OSLog is a unified logging system for the reading of historical data.

Posts under OSLog tag

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On Log Noise - Debugging
I came across several "errors" being reported when I run my app, however my app seems to function correctly. I believe they fall in the category listed on this ( now locked ) thread https://developer.apple.com/forums/thread/115461 However, I wanted to post the ones I found to clarify ( close to submission) just in case any of these end up being more than just log noise later. PLEASE let me know if you've come across these before and whether they impacted anything or if you can confirm they are just log noise. Thanks in advance! -[RTIInputSystemClient remoteTextInputSessionWithID:performInputOperation:] perform input operation requires a valid sessionID. inputModality = Keyboard, inputOperation = , customInfoType = UIEmojiSearchOperations AVAudioSession_iOS.mm:2,223 Server returned an error from destroySession:. Error Domain=NSCocoaErrorDomain Code=4099 “The connection to service with pid 102 named com.apple.audio.AudioSession was invalidated from this process.” UserInfo={NSDebugDescription=The connection to service with pid 102 named com.apple.audio.AudioSession was invalidated from this process. CAReportingClient.mm:532 Attempted to remove a reporter not created by this client { careporter_id=408,331,130,765,320 } load_eligibility_plist: Failed to open //private/var/db/os_eligibility/eligibility.plist: Operation not permitted(1) - I verified and this file is indeed in non read mode on my Mac for the user. However it affects nothing. The following 2 pop up - although I have no explicit code or 3P code ( nor Ads) that require impressions - each time I click on the Game Center Access Point post authentication. Cannot add impressions because no tracker is specified by the metrics fields context. Did you forget to set one from your view controller or data source? Cannot add page fields because none are specified by the metrics fields context. Did you forget to add an PageMetricsPresenter to the object graph used for actions?
10
2
3.2k
Jun ’25
Best Practices for Logging and Error Reporting in macOS Daemon Applications
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.
1
0
181
May ’25
Storing logs from application written in Swift visible on real device
I folks, I have an application that is already available in production and I would like to store some logs to the app, so that on real device I will see outputs for better tracing. iOS13 would be fine, but I can migrate it into e.g. iOS 14. The next question is where to find logs on real devices, so that users can send me for tracing. Thanks Petr
1
0
158
Apr ’25
OSLogStore can't access an app's extensions?
I've got an iOS app with lots of extensions, some of them complex and doing a lot of stuff. After a bug I'd like to be able to use OSLogStore to get a holistic picture of logging for the app and its extensions and send that to a debugging server to retrospectively view logs for the app and its extensions. The constructor is OSLogStore.init(scope: OSLogStore.Scope), however scope only has one value .currentProcessIdentifier. Implying if that is called from within the app it can only get access to logging for its process only. I tried it out to confirm this is the case - if I log something in an extension (using Logger), then run the app with code like this:  let logStore = try! OSLogStore(scope: .currentProcessIdentifier)  let oneHourAgo = logStore.position(date: Date().addingTimeInterval(-3600)) let allEntries = try! logStore.getEntries(at: oneHourAgo)       for entry in allEntries { look at the content of the entry Then none of the entries are from the extension. Is there anyway from within the app I can access logging made within an extension?
4
0
927
Apr ’25
Private data is still hidden in the logs with System-wide Enable-Private-Data
I have installed the following configuration profile: <?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>PayloadContent</key> <array> <dict> <key>PayloadDisplayName</key> <string>Enable Private Data Logging for Unified Logging</string> <key>PayloadEnabled</key> <true/> <key>PayloadIdentifier</key> <string>com.apple.system.logging.2BFB8109-8829-4020-AEB7-BA21761AE50C</string> <key>PayloadType</key> <string>com.apple.system.logging</string> <key>PayloadUUID</key> <string>2BFB8109-8829-4020-AEB7-BA21761AE50C</string> <key>PayloadVersion</key> <integer>1</integer> <key>System</key> <dict> <key>Enable-Private-Data</key> <true/> </dict> </dict> </array> <key>PayloadDisplayName</key> <string>Enable Private Logging Data</string> <key>PayloadIdentifier</key> <string>Kentzo-Macbook.D000DF5D-AE7A-4D22-B1DC-8F9CD71A2DD2</string> <key>PayloadRemovalDisallowed</key> <false/> <key>PayloadType</key> <string>Configuration</string> <key>PayloadUUID</key> <string>1CF75441-D3C2-4E5B-B36A-394C397E8529</string> <key>PayloadVersion</key> <integer>1</integer> <key>ConsentText</key> <dict> <key>default</key> <string>Warning: Installing this profile will enable private data logging for all of unified logging.</string> </dict> </dict> </plist> But both Console.app and log show values like <mask.hash: 'Z9xIxlLTn0KlWPUjmpOSkg=='> for the com.apple.mDNSResponder subsystem. What do I need to do to reveal this information?
