File retrieval from storage location makes the app crash on iPadOS

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#1

I’m having constant crash on my device running iPadOS. The crash didn’t trigger on simulator but on physical device only.

I was trying to save a file to File.applicationStorageDirectory and later retrieve. While writing - the app does not complaint, but while retrieving the file, the app crash.

Here’s the code that I’m using to write file:

var fs:FileStream = new FileStream();
fs.open(
      File.applicationStorageDirectory.resolvePath("settings" + File.separator +"preferences.txt"), 
      FileMode.WRITE);
fs.writeUTFBytes(cast(data, String));
fs.close();

Next, I tries to retrieve the file:

var fl = File.applicationStorageDirectory.resolvePath("settings" + File.separator +"preferences.txt");        
if (fl.exists)
{
        var fs:FileStream = new FileStream();
        fs.addEventListener(ProgressEvent.PROGRESS, onOutputProgress);
        fs.addEventListener(IOErrorEvent.IO_ERROR, onIOErrorReadChannel);
        fs.addEventListener(Event.COMPLETE, onFileReadCompletes);
        fl.canonicalize();
        fs.openAsync(target, FileMode.READ);
}

Unfortunately, crash doesn’t provide much of an information but this:

Thread 0 name:
Thread 0 Crashed:
0 libsystem_kernel.dylib 0x00000001ef1c7198 __pthread_kill + 8 (:-1)
1 libsystem_pthread.dylib 0x00000001fe69a5f8 pthread_kill + 208 (pthread.c:1670)
2 libsystem_c.dylib 0x00000001bb0c84b8 abort + 124 (abort.c:118)
3 libc++abi.dylib 0x00000001fe5d2f54 abort_message + 128 (:-1)
4 libc++abi.dylib 0x00000001fe5c3a4c demangling_terminate_handler() + 300 (:-1)
5 libobjc.A.dylib 0x00000001ad5bab0c _objc_terminate() + 140 (objc-exception.mm:501)
6 libc++abi.dylib 0x00000001fe5d2424 std::__terminate(void (*)()) + 12 (:-1)
7 libc++abi.dylib 0x00000001fe5d4f90 __cxa_rethrow + 144 (:-1)
8 libobjc.A.dylib 0x00000001ad5b70fc objc_exception_rethrow + 40 (objc-exception.mm:401)
9 CoreFoundation 0x00000001b42d1de4 CFRunLoopRunSpecific + 780 (CFRunLoop.c:3434)
10 GraphicsServices 0x00000001ebae5998 GSEventRunModal + 160 (GSEvent.c:2196)
11 UIKitCore 0x00000001b656434c -[UIApplication _run] + 868 (UIApplication.m:3782)
12 UIKitCore 0x00000001b6563fc4 UIApplicationMain + 312 (UIApplication.m:5372)
13 GBAuth3 0x0000000101250f80 0x100f68000 + 3051392
14 dyld 0x00000001d1a80344 start + 1860 (dyldMain.cpp:1165)

#2

I think I found the culprit (in my codes):
fl.canonicalize();

Once this removed to run on iOS, the app stops to crash. I rather run the command on desktop only now,

#if desktop
fl.canonicalize();
#end

The problem seems to have fixed now. Sorry, for the noise. )

1 Like
#3

Interesting, I wonder if the internal FileSystem.readDirectory() call is throwing an exception on iOS.