I notice that Swift Data type's hashValue collision when first 80 byte of data and data length are same because of the Implementation only use first 80 bytes to compute the hash.
https://web.archive.org/web/20120605052030/https://opensource.apple.com/source/CF/CF-635.21/CFData.c
also, even if hash collision on the situation like this, I can check data is really equal or not by ==
does there any reason for this implementation(only use 80 byte of data to make hashValue)?
test code is under below
let dataArray: [UInt8] = [
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00
]
var dataArray1: [UInt8] = dataArray
var dataArray2: [UInt8] = dataArray
dataArray1.append(contentsOf: [0x00, 0x00, 0x00, 0x00])
dataArray2.append(contentsOf: [0xff, 0xff, 0xff, 0xff])
let data1 = Data(dataArray1)
let data2 = Data(dataArray2) // Only last 4 byte differs
print(data1.hashValue)
print(data2.hashValue)
print(data1.hashValue == data2.hashValue) // true
print(data1 == data2) // false
Foundation
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This crash report for one of my apps was downloaded by Xcode. Apparently the app crashed while releasing an object of type Scan.File, which is a Swift class held in an array in the Scan.Directory class. I'm not doing any manual reference counting or low-level stuff with that object.
What could cause such a crash?
crash.crash
I'm simply trying to use a proxy to route a http request in Swift to measure the average round trip time of a list of proxies. I've went through multiple Stack Overflow threads on this topic but they are all super old / outdated.
format:host:port:username:password
I also added the info.plist entry:
NSAllowsArbitraryLoads -> NSExceptionDomains
When I call the function below I am prompted with a menu that says
"Proxy authentication required. Enter the password for HTTP proxy ... in settings"
I closed this menu inside my app and tried the function below again and it worked without giving me the menu a second time. However even though the function works without throwing any errors, it does NOT use the proxies to route the request.
Why does the request work (throws no errors) but does not use the proxies? I'm assuming it's because the password isn't entered in the settings as the alert said. My users will want to test proxy speeds for many different Hosts/Ports, it doesn't make sense to enter the password in settings every time. How can I fix this issue?
func averageProxyGroupSpeed(proxies: [String], completion: @escaping (Int, String) -> Void) {
let numProxies = proxies.count
if numProxies == 0 {
completion(0, "No proxies")
return
}
var totalTime: Int64 = 0
var successCount = 0
let group = DispatchGroup()
let queue = DispatchQueue(label: "proxyQueue", attributes: .concurrent)
let lock = NSLock()
let shuffledProxies = proxies.shuffled()
let selectedProxies = Array(shuffledProxies.prefix(25))
for proxy in selectedProxies {
group.enter()
queue.async {
let proxyDetails = proxy.split(separator: ":").map(String.init)
guard proxyDetails.count == 4,
let port = Int(proxyDetails[1]),
let url = URL(string: "http://httpbin.org/get") else {
completion(0, "Invalid proxy format")
group.leave()
return
}
var request = URLRequest(url: url)
request.timeoutInterval = 15
let configuration = URLSessionConfiguration.default
configuration.connectionProxyDictionary = [
AnyHashable("HTTPEnable"): true,
AnyHashable("HTTPProxy"): proxyDetails[0],
AnyHashable("HTTPPort"): port,
AnyHashable("HTTPSEnable"): false,
AnyHashable("HTTPUser"): proxyDetails[2],
AnyHashable("HTTPPassword"): proxyDetails[3]
]
let session = URLSession(configuration: configuration)
let start = Date()
let task = session.dataTask(with: request) { _, _, error in
defer { group.leave() }
if let error = error {
print("Error: \(error.localizedDescription)")
} else {
let duration = Date().timeIntervalSince(start) * 1000
lock.lock()
totalTime += Int64(duration)
successCount += 1
lock.unlock()
}
}
task.resume()
}
}
group.notify(queue: DispatchQueue.main) {
if successCount == 0 {
completion(0, "Proxies Failed")
} else {
let averageTime = Int(Double(totalTime) / Double(successCount))
completion(averageTime, "")
}
}
}
I bought a Mac mini M4 and when I used it to sign up for a developer account, I was always encountered, it needed me to take a photo, but I didn't have a camera, so I used the iriun software to connect my phone to take a photo, it works fine in FaceTime, but when I take a photo in the Apple Developer app, the round photo frame is shown black.
