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iphoneiosipadnsfilemanagerdiskspace
Code.Decode
Code.Decode

Reputation: 3804

How to detect total available/free disk space on the iPhone/iPad device?

I'm looking for a better way to detect available/free disk space on the iPhone/iPad device programmatically.
Currently I'm using the NSFileManager to detect the disk space. Following is the snippet of the code which does the job for me:

-(unsigned)getFreeDiskspacePrivate {
NSDictionary *atDict = [[NSFileManager defaultManager] attributesOfFileSystemForPath:@"/" error:NULL];
unsigned freeSpace = [[atDict objectForKey:NSFileSystemFreeSize] unsignedIntValue];
NSLog(@"%s - Free Diskspace: %u bytes - %u MiB", __PRETTY_FUNCTION__, freeSpace, (freeSpace/1024)/1024);

return freeSpace;
}


Am I correct with the above snippet? or is there any better way to know total available/free disk space.
I've to detect total free disk space, since we've to prevent our application to perform sync in the low disk space scenario.

Upvotes: 158

Views: 97435

Answers (19)

Nikaaner
Nikaaner

Reputation: 1320

I created such an extension. In most cases, it covers all needs. The path is specified correct for Apple File System.

extension FileManager {
    /// A value indicates the amount of free space on the file system in bytes.
    var systemFreeSize: Int64? {
        guard let attributes = try? FileManager.default.attributesOfFileSystem(forPath: "/") else { return nil }
        return attributes[.systemFreeSize] as? Int64
    }
}

Upvotes: 1

ivanzoid
ivanzoid

Reputation: 6062

Here is Swift 5 extension for FileManager with proper error handling and no automatic string conversions (convert byte count to string as you prefer). Also follows FileManager's naming.

extension FileManager {
    func systemFreeSizeBytes() -> Result<Int64, Error> {
        do {
            let attrs = try attributesOfFileSystem(forPath: NSHomeDirectory())
            guard let freeSize = attrs[.systemFreeSize] as? Int64 else {
                return .failure(NSError(domain: "", code: 0, userInfo: [NSLocalizedDescriptionKey : "Can't retrieve system free size"]))
            }
            return .success(freeSize)
        } catch {
            return .failure(error)
        }
    }

    func systemSizeBytes() -> Result<Int64, Error> {
         do {
             let attrs = try attributesOfFileSystem(forPath: NSHomeDirectory())
             guard let size = attrs[.systemSize] as? Int64 else {
                 return .failure(NSError(domain: "", code: 0, userInfo: [NSLocalizedDescriptionKey : "Can't retrieve system size"]))
             }
             return .success(size)
         } catch {
             return .failure(error)
         }
     }
}

Example usage:

let freeSizeResult = FileManager.default.systemFreeSizeBytes()
switch freeSizeResult {
case .failure(let error):
    print(error)
case .success(let freeSize):
    let freeSizeString = ByteCountFormatter.string(fromByteCount: freeSize, countStyle: .file)
    print("free size: \(freeSizeString)")
}

Upvotes: 7

Cuong Lam
Cuong Lam

Reputation: 3512

I have written a class to get available/used memory using Swift. Demo at: https://github.com/thanhcuong1990/swift-disk-status
Swift 4 updated.

import UIKit

class DiskStatus {

    //MARK: Formatter MB only
    class func MBFormatter(_ bytes: Int64) -> String {
        let formatter = ByteCountFormatter()
        formatter.allowedUnits = ByteCountFormatter.Units.useMB
        formatter.countStyle = ByteCountFormatter.CountStyle.decimal
        formatter.includesUnit = false
        return formatter.string(fromByteCount: bytes) as String
    }