6
0
228
Apr ’25
Breakpoint on Runtime Issue os_log_fault_default_callback
The app stops on the breakpoint when "All Runtime Issues" is added. If I disable the breakpoint, the app runs normally. Is there a new project setting to avoid this breakpoint from being set. It does not appear to be a valid error. I am running Xcode 16.2. I edited the "Type" field in the breakpoint box. This occurs with the "System Frameworks" option only.
0
2
209
Apr ’25
What is the point of the Unified Logging System and the new `Logger` API if it's so inflexible and clumsy?
Hi there! Sorry in advance, this is going to be a long post of Apple developer pains which I want to share with you, and, hopefully, find the answer and help Apple become better. I'm at the very beginning of my new and exciting personal project which (I hope) may one day feed me and be my daily source of inspiration. I'm not a newbie in Apple development nor am I a senior-level developer — just a fellow developa'. Here's the problem I bring to you — why Apple promotes Unified Logging System and recommends using it as the primary way to implement logging in 3rd-party apps? No doubt, OSLog is a great, secure, efficient, and centralized way to gather diagnostics information, and I, starting my new project, am itching to choose exactly this 1st-party logging infrastructure. This decision in theory has a number of benefits: I don't have to depend on 3rd-party logging frameworks which may eventually be discontinued; I have extensive documentation, great WWDC sessions explaining how to use the framework, and stackoverflow answers from the whole Apple dev community in case I experience any troubles; I have this cool Console.app and upcoming Xcode 15 tools with great visualization and filtering of my logs; It's quite a robust and stable infrastructure which I may restfully rely on. But... the thing is there's this big elephant in the room — this API is non-customizable, inconvenient, and hard to use in terms of the app architecture. I can't write my own protocol wrapper around it to abstract my domain logic from implementation details or just simplify the usage at the call site. I can't configure my own format for log messages (this is debatable, since Console.app doesn't provide "naked strings" as Xcode 14 and earlier, but still). And what's most important — I can't conveniently retrieve the logs! I can't implement the functionality where my user just taps the button, and the logs are sent on the background queue to my support email (eskimo's answer). They would have to go through this monstrous procedure of holding volume buttons on the iPhone, connecting their device to the Mac, gathering sysdiagnose, entering some weird Terminal commands (jeez, these nerdy developers...), etc. If it ever succeeds, of course, and something doesn't go wrong, leaving my user angry and dissatisfied with my app. Regarding the protocol wrapper, I can't do something like this: protocol Logging { var logger: Logger { get } func info(_ message: OSLogMessage) } extension Logging { var logger: Logger { return Logger( subsystem: "com.my.bundle.id", category: String(describing: Self.self) ) } func info(_ message: OSLogMessage) { logger.info(message) } } class MyClass: Logging { func someImportantMethod() { // ... self.info("Some useful debug info: \(someVar, privacy: .public)") } } I've been investigating this topic for 2 days, and it's the farthest I want to go in beating my head over how to do two simple things: How to isolate logging framework implementation decision from my main code and write convenience wrappers? How to easily transfer the log files from the user to the developer? And I'm not the only one struggling. Here's just one example among hundreds of other questions that are being asked on dev forums: https://www.hackingwithswift.com/forums/ios/unified-logging-system-retrieve-logs-on-device/838. I've read almost all Apple docs which describe the modern Unified Logging System, I've read through eskimo's thread on Apple Developer Forum about the API, but I still haven't found the answer. Maybe, I've misperceived this framework and it's not the tool I'm searching for? Maybe, it focuses on different aspects of logging, e.g. signposting, rather than logging the current state of the app? What am I missing?