How can I make the camera work and if I buy a third-party camera?
Is there a way to create a Date constant from year, month and day? The only constructors that show up are .now and those based on some timeInterval. I'm trying to initialize some test data with known dates.
After the app is put in background for sometime and brought in to foreground and the app crashes each time with a different thread stack entries but all of them states same exception reason.
Hello,
I'm trying to display some Duration in a live activity using a custom format, with the goal of displaying a match time (only minutes) as, e.g. 33', 45' (+2), etc.
For that purpose, I'm using a TimeDataSource<Duration>, so that it also updates automatically given a starting point.
I've implemented my custom FormatStyle, trying to somehow mimic the existing UnitsFormatStyle (which perfectly works with live activities) but just changing the format.
I've added conformance to DiscreteFormatStyle, and code-wise everything seems to be ok (if I've understood things correctly). It compiles and it even works as expected in a playground.
However, when trying to use it within the live activity, I'm getting these cryptic errors in the Console.app, and the live activity just turns into a view with placeholders
Failed to fetch view from archive at index 12: SwiftUI.AnyCodable<SwiftUI.(unknown context at $1d47f6af0).SafelyCodableRequirement>.(unknown context at $1d47fe410).Errors.noType(mangledName: "7SwiftUI18TimeDataFormattingO10ResolvableVy_AA0cD6SourceVAAE15DurationStorageOys0H0V_GAK28BlickLiveActivitiesExtensionE16MatchFormatStyleVG")
[624AEC37-13D9-4927-9F41-C3092B61E214] Failed to return view entry from archive for view model with tag listItem with error: SwiftUI.AnyCodable<SwiftUI.(unknown context at $1d47f6af0).SafelyCodableRequirement>.(unknown context at $1d47fe410).Errors.noType(mangledName: "7SwiftUI18TimeDataFormattingO10ResolvableVy_AA0cD6SourceVAAE15DurationStorageOys0H0V_GAK28BlickLiveActivitiesExtensionE16MatchFormatStyleVG")
Are there any limitations when it comes to live activities and these custom formatters? This whole error doesn't make sense, since I'm only aiming to update every minute, which should just be fine, the same thing I get with the UnitsFormatStyle.
For reference, this is my playground, which just works as expected:
import Foundation
import SwiftUI
import PlaygroundSupport
extension Duration {
struct MatchFormatStyle: DiscreteFormatStyle, Sendable {
let periodLength: Int
let overtime: Int
func format(_ value: Duration) -> String {
let (seconds, _): (Int64, Int64) = value.components
let minutes: Int = Int(seconds) / 60
let current: Int = periodLength + minutes + overtime
if current > periodLength {
return "\(periodLength)' (+\(current - periodLength))"
} else {
return "\(current)'"
}
}
func discreteInput(before input: Duration) -> Duration? {
let (seconds, _): (Int64, Int64) = input.components
let minutes: Int64 = seconds / 60 - 1
return Duration(secondsComponent: minutes * 60, attosecondsComponent: .zero)
}
func discreteInput(after input: Duration) -> Duration? {
let (seconds, _): (Int64, Int64) = input.components
let minutes: Int64 = seconds / 60 + 1
return Duration(secondsComponent: minutes * 60, attosecondsComponent: .zero)
}
}
}
extension FormatStyle where Self == Duration.MatchFormatStyle {
static func matchTime(currentTime: Int, periodLength: Int) -> Duration.MatchFormatStyle {
return Duration.MatchFormatStyle(periodLength: periodLength, overtime: max(currentTime - periodLength, .zero))
}
}
extension TimeDataSource<Date> {
static func matchDuration(for currentTime: Int, periodLength: Int) -> TimeDataSource<Duration> {
let minutesAhead: Double = Double(max(periodLength - currentTime + 1, .zero))
return TimeDataSource<Date>.durationOffset(to: Date.now.addingTimeInterval(minutesAhead * 60))
}
}
struct FooView: View {
let currentTime: Int = 36
let periodLength: Int = 45
var body: some View {
Text(
TimeDataSource<Date>.matchDuration(for: currentTime, periodLength: periodLength),
format: .matchTime(currentTime: currentTime, periodLength: periodLength)
)
.frame(width: 400, height: 200)
.font(.system(size: 50))
}
}
// Present the view controller in the Live View window
PlaygroundPage.current.setLiveView(FooView())
Any hints or suggestions are welcome, many thanks in advance.
