Background I have a SwiftUI app that uses OSLog and the new Logger framework. In my SwiftUI views, I would like to use something like Self._logChanges() to help debug issues. After some trial and error, I can see the messages appear in the System console log for the app I am debugging using the com.apple.SwiftUI subsystem. Problem I'd like to see those same messages directly in Xcode's console window so I can filter them as needed. How do I do that? Thanks! -Patrick

Hi, Our team is facing an issue where the os log message is not fully printed in the Xcode console. Even when using Debug → Attach to Process by PID or Name, the logs appear truncated (Both simulator and physical device). We noticed that the Xcode 15.0 release notes we saw that there is some truncation made for debug lines in console. We also tried checking the logs using Console.app, but the truncation remains. If limitation is there how much maximum lines it can print ? Could anyone please provide guidance on how we can view the complete logs? Any suggestions or workarounds would be highly appreciated.

I'd like to give control to the app developer that uses my library to select which level of logs they'd like to see from my lib (e.g. do they want to see all debug messages or just errors). I know there are filtering controls that Xcode gives us, but I'm wondering if there is a way to pull this off with code. Ideally the user callsite would look like MyLib(logLevel: .info). And then I would pass that info level somehow to OSLog. Today, I create my logger like this: let myLogger = Logger( subsystem: Bundle.main.bundleIdentifier ?? "UnknownApp", category: "MyLibrary" ) As far as I can tell, there is nothing I can then pass to my myLogger instance to configure the threshold level. I'm imagining an interface like: myLogger.logLevel(.warning) // Later... myLogger.debug("You won't see this") myLogger.error("But you will see this") Does OSLog and friends give us any ability to do this out of the box, or are we building little wrappers around OSLog to accomplish this? Thank you, Lou

I was using os_log in my code and in header of oslog, it has been mentioned that there is physical cap of 1024 bytes per log line for dynamic content. So I was looking for a work around but before that I am not able see the truncation when I tried creating this issue. let baseString = String(repeating: "a", count: 1020) let criticalMarker = "LAST_5_BYTES" let testString = baseString + criticalMarker // 1020 + 12 = 1032 bytes os_log("LONG_STRING: %@", testString) I used this as a sample code to check the truncation but in Xcode debugger it logs all the 1020 bytes and the last 12 bytes as well. I even checked the console and there also it was logging all the bytes. Can anyone help me with this as to what I am missing here?

Hello, I am a student studying accessibility. I aim to analyze the smartphone usage patterns of visually impaired individuals. Therefore, I would like to log the VoiceOver usage records of visually impaired iPhone users. Is there a way to output VoiceOver logs, similar to the AccessibilityService API on Android? Thank you in advance for your responses.

Is it just me or does running SwiftUI apps using Xcode 16 give so many warnings and errors in the console that it's impossible to debug everything? Even the simplest gestures such as a long press generate a warning. I'm starting to ignore them, which feels negligent. Any insights/tips?