5
0
3.3k
Apr ’25
On Log Noise - Debugging
I came across several "errors" being reported when I run my app, however my app seems to function correctly. I believe they fall in the category listed on this ( now locked ) thread https://developer.apple.com/forums/thread/115461 However, I wanted to post the ones I found to clarify ( close to submission) just in case any of these end up being more than just log noise later. PLEASE let me know if you've come across these before and whether they impacted anything or if you can confirm they are just log noise. Thanks in advance! -[RTIInputSystemClient remoteTextInputSessionWithID:performInputOperation:] perform input operation requires a valid sessionID. inputModality = Keyboard, inputOperation = , customInfoType = UIEmojiSearchOperations AVAudioSession_iOS.mm:2,223 Server returned an error from destroySession:. Error Domain=NSCocoaErrorDomain Code=4099 “The connection to service with pid 102 named com.apple.audio.AudioSession was invalidated from this process.” UserInfo={NSDebugDescription=The connection to service with pid 102 named com.apple.audio.AudioSession was invalidated from this process. CAReportingClient.mm:532 Attempted to remove a reporter not created by this client { careporter_id=408,331,130,765,320 } load_eligibility_plist: Failed to open //private/var/db/os_eligibility/eligibility.plist: Operation not permitted(1) - I verified and this file is indeed in non read mode on my Mac for the user. However it affects nothing. The following 2 pop up - although I have no explicit code or 3P code ( nor Ads) that require impressions - each time I click on the Game Center Access Point post authentication. Cannot add impressions because no tracker is specified by the metrics fields context. Did you forget to set one from your view controller or data source? Cannot add page fields because none are specified by the metrics fields context. Did you forget to add an PageMetricsPresenter to the object graph used for actions?
Replies
10
Boosts
2
Views
3.2k
Activity
Jun ’25
Best Practices for Logging and Error Reporting in macOS Daemon Applications
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.
Replies
1
Boosts
0
Views
181
Activity
May ’25
Storing logs from application written in Swift visible on real device
I folks, I have an application that is already available in production and I would like to store some logs to the app, so that on real device I will see outputs for better tracing. iOS13 would be fine, but I can migrate it into e.g. iOS 14. The next question is where to find logs on real devices, so that users can send me for tracing. Thanks Petr
Replies
1
Boosts
0
Views
158
Activity
Apr ’25
OSLogStore can't access an app's extensions?
I've got an iOS app with lots of extensions, some of them complex and doing a lot of stuff. After a bug I'd like to be able to use OSLogStore to get a holistic picture of logging for the app and its extensions and send that to a debugging server to retrospectively view logs for the app and its extensions. The constructor is OSLogStore.init(scope: OSLogStore.Scope), however scope only has one value .currentProcessIdentifier. Implying if that is called from within the app it can only get access to logging for its process only. I tried it out to confirm this is the case - if I log something in an extension (using Logger), then run the app with code like this:  let logStore = try! OSLogStore(scope: .currentProcessIdentifier)  let oneHourAgo = logStore.position(date: Date().addingTimeInterval(-3600)) let allEntries = try! logStore.getEntries(at: oneHourAgo)       for entry in allEntries { look at the content of the entry Then none of the entries are from the extension. Is there anyway from within the app I can access logging made within an extension?
Replies
4
Boosts
0
Views
927
Activity
Apr ’25
Private data is still hidden in the logs with System-wide Enable-Private-Data
I have installed the following configuration profile: <?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>PayloadContent</key> <array> <dict> <key>PayloadDisplayName</key> <string>Enable Private Data Logging for Unified Logging</string> <key>PayloadEnabled</key> <true/> <key>PayloadIdentifier</key> <string>com.apple.system.logging.2BFB8109-8829-4020-AEB7-BA21761AE50C</string> <key>PayloadType</key> <string>com.apple.system.logging</string> <key>PayloadUUID</key> <string>2BFB8109-8829-4020-AEB7-BA21761AE50C</string> <key>PayloadVersion</key> <integer>1</integer> <key>System</key> <dict> <key>Enable-Private-Data</key> <true/> </dict> </dict> </array> <key>PayloadDisplayName</key> <string>Enable Private Logging Data</string> <key>PayloadIdentifier</key> <string>Kentzo-Macbook.D000DF5D-AE7A-4D22-B1DC-8F9CD71A2DD2</string> <key>PayloadRemovalDisallowed</key> <false/> <key>PayloadType</key> <string>Configuration</string> <key>PayloadUUID</key> <string>1CF75441-D3C2-4E5B-B36A-394C397E8529</string> <key>PayloadVersion</key> <integer>1</integer> <key>ConsentText</key> <dict> <key>default</key> <string>Warning: Installing this profile will enable private data logging for all of unified logging.</string> </dict> </dict> </plist> But both Console.app and log show values like <mask.hash: 'Z9xIxlLTn0KlWPUjmpOSkg=='> for the com.apple.mDNSResponder subsystem. What do I need to do to reveal this information?