On macOS, the Finder allows to connect to a server and store the login credentials. When creating a bookmark to a file on a server and resolving it again, the server is mounted automatically (unless I provide the option URL.BookmarkResolutionOptions.withoutMounting).
I just tried connecting to my Mac from my iPad via SMB in the Files app and storing a bookmark to a file on the server, but disconnecting the server and trying to resolve the bookmark throws the error (I translated the English text from Italian):
Error Domain=NSFileProviderErrorDomain Code=-2001 "No file provider was found with the identifier "com.apple.SMBClientProvider.FileProvider"'" UserInfo={NSLocalizedDescription=No file provider was found with the identifier "com.apple.SMBClientProvider.FileProvider"., NSUnderlyingError=0x302a1a340 {Error Domain=NSFileProviderErrorDomain Code=-2013 "(null) "}}
Every time I disconnect and reconnect to the server, selecting the same file returns a different path. The first time I got
/private/var/mobile/Library/LiveFiles/com.apple.filesystems.smbclientd/WtFD3Ausername/path/to/file.txt
The next time WtFD3A changed to EqHc2g and so on.
Is it not possible to automatically mount a server when resolving a bookmark on iOS?
The following code allows to reproduce the issue:
struct ContentView: View {
@State private var isPresentingFilePicker = false
@AppStorage("bookmarkData") private var bookmarkData: Data?
@State private var url: URL?
@State private var stale = false
@State private var error: Error?
var body: some View {
VStack {
Button("Open") {
isPresentingFilePicker = true
}
if let url = url {
Text(url.path)
} else if bookmarkData != nil {
Text("couldn't resolve bookmark data")
} else {
Text("no bookmark data")
}
if stale {
Text("bookmark is stale")
}
if let error = error {
Text("\(error)")
.foregroundStyle(.red)
}
}
.padding()
.fileImporter(isPresented: $isPresentingFilePicker, allowedContentTypes: [.data]) { result in
do {
let url = try result.get()
if url.startAccessingSecurityScopedResource() {
bookmarkData = try url.bookmarkData()
}
} catch {
self.error = error
}
}
.onChange(of: bookmarkData, initial: true) { _, bookmarkData in
if let bookmarkData = bookmarkData {
do {
url = try URL(resolvingBookmarkData: bookmarkData, bookmarkDataIsStale: &stale)
} catch {
self.error = error
}
}
}
}
}
Hi all,
I use the FileManager trashIitem function to put a file in the trash.
If it is only one file, then the option to put it back is available.
If, however, several files are deleted, the option to put it back is only available for the first
deleted file. All others cannot be put back.
The problem has been known for at least 10 years.
See Put back only works for the first file.
NSWorkspace recycle has the same problem.
It seems to be due to .DS_Store in the trash. The files that are in the trash are stored there. This may also lead you to believe that the trashItem function is working properly because the deleted files are still in the .DS_Store file.
If I call trashItem or recycle several times and wait 2 seconds between calls, then the option to put it back is available for all of them.
That obviously can't be the solution. Waiting less than 2 seconds only offers to put the first file back.
So trashItem and recycle are the same as remove, with the difference that you can look at the files in the trash can again, but not put them back.
Are there other ways?
The Finder can also delete multiple files and put them all back.
On macOS, we have didMountNotification but there doesn't seem to be an equivalent for iOS. Is there a way to be notified when a volume is mounted on iOS? I would like to use it in my iOS app I'm currently porting from macOS, which starts a synchronization from the volume (which has been previously selected in a NSOpenPanel) as soon as it's mounted.
Some time ago I read somewhere that one can get a file icon on iOS like this:
UIDocumentInteractionController(url: url).icons.last!)
but this always returns the following image for every file:
Today I tried the following, which always returns nil:
(try? url.resourceValues(forKeys: [.effectiveIconKey]))?.allValues[.effectiveIconKey] as? UIImage
Is there any way to get a file icon on iOS?