When I set the option parameter to OSLogEnumeratorReverse, the iteration order of OSLogEnumerator is still from front to back in time When I set the options parameter to 0 and the position parameter to the first 5 seconds of the current time, OSLogEnumerator can still iterate over the previous 5 seconds #import "ViewController.h" #import <OSLog/OSLog.h> @interface ViewController () @property(strong, nonatomic)OSLogStore *logStore; @property(strong, nonatomic)NSDateFormatter *formatter; @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; NSError *err = nil; self.logStore = [OSLogStore storeWithScope:OSLogStoreCurrentProcessIdentifier error:&err]; if (!self.logStore || err) { NSLog(@"error: %@", err); NSAssert(0, @""); } self.formatter = [[NSDateFormatter alloc] init]; [self.formatter setDateFormat:@"[yyyy-MM-dd HH:mm:ss:SSS]"]; } - (IBAction)addLog:(id)sender { static int i = 0; NSLog(@"[test] %@ this is a log with index:%d", [self.formatter stringFromDate:[NSDate date]], i++); } - (IBAction)printLogWithReverse:(id)sender { NSError *err = nil; NSPredicate *preeicate = [NSPredicate predicateWithFormat:@"composedMessage contains %@" argumentArray:@[@"[test]"]]; OSLogEnumerator *enumer = [self.logStore entriesEnumeratorWithOptions:OSLogEnumeratorReverse position:nil predicate:preeicate error:&err]; if (err) { NSLog(@"enumer error:%@", err); NSAssert(0, @""); } OSLogEntryLog *entry = nil; while (entry = [enumer nextObject]) { NSString *message = [entry composedMessage]; printf("log: %s\n", message.UTF8String); } } - (IBAction)printLogWithPosition:(id)sender { NSError *err = nil; NSPredicate *preeicate = [NSPredicate predicateWithFormat:@"composedMessage contains %@" argumentArray:@[@"[test]"]]; NSDate *posDate = [NSDate dateWithTimeIntervalSinceNow:-5]; OSLogPosition *pos = [self.logStore positionWithDate:posDate]; OSLogEnumerator *enumer = [self.logStore entriesEnumeratorWithOptions:0 position:pos predicate:preeicate error:&err]; if (err) { NSLog(@"enumer error:%@", err); NSAssert(0, @""); } const char *now = [self.formatter stringFromDate:[NSDate date]].UTF8String; const char *posStart = [self.formatter stringFromDate:posDate].UTF8String; OSLogEntryLog *entry = nil; while (entry = [enumer nextObject]) { NSString *message = [entry composedMessage]; printf("log(now:%s, pos:%s): %s\n", now, posStart, message.UTF8String); } } @end The method of - (IBAction)printLogWithReverse:(id)sender print result not reversed by time. log: [test] [2025-02-18 17:35:50:175] this is a log with index:0 log: [test] [2025-02-18 17:35:51:040] this is a log with index:1 log: [test] [2025-02-18 17:35:51:174] this is a log with index:2 log: [test] [2025-02-18 17:35:51:323] this is a log with index:3 log: [test] [2025-02-18 17:35:51:473] this is a log with index:4 log: [test] [2025-02-18 17:35:51:640] this is a log with index:5 log: [test] [2025-02-18 17:35:51:773] this is a log with index:6 log: [test] [2025-02-18 17:35:51:923] this is a log with index:7 The method of - (IBAction)printLogWithPosition:(id) print result should not contain the log from 5 seconds ago because I set the start time position in the position argument [test] [2025-02-18 17:43:58:741] this is a log with index:0 [test] [2025-02-18 17:43:58:940] this is a log with index:1 [test] [2025-02-18 17:43:59:458] this is a log with index:2 [test] [2025-02-18 17:43:59:923] this is a log with index:3 log(now:[2025-02-18 17:44:51:132], pos:[2025-02-18 17:44:46:032]): [test] [2025-02-18 17:43:58:741] this is a log with index:0 log(now:[2025-02-18 17:44:51:132], pos:[2025-02-18 17:44:46:032]): [test] [2025-02-18 17:43:58:940] this is a log with index:1 log(now:[2025-02-18 17:44:51:132], pos:[2025-02-18 17:44:46:032]): [test] [2025-02-18 17:43:59:458] this is a log with index:2 log(now:[2025-02-18 17:44:51:132], pos:[2025-02-18 17:44:46:032]): [test] [2025-02-18 17:43:59:923] this is a log with index:3

Hello, I'm developing a Transparent Proxy and I noticed that the Network Extension Framework logs in the Unified Logging System when my profile receives a flow, its source application, its destination endpoint, and my profile's decision regarding that flow. I worry that this may compromise the user's privacy. So is there a way that I can turn off these logs at least in Distribution Configurations?

Hello, I'm seeing many errors like this in the Xcode debug console when I build and run my app: ERROR: Unrecognized attribute string flag '?' in attribute string "T@"NSString",?,R,C" for property debugDescription The app project makes heavy use of Logger(), and I suspect it is related to that logging in some way, but I haven't been able to narrow down the issue to specific log calls. I have Category, Subsystem and Timestamp enabled in the Xcode console, but none of those are displayed for this output. What causes this? Or how can I better narrow down the source?