    //MARK: Get String Value
    class var totalDiskSpace:String {
        get {
            return ByteCountFormatter.string(fromByteCount: totalDiskSpaceInBytes, countStyle: ByteCountFormatter.CountStyle.file)
        }
    }

    class var freeDiskSpace:String {
        get {
            return ByteCountFormatter.string(fromByteCount: freeDiskSpaceInBytes, countStyle: ByteCountFormatter.CountStyle.file)
        }
    }

    class var usedDiskSpace:String {
        get {
            return ByteCountFormatter.string(fromByteCount: usedDiskSpaceInBytes, countStyle: ByteCountFormatter.CountStyle.file)
        }
    }


    //MARK: Get raw value
    class var totalDiskSpaceInBytes:Int64 {
        get {
            do {
                let systemAttributes = try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory() as String)
                let space = (systemAttributes[FileAttributeKey.systemSize] as? NSNumber)?.int64Value
                return space!
            } catch {
                return 0
            }
        }
    }

    class var freeDiskSpaceInBytes:Int64 {
        get {
            do {
                let systemAttributes = try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory() as String)
                let freeSpace = (systemAttributes[FileAttributeKey.systemFreeSize] as? NSNumber)?.int64Value
                return freeSpace!
            } catch {
                return 0
            }
        }
    }

    class var usedDiskSpaceInBytes:Int64 {
        get {
            let usedSpace = totalDiskSpaceInBytes - freeDiskSpaceInBytes
            return usedSpace
        }
    }

}

Demo

get disk space status with Swift

Upvotes: 42

abdullahselek
abdullahselek

Reputation: 8463

You can find an another solution with using Swift 4 and extension which gives you a good option.

Here is the UIDevice extension.

extension UIDevice {

    func totalDiskSpaceInBytes() -> Int64 {
        do {
            guard let totalDiskSpaceInBytes = try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory())[FileAttributeKey.systemSize] as? Int64 else {
                return 0
            }
            return totalDiskSpaceInBytes
        } catch {
            return 0
        }
    }

    func freeDiskSpaceInBytes() -> Int64 {
        do {
            guard let totalDiskSpaceInBytes = try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory())[FileAttributeKey.systemFreeSize] as? Int64 else {
                return 0 
            }
            return totalDiskSpaceInBytes
        } catch {
            return 0
        }
    }

    func usedDiskSpaceInBytes() -> Int64 {
        return totalDiskSpaceInBytes() - freeDiskSpaceInBytes()
    }

    func totalDiskSpace() -> String {
        let diskSpaceInBytes = totalDiskSpaceInBytes()
        if diskSpaceInBytes > 0 {
            return ByteCountFormatter.string(fromByteCount: diskSpaceInBytes, countStyle: ByteCountFormatter.CountStyle.binary)
        }
        return "The total disk space on this device is unknown"
    }

    func freeDiskSpace() -> String {
        let freeSpaceInBytes = freeDiskSpaceInBytes()
        if freeSpaceInBytes > 0 {
            return ByteCountFormatter.string(fromByteCount: freeSpaceInBytes, countStyle: ByteCountFormatter.CountStyle.binary)
        }
        return "The free disk space on this device is unknown"
    }

    func usedDiskSpace() -> String {
        let usedSpaceInBytes = totalDiskSpaceInBytes() - freeDiskSpaceInBytes()
        if usedSpaceInBytes > 0 {
            return ByteCountFormatter.string(fromByteCount: usedSpaceInBytes, countStyle: ByteCountFormatter.CountStyle.binary)
        }
        return "The used disk space on this device is unknown"
    }

}

And sample usage:

UIDevice.current.totalDiskSpaceInBytes()
UIDevice.current.totalDiskSpace()
UIDevice.current.freeDiskSpaceInBytes()
UIDevice.current.freeDiskSpace()
UIDevice.current.usedDiskSpaceInBytes()
UIDevice.current.usedDiskSpace()

Upvotes: 8

arango_86
arango_86

Reputation: 4435

If you want to save time, use the following CocoaPod Library. I didn't used it but seems like it should work.

