unmanaged.passRetain and Unmanaged.takeRetain calls ? // can below call fail (constructor returns nil due to OS or language error) and do i need to do explicit error handling here? let str = TWSwiftString(pnew) // Increasing RC by 1 // can below call fail (assuming str is valid) and do i need to do explicit error handling for the same ? let ptr:UnsafeMutableRawPointer? = Unmanaged.passRetained(str).toOpaque() // decrease RC by 1 // can below call fail (assuming ptr is valid) ? and do i need to do explicit error handling Unmanaged<TWSwiftString>.fromOpaque(pStringptr).release()

In my project, i have a Swift class with a class level property of type string. Like this : class TWSwiftString { var pString:String! init(_ pString: String) { self.pString = pString } } I am creating intance of this class and then creating a opaque pointer to this intance. Like this : let str = TWSwiftString("World") // Increasing RC by 1 strptr = Unmanaged.passRetained(str).toOpaque() Now using this opaque pointer i want to modify the value of pString by directly operating on memory. Like this: withUnsafeMutablePointer(to: &strptr.pString) { strPointer in strPointer.pointee = "World" } Although i am able to modify pString like this and print. Lets assume i have a approach to make sure memory remains valid when it is operated on and freeing of memory is also handled somehow . Will this approach work if i have 100s of intance of this string which are being operated in this manner ? What if the size of new value is greater than existing string value ? For this i am thinking of chunk of memory initially and then keep on increasing size of it as bigger string then this chunk comes. Does this approach seems feasible ? Any other problems i can encounter by using this approach ? Chatgpt gave this answer : To directly update the memory of a Swift class’s property, particularly to alter a String property, is generally discouraged due to Swift's memory safety model. However, if we want to access and modify a class property directly, the best practice is to use a property accessor, as manually altering memory could lead to undefined behavior or even crashes. Why Direct Memory Manipulation Is Risky When you attempt to manipulate memory directly, especially with Swift’s memory model, you might alter not only the value but also the memory layout of Swift’s String type, which could break things internally. The Swift compiler may store String differently based on the internal structure, so even if we manage to locate the correct memory address, directly modifying it is unreliable. do you have any opinion around chatgpt resoponse ?

For calling swift api of a class to cpp , we need to include SwiftInterfaceGeneratedHeader to cpp file and then we can access swift class api in cpp . Signature of swift class with public apis will be added to the SwiftInterfaceGeneratedHeader. We find an odd behaviour here . Signature of classes will be added to SwiftInterfaceGeneratedHeader in alphabetical order (swift class name alphabetically lower will be added first to generated header). If we have a swift class which is referenced by another swift class Api , then referenced class's name should be alphabetically lower that referee class , otherwise we will get a build error :- "Unknown class name". public class A { public func funca () { print ("class A") } } public class B { public func funcb () { print ("class B") } public func funcb2 (pA:A) { pA.funca() } public func funcb3 (pC:C) { pC.funcc() } } public class C { public func funcc () { print ("class C") } } Cpp class where we include bridging header after turning on swift cpp interop : class Test1 { public: static void testfunc (); }; #include "Test1.hpp" #include "cppswiftinterop-Swift.h" void Test1::testfunc() { } Here , we have three swift classes , Class A,B,C. And since we are including SwiftInterfaceGeneratedHeader in cpp , signature of these class will be added to the generated header . In this project , we are referencing Class A and Class C from Class B . And since A is alphabetically lower that B , it works fine (because signature of A in Generated header will be added before it is referenced by B). But since C is alphabetically above than B , it will through build error (Unknown type name 'C') , because Signature of C in Generated header will be added after it is referenced by class B). If i rename Class C to Class AA then , it works fine. Is this a bug in swift cpp interop?

For printing from worker thread to a UIPrinter(whose url i have saved ) i am doing this and able to print : func PrintPdfDocument (pDocument:Data) { // Create a print interaction controller let printController = UIPrintInteractionController.shared // Set the printing options let printInfo = UIPrintInfo(dictionary:nil) printInfo.jobName = "Print Job " printController.printInfo = printInfo printController.showsPageRange = true // Set the PDF document to be printed printController.printingItems = pDocument printController.print(to: defaulttprinter, completionHandler: { (controller, completed, error) in if completed { print("Printing successful!") } else { if let error = error { print("Printing failed with error: \(error.localizedDescription)") } else { print("Printing was canceled.") } } }) } When i call PrintPdfDocument (pDocument:Data) function , more than once with diffrent data shown below : DispatchQueue.global().async { PrintPdfDocument (pDocument:data1) } DispatchQueue.global().async { PrintPdfDocument (pDocument:data2) } DispatchQueue.global().async { PrintPdfDocument (pDocument:data3) } Printer is printing only one document(data1) . For other call is not executing printController.print (to....) function inside PrintPdfDocument.

I have a tvOS project contains an App target and 3 static libraries: EntryPoint – Static library that contains main , AppDelegate and SceneDelegate Experience – Static library containing my UI elements AppTarget – executable built using above two libraries I have a class "SelectionTable" which subclasses UITableView in Experience target : import UIKit class SelectionTable : UITableView { private var vDataSrc:[String]! func SetDataSrc (_ pDataSrc:[String]) { self.vDataSrc = pDataSrc } func UpdateDataSrc (_ pStringList:[String]) { self.vDataSrc += pStringList } func GetDataSrc () -> [String] { return self.vDataSrc } } I am not using this class anywhere and still i am getting these errors when i build my AppTarget: Cannot find interface declaration for 'UITableView', superclass of 'SelectionTable' Expected a type These above error are coming in generated header file "Experience-Swift.h". This file is auto-generated by compiler. I am not using @objc anywhere in the code, But still the Target-Swift.h file has the below lines: SWIFT_CLASS("_TtC10Experience22SelectionTable") @interface SelectionTable : UITableView - (nonnull instancetype)initWithFrame:(CGRect)frame style:(UITableViewStyle)style OBJC_DESIGNATED_INITIALIZER; - (nullable instancetype)initWithCoder:(NSCoder * _Nonnull)coder OBJC_DESIGNATED_INITIALIZER; @end When i am marking above class as Private , this error goes away . And also , if i am defining SelectionTable class in EntryPoint library , this error does not occur . I am using similar model for an iOS project also and there i am not facing this issue. I am using :- Swift version : Swift 5.9.2 XCode version : 15.2