Hi: Our group would like to forward logs from our Macs in our integration/production environments to a central server. I haven't found any good documentation for this yet. Can anyone point me to a way to forward to a Graylog or syslog-based server? We're not against cobbling together an app or script using "log stream" to send the info ourselves, but that seems extreme for what I'd think is a very common use case.

I have os_log statements in my app. With my phone connected to the Mac, when I run the app through XCode, open Console app, those logs are shown. However, when I'm launching the app on its own, those logs don't appear in Console (phone still connected). Am I missing something very basic? Please help.

Hi, I'm developing a multi-platform project in Windows, Mac and Linux. I am trying to create a wrapper class in Go that will query system information and history. I see that the Unified Logging System is a sophisticated way to get all sorts of kernel information (and even a long history including rotated logs). However, I am struggling to see how I can use the APIs in other languages aside from Swift itself (or C). I do not want to use the log or last commands to query information in separate child processes in my project. I would like to simply query the database itself, similar to using OSLog in Swift. If this is something that is entirely proprietary or not possible, let me know :)

I'm trying to diagnose an issue with a Message Filtering Extension not working. The associated domain for the server is not currently publicly hosted, so the associated domains specified for the app are postpended with ?mode=developer On application installation I filtered OS logging by the swcd process and saw this logged: debug 08:40:01.125071-0800 swcd Skipping domain vz….qa….cl….ce….com?mode=developer because developer mode is disabled But developer mode IS enabled on the phone (Settings/Privacy &amp; Security/Developer Mode is set to On). Therefore why is swcd saying developer mode is disabled? Is the developer mode mentioned in the documentation not actually the Developer Mode in the iPhone's setting but something else? That wouldn't appear to be the case because the documentation explicitly states "Specifies that only devices in developer mode can access the domain." Full Documentation: https://developer.apple.com/documentation/BundleResources/Entitlements/com.apple.developer.associated-domains If you use a private web server, which is unreachable from the public internet, while developing your app, enable the alternate mode feature to bypass the CDN and connect directly to your server. To do this, add a query string to your associated domains entitlement, as shown in the following example: :?mode= developer Specifies that only devices in developer mode can access the domain. So I've: turned developer mode on for the device have added ?mode=developer to the domain am building/running using a developer certificate. But why does swcd log that developer mode is disabled?

I'm getting literally hundreds and hundreds of these lines appearing in the Xcode console when running the app. What's the cause? Too much logging? (if so this didn't used to appear with earlier version of Xcode, I'm currently running Xcode 16.2) How to do this: "set IDELogRedirectionPolicy to oslogToStdio in the environment of the executable." And what does doing that do? <snip> 1 log/signpost messages lost due to high rates in live mode recording. To guarantee delivery of all logs, set IDELogRedirectionPolicy to oslogToStdio in the environment of the executable. 1 log/signpost messages lost due to high rates in live mode recording. To guarantee delivery of all logs, set IDELogRedirectionPolicy to oslogToStdio in the environment of the executable. <snip>

Pretty sure this is a no-no, but asking just in case there's an easy way to make this work struct DocumentContentView: View { private static let logger = Logger( subsystem: "mySubsystem", category: String(describing: Self.self) ) var body: some View { VStack { Text("Hello") logger.trace("hello") } } } This code generates the following compile error at the logger.trace line buildExpression is unavailable: this expression does not conform to View I suspect every line of the body var (or any @ViewBuilder - designated code?) needs to 'return' a View. Is this correct? or more importantly any work arounds other than putting some/all of the view contents in a. func()?

Something (or a lot) is janky about apps built for "My Mac - designed for iPad." Aside from things just not working, the amount of garbage spewed to the console during debugging is unmanageable. I can't see my own trace statements amongst screens and screens of repetitive nonsense. I right-clicked on it and set it to filter out errors, but I'd like to get notified of legitimate errors. Anyone employing a clever filtering method I'm not aware of?

Hello Apple support, We are trying to figure out how to persist the activity logs and retrieve it. It seems the obvious place to find them is "Analytics &amp; Improvements" in settings. How are the .ips log generated? (OSLog?) What are the conditions for the iOS to store the logs? We are aware of this post, but no info on the storage of logs