https://cocoapods.org/pods/SystemServices

Upvotes: 0

kakaiikaka
kakaiikaka

Reputation: 4487

Update with a new accurate API to get available size on disk available in iOS11. Here is the description for the new API resource key:

#if os(OSX) || os(iOS)
/// Total available capacity in bytes for "Important" resources, including space expected to be cleared by purging non-essential and cached resources. "Important" means something that the user or application clearly expects to be present on the local system, but is ultimately replaceable. This would include items that the user has explicitly requested via the UI, and resources that an application requires in order to provide functionality.
/// Examples: A video that the user has explicitly requested to watch but has not yet finished watching or an audio file that the user has requested to download.
/// This value should not be used in determining if there is room for an irreplaceable resource. In the case of irreplaceable resources, always attempt to save the resource regardless of available capacity and handle failure as gracefully as possible.
@available(OSX 10.13, iOS 11.0, *) @available(tvOS, unavailable) @available(watchOS, unavailable)
public var volumeAvailableCapacityFor Usage: Int64? { return _get(.volumeAvailableCapacityForImportantUsageKey) }
#endif

I cross compared the results from key "FileAttributeKey.systemFreeSize" and key "URLResourceKey.volumeAvailableCapacityForImportantUsageKey" and found the results returned form "volumeAvailableCapacityForImportantUsageKey" exactly matches the available storage shown on UI. Available free disk space compare Here is the swift implementation:

class var freeDiskSpaceInBytesImportant:Int64 {
    get {
        do {
            return try URL(fileURLWithPath: NSHomeDirectory() as String).resourceValues(forKeys: [URLResourceKey.volumeAvailableCapacityForImportantUsageKey]).volumeAvailableCapacityForImportantUsage!
        } catch {
            return 0
        }
    }
}

Upvotes: 16

Jivan Bhandari
Jivan Bhandari

Reputation: 860

Swift implementation of above code:- 

import UIKit

class DiskInformation: NSObject {

    var totalSpaceInBytes: CLongLong = 0; // total disk space
    var totalFreeSpaceInBytes: CLongLong = 0; //total free space in bytes

    func getTotalDiskSpace() -> String { //get total disk space
        do{
        let space: CLongLong = try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory())[FileAttributeKey.systemSize] as! CLongLong; //Check for home dirctory and get total system size
            totalSpaceInBytes = space; // set as total space
            return memoryFormatter(space: space); // send the total bytes to formatter method and return the output

        }catch let error{ // Catch error that may be thrown by FileManager
            print("Error is ", error);
        }
        return "Error while getting memory size";
    }

    func getTotalFreeSpace() -> String{ //Get total free space
        do{
            let space: CLongLong = try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory())[FileAttributeKey.systemFreeSize] as! CLongLong;
            totalFreeSpaceInBytes = space;
            return memoryFormatter(space: space);

        }catch let error{
            print("Error is ", error);
        }
        return "Error while getting memory size";
    }

    func getTotalUsedSpace() -> String{ //Get total disk usage from above variable
        return memoryFormatter(space: (totalSpaceInBytes - totalFreeSpaceInBytes));
    }

    func memoryFormatter(space : CLongLong) -> String{ //Format the usage to return value with 2 digits after decimal
        var formattedString: String;

        let totalBytes: Double = 1.0 * Double(space);
        let totalMb: Double = totalBytes / (1024 * 1024);
        let totalGb: Double = totalMb / 1024;
        if (totalGb > 1.0){
            formattedString = String(format: "%.2f", totalGb);
        }else if(totalMb >= 1.0){
            formattedString = String(format: "%.2f", totalMb);
        }else{
            formattedString = String(format: "%.2f", totalBytes);
        }
        return formattedString;
    }


}

Call it from any other class.

func getDiskInfo(){
        let diskInfo = DiskInformation();
        print("Total disk space is", diskInfo.getTotalDiskSpace(),"Gb");
        print("Total free space is", diskInfo.getTotalFreeSpace(),"Gb");
        print("Total used space is", diskInfo.getTotalUsedSpace(),"Gb");
    }

While testing the returned value, it's same as shown by other apps. At least in my iPhone 6S+. It's just the swift implementation of the above shown answer. And for me the accepted answer didn't work.