You can try the above methods in this sample app:
struct ContentView: View {
@State private var isPresentingFilePicker = false
@State private var url: URL?
var body: some View {
VStack {
Button("Open") {
isPresentingFilePicker = true
}
if let url = url {
Image(uiImage: UIDocumentInteractionController(url: url).icons.last!)
if let image = (try? url.resourceValues(forKeys: [.effectiveIconKey]))?.allValues[.effectiveIconKey] as? UIImage {
Image(uiImage: image)
} else {
Text("none")
}
}
}
.padding()
.fileImporter(isPresented: $isPresentingFilePicker, allowedContentTypes: [.data]) { result in
do {
let url = try result.get()
if url.startAccessingSecurityScopedResource() {
self.url = url
}
} catch {
preconditionFailure(error.localizedDescription)
}
}
}
}
We use URLSessionWebSocketTask for web socket connection. When get error we reconnect - recreate new URLSessionWebSocketTask.
Test case: off wifi on iOS device; get error(s) URLError.notConnectedToInternet. When on wifi correct create new task with connect.
This working on iOS 12, 14, 15, 16, 17. But on iOS 18 we get error URLError.notConnectedToInternet without correct connection.
class WebSocketManager {
...
func openConnection() {
webSocketTask?.cancel(with: .goingAway, reason: nil)
webSocketTask = urlSession?.webSocketTask(with: urlRequest)
webSocketTask?.resume()
listen()
}
func closeConnection() {
webSocketTask?.cancel(with: .goingAway, reason: nil)
webSocketTask = nil
}
private func listen() {
webSocketTask?.receive { [weak self] result in
guard let self else { return }
switch result {
case .failure(let error):
delegate?.webSocketManager(self, error: error)
case .success(let message):
switch message {
case .string(let text):
delegate?.webSocketManager(self, message: .text(text))
case .data(let data):
delegate?.webSocketManager(self, message: .data(data))
@unknown default:
fatalError()
}
listen()
}
}
}
}
Delegate:
func webSocketManager(_ webSocketManager: WebSocketManagerType, error: Error) {
webSocketManager.openConnection()
}
The following code works when compiling for macOS:
print(NSMutableDictionary().isEqual(to: NSMutableDictionary()))
but produces a compiler error when compiling for iOS:
'NSMutableDictionary' is not convertible to '[AnyHashable : Any]'
NSDictionary.isEqual(to:) has the same signature on macOS and iOS. Why does this happen? Can I use NSDictionary.isEqual(_:) instead?
I recently noticed an inconsistency in how languages are represented in Apple’s new Translation API compared to Foundation’s Locale system.
Observation from the Translation API
When retrieving the list of supported languages using:
let availableLanguages = try await LanguageAvailability().supportedLanguages
The results are:
Language(components: Foundation.Locale.Language.Components(languageCode: Optional(uk), script: nil, region: Optional(UA)))
Language(components: Foundation.Locale.Language.Components(languageCode: Optional(zh), script: nil, region: Optional(TW)))
Language(components: Foundation.Locale.Language.Components(languageCode: Optional(ko), script: nil, region: Optional(KR)))
Language(components: Foundation.Locale.Language.Components(languageCode: Optional(en), script: nil, region: Optional(GB)))
Language(components: Foundation.Locale.Language.Components(languageCode: Optional(de), script: nil, region: Optional(DE)))
Language(components: Foundation.Locale.Language.Components(languageCode: Optional(zh), script: nil, region: Optional(CN)))
Language(components: Foundation.Locale.Language.Components(languageCode: Optional(ja), script: nil, region: Optional(JP)))
Language(components: Foundation.Locale.Language.Components(languageCode: Optional(id), script: nil, region: Optional(ID)))
Language(components: Foundation.Locale.Language.Components(languageCode: Optional(nl), script: nil, region: Optional(NL)))
....
Key points:
• The script component is always nil.
• Region codes (CN, TW, etc.) determine the script for languages like Chinese (Simplified or Traditional).
• Other languages (e.g., en-GB, en-US, pt-BR) also rely on region-based identification.
Observation from Foundation Locale (Locale.current.language)
When retrieving the user’s system language setting:
systemLanguageObj = Locale.current.language
I get a different format where the script component is present, but the region may vary based on user settings. This means that mapping between script and region is not consistent between the two APIs, requiring manual handling.