Replies
6
Boosts
0
Views
228
Activity
Apr ’25
Breakpoint on Runtime Issue os_log_fault_default_callback
The app stops on the breakpoint when "All Runtime Issues" is added. If I disable the breakpoint, the app runs normally. Is there a new project setting to avoid this breakpoint from being set. It does not appear to be a valid error. I am running Xcode 16.2. I edited the "Type" field in the breakpoint box. This occurs with the "System Frameworks" option only.
Replies
0
Boosts
2
Views
209
Activity
Apr ’25
What is the point of the Unified Logging System and the new `Logger` API if it's so inflexible and clumsy?
Hi there! Sorry in advance, this is going to be a long post of Apple developer pains which I want to share with you, and, hopefully, find the answer and help Apple become better. I'm at the very beginning of my new and exciting personal project which (I hope) may one day feed me and be my daily source of inspiration. I'm not a newbie in Apple development nor am I a senior-level developer — just a fellow developa'. Here's the problem I bring to you — why Apple promotes Unified Logging System and recommends using it as the primary way to implement logging in 3rd-party apps? No doubt, OSLog is a great, secure, efficient, and centralized way to gather diagnostics information, and I, starting my new project, am itching to choose exactly this 1st-party logging infrastructure. This decision in theory has a number of benefits: I don't have to depend on 3rd-party logging frameworks which may eventually be discontinued; I have extensive documentation, great WWDC sessions explaining how to use the framework, and stackoverflow answers from the whole Apple dev community in case I experience any troubles; I have this cool Console.app and upcoming Xcode 15 tools with great visualization and filtering of my logs; It's quite a robust and stable infrastructure which I may restfully rely on. But... the thing is there's this big elephant in the room — this API is non-customizable, inconvenient, and hard to use in terms of the app architecture. I can't write my own protocol wrapper around it to abstract my domain logic from implementation details or just simplify the usage at the call site. I can't configure my own format for log messages (this is debatable, since Console.app doesn't provide "naked strings" as Xcode 14 and earlier, but still). And what's most important — I can't conveniently retrieve the logs! I can't implement the functionality where my user just taps the button, and the logs are sent on the background queue to my support email (eskimo's answer). They would have to go through this monstrous procedure of holding volume buttons on the iPhone, connecting their device to the Mac, gathering sysdiagnose, entering some weird Terminal commands (jeez, these nerdy developers...), etc. If it ever succeeds, of course, and something doesn't go wrong, leaving my user angry and dissatisfied with my app. Regarding the protocol wrapper, I can't do something like this: protocol Logging { var logger: Logger { get } func info(_ message: OSLogMessage) } extension Logging { var logger: Logger { return Logger( subsystem: "com.my.bundle.id", category: String(describing: Self.self) ) } func info(_ message: OSLogMessage) { logger.info(message) } } class MyClass: Logging { func someImportantMethod() { // ... self.info("Some useful debug info: \(someVar, privacy: .public)") } } I've been investigating this topic for 2 days, and it's the farthest I want to go in beating my head over how to do two simple things: How to isolate logging framework implementation decision from my main code and write convenience wrappers? How to easily transfer the log files from the user to the developer? And I'm not the only one struggling. Here's just one example among hundreds of other questions that are being asked on dev forums: https://www.hackingwithswift.com/forums/ios/unified-logging-system-retrieve-logs-on-device/838. I've read almost all Apple docs which describe the modern Unified Logging System, I've read through eskimo's thread on Apple Developer Forum about the API, but I still haven't found the answer. Maybe, I've misperceived this framework and it's not the tool I'm searching for? Maybe, it focuses on different aspects of logging, e.g. signposting, rather than logging the current state of the app? What am I missing?
Replies
5
Boosts
0
Views
3.3k
Activity
Apr ’25