Upvotes: 1

ChrisJF
ChrisJF

Reputation: 7200

Here's my answer and why it's better.

Answer (Swift):

func remainingDiskSpaceOnThisDevice() -> String {
    var remainingSpace = NSLocalizedString("Unknown", comment: "The remaining free disk space on this device is unknown.")
    if let attributes = try? FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory()),
        let freeSpaceSize = attributes[FileAttributeKey.systemFreeSize] as? Int64 {
        remainingSpace = ByteCountFormatter.string(fromByteCount: freeSpaceSize, countStyle: .file)
    }
    return remainingSpace
}

Answer (Objective-C):

- (NSString *)calculateRemainingDiskSpaceOnThisDevice
{
    NSString *remainingSpace = NSLocalizedString(@"Unknown", @"The remaining free disk space on this device is unknown.");
    NSDictionary *dictionary = [[NSFileManager defaultManager] attributesOfFileSystemForPath:NSHomeDirectory() error:nil];
    if (dictionary) {
        long long freeSpaceSize = [[dictionary objectForKey:NSFileSystemFreeSize] longLongValue];
        remainingSpace = [NSByteCountFormatter stringFromByteCount:freeSpaceSize countStyle:NSByteCountFormatterCountStyleFile];
    }
    return remainingSpace;
}

Why it's better:

  • Utilizes Cocoa's built in library NSByteCountFormatter, meaning no crazy manual calculations from bytes to gigabytes. Apple does this for you!
  • Easily translatable: NSByteCountFormatter does this for you. E.g. When the device's language is set to English the string will read 248.8 MB but will read 248,8 Mo when set to French, et cetera for other languages.
  • A default value is given in case of an error.

Upvotes: 9

ggruen
ggruen

Reputation: 2225

Following code is Swift 3.0 version implementation of the answer previously provided by ChrisJF:

func freeSpaceInBytes() -> NSString {

    var remainingSpace = NSLocalizedString("Unknown", comment: "The remaining free disk space on this device is unknown.")

    do {
        let dictionary =  try FileManager.default.attributesOfFileSystem(forPath: NSHomeDirectory())
        let freeSpaceSize = ((dictionary[FileAttributeKey.systemFreeSize] as AnyObject).longLongValue)!
        remainingSpace = ByteCountFormatter.string(fromByteCount: freeSpaceSize, countStyle: ByteCountFormatter.CountStyle.file)
    }
    catch let error {
        NSLog(error.localizedDescription)
    }

    return remainingSpace as NSString

}

Upvotes: 2

Andrea Mario Lufino
Andrea Mario Lufino

Reputation: 7921

I know this post is a bit old, but I think this answer can help someone. If you want to know the used/free/total disk space on the device you can use Luminous. It's written in Swift. You have only to call :

Luminous.System.Disk.freeSpace()
Luminous.System.Disk.usedSpace()

or

Luminous.System.Disk.freeSpaceInBytes()
Luminous.System.Disk.usedSpaceInBytes()

Upvotes: 1

Code.Decode
Code.Decode

Reputation: 3804

UPDATE: Since a lot of time has passed after this answer and new methods/APIs have been added, please check the updated answers below for Swift etc; Since I've not used them myself, I can't vouch for them.