My key questions:
1. Is my current approach correct, or is there a better way to get user language settings that match Translation API identifiers?
2. If no alternative exists, could the Translation API align its language identification method with Foundation Locale to reduce ambiguity?
Any insights or suggestions would be greatly appreciated!
After the app is put in background for sometime and the app crashes,
Some cases have the webView involvement before putting the app in to background for quite sometime and pulled into foreground.
Here's the crash log information.
Identifier: com.app.myapp
Version: 2.3.3 (30)
AppStoreTools: 16C5031b
AppVariant: 1:iPhone9,1:15
Code Type: ARM-64 (Native)
Role: Foreground
Parent Process: launchd [1]
Coalition: com.app.myapp [2833]
Date/Time: 2024-12-12 17:30:57.4489 +0100
Launch Time: 2024-12-12 17:04:19.7290 +0100
OS Version: iPhone OS 15.5 (19F77)
Release Type: User
Baseband Version: 9.61.00
Report Version: 104
**Exception Type: EXC_BREAKPOINT (SIGTRAP)
Exception Codes: 0x0000000000000001, 0x000000018f1358e0
Exception Note: EXC_CORPSE_NOTIFY
Termination Reason: SIGNAL 5 Trace/BPT trap: 5
Terminating Process: exc handler [82527]
Triggered by Thread: 10
Kernel Triage:
VM - Fault hit memory shortage**
Thread 10 Crashed:
0 WebKit 0x000000018f1358e0 WTFCrashWithInfo(int, char const*, char const*, int) + 20 (Assertions.h:732)
1 WebKit 0x000000018f72e348 WebKit::allDataStores() + 72 (WebsiteDataStore.cpp:100)
2 WebKit 0x000000018f72e278 WebKit::WebsiteDataStore::forEachWebsiteDataStore(WTF::Function<void (WebKit::WebsiteDataStore&)>&&) + 24 (WebsiteDataStore.cpp:107)
3 WebKit 0x000000018f67c440 WebKit::WebProcessPool::updateProcessAssertions() + 52 (WebProcessPool.cpp:1773)
4 WebKit 0x000000018f684508 WebKit::WebProcessProxy::didSetAssertionType(WebKit::ProcessAssertionType) + 880 (Function.h:82)
5 WebKit 0x000000018f5bfdd0 WebKit::ProcessThrottler::setAssertionType(WebKit::ProcessAssertionType) + 712 (ProcessThrottler.cpp:148)
6 WebKit 0x000000018f5bf9b4 WebKit::ProcessThrottler::updateAssertionIfNeeded() + 408 (ProcessThrottler.cpp:176)
7 WebKit 0x000000018f5c42b0 WebKit::ProcessThrottler::Activity<(WebKit::ProcessThrottler::ActivityType)1>::Activity(WebKit::ProcessThrottler&, WTF::ASCIILiteral) + 76 (ProcessThrottler.cpp:58)
8 WebKit 0x000000018f659958 WebKit::WebPageProxy::runJavaScriptInFrameInScriptWorld(WebCore::RunJavaScriptParameters&&, std::__1::optional<WTF::ObjectIdentifierWebCore::FrameIdentifierType >, API::ContentWorld&, WTF::Comple... + 240 (ProcessThrottler.h:66)
9 WebKit 0x000000018f3ca7cc -[WKWebView _evaluateJavaScript:asAsyncFunction:withSourceURL:withArguments:forceUserGesture:inFrame:inWorld:completionHandler:] + 1352 (WKWebView.mm:1151)
10 WebKit 0x000000018f131700 -[WKWebView evaluateJavaScript:completionHandler:] + 120 (WKWebView.mm:896)
11 MyApp 0x00000001044e7e64 cli_signalHandler + 2420
12 MyApp 0x00000001044e4470 getExtraInfoId + 132792
13 MyApp 0x00000001044c2b18 CLI_Reset + 50684
14 MyApp 0x00000001044c2a18 CLI_Reset + 50428
15 MyApp 0x00000001044c1cec CLI_Reset + 47056
16 MyApp 0x00000001044c27e8 CLI_Reset + 49868
17 MyApp 0x00000001044e01f4 getExtraInfoId + 115772
18 MyApp 0x0000000104492498 StringToScreenDensityLevel + 4588
19 libdispatch.dylib 0x0000000180e80094 _dispatch_client_callout + 16 (object.m:560)
20 libdispatch.dylib 0x0000000180e22bb8 _dispatch_continuation_pop$VARIANT$mp + 440 (inline_internal.h:2622)
21 libdispatch.dylib 0x0000000180e348dc _dispatch_source_invoke$VARIANT$mp + 1668 (source.c:596)
22 libdispatch.dylib 0x0000000180e22730 _dispatch_queue_override_invoke + 424 (queue.c:0)
23 libdispatch.dylib 0x0000000180e2fb94 _dispatch_root_queue_drain + 340 (inline_internal.h:0)
24 libdispatch.dylib 0x0000000180e3039c _dispatch_worker_thread2 + 172 (queue.c:6935)
25 libsystem_pthread.dylib 0x00000001dc483dd4 _pthread_wqthread + 224 (pthread.c:2612)
26 libsystem_pthread.dylib 0x00000001dc48393c start_wqthread + 8 (:-1)
Thread 10 crashed with ARM Thread State (64-bit):
x0: 0x0000000000000064 x1: 0x000000018fad60a0 x2: 0x000000018fad6189 x3: 0x0000000000000113
x4: 0x0000000000000030 x5: 0x0000000100000030 x6: 0x0000000000000000 x7: 0x0000000000000001
x8: 0x000000016fd6b000 x9: 0x0000000106dd4580 x10: 0x000000000000002c x11: 0x0000000000020408
x12: 0x0000000000080000 x13: 0x0000000000000000 x14: 0x0000020000011000 x15: 0x0000000100000000
x16: 0x00000001dc48425c x17: 0x0000000000000000 x18: 0x0000000000000000 x19: 0x000000016fd6a418
x20: 0x0000000282ece080 x21: 0x00000002834ac2a0 x22: 0x00000001f694c000 x23: 0x0000000117004a80
x24: 0x0000000283bb6558 x25: 0x000000011a00a1d8 x26: 0x0000000000000000 x27: 0x0000000000000002
x28: 0x000000016fd6b180 fp: 0x000000016fd6a3d0 lr: 0x000000018f72e348
sp: 0x000000016fd6a3b0 pc: 0x000000018f1358e0 cpsr: 0x60000000
esr: 0xf200c471 (Breakpoint) pointer authentication trap IB
When my app launches, it makes maybe 9 or so network requests to load initial data. It also reads some data from disc.
Sporadically, I'm seeing an issue where some of the network requests succeed, but anything involving reading from disc does not load immediately. I'm able to move around in the app, tap buttons, swap tabs, swipe pages, so my main actor isn't stuck. Other data that don't involve disc reading / writing is also blank. About 2 minutes in, suddenly everything loads (both stuff from disc and stuff from the network), nearly instantly, the way it should have done when the app launched.
Server logs show more initial network requests succeed than we can see data loaded in the app, and then about 2 minutes later, there's a flood of the rest of the requests which then succeed.
The responses to some of these initial network requests cause us to make other network requests, and the sever sees some of those start right away.
However, other consequences of these first requests are to touch the disc (to search for manually-cached data), and anything that is supposed to happen after that does not succeed until the 2 minute mark.
But what bothers me is some things in the app which don't touch the disc also seem to have successful network requests.
I'm seeing it on an iPhone 14Pro running iOS 18.2.1, with 607 GB of disc space available.
When I take screenshots of the loading screens in my app during the apparent freeze, the clock in the screenshots are right - they reflect the clock at the moment I took the screenshot, but the EXIF data in all dozen or so images shows the exact second 2 minutes later when the server gets the resulting flood of network requests. Screenshots taken after the freeze is over have exif timestamps that match the screenshots, as short as 5 seconds after the freeze ends. The screenshot file names, though sequential, are out of order. for instance, some screenshots from 12:58 have file names numbered after screenshots taken at 12:59. but not all are out of order.
This seems like disc contention has spread outside the app, and is impacting the system writing the images to disc.
How do I diagnose a cause for this? How does disc contention affect the networking? I have caching turned off for my network requests. We only have a manual image cache, but I don't know how that would stall the display of data that should fetch and display without attempting to hit the image cache.
This happens maybe a couple of times a day for some people, maybe once every couple of weeks for others, but of course, it never when we're trying to debug it.
Hi there
The behaviour of using Locale(identifier: "ar") with NumberFormatter.locale appears to have changed between iOS 17 and iOS 18.
Is this expected?
Steps to reproduce
import UIKit
func numberFormatter(withlocaleString localeString: String) -&gt; NumberFormatter {
let locale = Locale(identifier: localeString)
let numberFormatter = NumberFormatter()
numberFormatter.locale = locale
return numberFormatter
}
let numbers = 0...9
let localeDigits = numbers
let ar_digits = localeDigits.compactMap {
numberFormatter(withlocaleString: "ar").string(for: $0)?.first
}
print(ar_digits)
Results
The results show:
**** numbering system on iOS 17
latn numbering system on iOS 18.
iOS
Output
iOS 17
["٠", "١", "٢", "٣", "٤", "٥", "٦", "٧", "٨", "٩"]
iOS 18
["0", "1", "2", "3", "4", "5", "6", "7", "8", "9"]
Hello everyone,
There is one thing about Objective-C's memory management that confuses me, which is a returned object's lifetime from methods with names doesn't start with "alloc", "new", "copy", or "mutableCopy".
Take this as an example, when using NSBitmapImageRep's representationUsingType:properties: method, it returns an NSData object (reference: https://developer.apple.com/documentation/appkit/nsbitmapimagerep/representation(using:properties:)?language=objc).
While testing this out, the NSData seemed to be an owned object (it doesn't get released until the end of the program).
From what I understand, this may be an auto-released object which is released at the end of an autorelease pool block.
Could someone explain this in more detail? What if I want to release that NSData object before the end of the autorelease pool block? How can I know which object is autoreleased, borrowed, or owned?
I've noticed that NSTaks has this property as of macOS 14.4
@property (nullable, copy) NSData *launchRequirementData API_AVAILABLE(macos(14.4)) API_UNAVAILABLE(ios, watchos, tvos, visionos);
It has no documentation whatsoever. Even google search has no clue. Does this have anything to do with code signature requirements validation? Any explanations and examples would be appreciated!
In iOS 18, we encountered a crash:
Thread 4 name: com.apple.root.user-interactive-qos
Thread 4 Crashed:
0 CoreFoundation 0x18c4f9b10 __CFCheckCFInfoPACSignature + 4
1 CoreFoundation 0x18c53ed64 CFBundleGetInfoDictionary + 24
2 CoreFoundation 0x18c53ed1c CFBundleGetIdentifier + 16
3 Foundation 0x18b153740 -[NSUserDefaults(NSUserDefaults) _initWithSuiteName:container:] + 84
4 UIKitCore 0x18ef26ef0 ___UIKitUserDefaults_block_invoke + 40
5 libdispatch.dylib 0x1941ee0d0 _dispatch_client_callout + 20
6 libdispatch.dylib 0x1941ef918 _dispatch_once_callout + 32
7 UIKitCore 0x18ef9de28 _UIKitUserDefaults + 80
8 UIKitCore 0x18f058a7c ___UIKitPreferencesOnce_block_invoke + 20
9 libdispatch.dylib 0x1941ee0d0 _dispatch_client_callout + 20
10 libdispatch.dylib 0x1941ef918 _dispatch_once_callout + 32
11 UIKitCore 0x18f056c8c _UIKitPreferencesOnce + 80
12 UIKitCore 0x18f0563b8 ___UIApplicationMainPreparations_block_invoke + 20
13 libdispatch.dylib 0x1941ec370 _dispatch_call_block_and_release + 32
14 libdispatch.dylib 0x1941ee0d0 _dispatch_client_callout + 20
15 libdispatch.dylib 0x1941fff60 _dispatch_root_queue_drain + 860
16 libdispatch.dylib 0x194200590 _dispatch_worker_thread2 + 156
17 libsystem_pthread.dylib 0x2136ffc40 _pthread_wqthread + 228
18 libsystem_pthread.dylib 0x2136fc488 start_wqthread + 8
Below image show more details:
And after set a symbol breakpoint:
[NSUserDefaults _initWithSuiteName:container:]
We found that at the beginning of app launch, the system will call it:
It not always crash, but sometimes especially when app upgrade, what the root cause maybe?