Original answer: I found the following solution working for me:

-(uint64_t)getFreeDiskspace {
    uint64_t totalSpace = 0;
    uint64_t totalFreeSpace = 0;
    NSError *error = nil;  
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);  
    NSDictionary *dictionary = [[NSFileManager defaultManager] attributesOfFileSystemForPath:[paths lastObject] error: &error];  

    if (dictionary) {  
        NSNumber *fileSystemSizeInBytes = [dictionary objectForKey: NSFileSystemSize];  
        NSNumber *freeFileSystemSizeInBytes = [dictionary objectForKey:NSFileSystemFreeSize];
        totalSpace = [fileSystemSizeInBytes unsignedLongLongValue];
        totalFreeSpace = [freeFileSystemSizeInBytes unsignedLongLongValue];
        NSLog(@"Memory Capacity of %llu MiB with %llu MiB Free memory available.", ((totalSpace/1024ll)/1024ll), ((totalFreeSpace/1024ll)/1024ll));
    } else {  
        NSLog(@"Error Obtaining System Memory Info: Domain = %@, Code = %ld", [error domain], (long)[error code]);
    }  

    return totalFreeSpace;
}

It returns me exactly the size that iTunes displays when device is connected to machine.

Upvotes: 158

ale_stro
ale_stro

Reputation: 816

for Swift as UIDevice extension

extension UIDevice {
    func freeDiskspace() -> NSString {
        let failedResult: String = "Error Obtaining System Memory"
        guard let path = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, NSSearchPathDomainMask.UserDomainMask, true).last else {
            return failedResult
        }
        do {
            let dictionary = try NSFileManager.defaultManager().attributesOfFileSystemForPath(path)
            if let fileSystemSizeInBytes = dictionary[NSFileSystemSize] as? UInt,
                let freeFileSystemSizeInBytes =     dictionary[NSFileSystemFreeSize] as? UInt {
                    return "Memory \(freeFileSystemSizeInBytes/1024/1024) of \(fileSystemSizeInBytes/1024/1024) Mb available."
            } else {
                    return failedResult
            }
        } catch {
            return failedResult
        }
    }
}

How to use: 

print("\(UIDevice.currentDevice().freeDiskspace())")

Output will be:

Memory 9656 of 207694 Mb available.

Upvotes: 1

Juan Boero
Juan Boero

Reputation: 6427

ChrisJF answer in Swift 2.1 version:

func freeSpaceInBytes() -> NSString{

    var remainingSpace = NSLocalizedString("Unknown", comment: "The remaining free disk space on this device is unknown.")

    do {

        let dictionary =  try NSFileManager.defaultManager().attributesOfFileSystemForPath(NSHomeDirectory())
        freeSpaceSize = (dictionary[NSFileSystemFreeSize]?.longLongValue)!
        remainingSpace = NSByteCountFormatter.stringFromByteCount(freeSpaceSize, countStyle: NSByteCountFormatterCountStyle.File)

    }
    catch let error as NSError {

        error.description
        NSLog(error.description)

    }

    return remainingSpace

}

Upvotes: 0

RubenSandwich
RubenSandwich

Reputation: 379

If your looking to get the the remaining free space using Swift it is slightly different. You need to use attributesOfFileSystemForPath() instead of attributesOfItemAtPath():

func deviceRemainingFreeSpaceInBytes() -> Int64? {
    let documentDirectoryPath = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)
    var attributes: [String: AnyObject]
    do {
        attributes = try NSFileManager.defaultManager().attributesOfFileSystemForPath(documentDirectoryPath.last! as String)
        let freeSize = attributes[NSFileSystemFreeSize] as? NSNumber
        if (freeSize != nil) {
            return freeSize?.longLongValue
        } else {
            return nil
        }
    } catch {
        return nil
    }
}

Edit: Updated for Swift 1.0
Edit 2: Updated for safety, using Martin R's answer.
Edit 3: Updated for Swift 2.0 (by dgellow)

Upvotes: 13

Markus
Markus

Reputation: 1177

Important clarification (at least for me). If I connect my iPod to my Mac this is the info showed by iTunes App.

iPod memory informations from iTunes app

When I use the above code: 

long long freeSpace = [[[[NSFileManager defaultManager] attributesOfFileSystemForPath:NSHomeDirectory() error:nil]
                            objectForKey:NSFileSystemFreeSize] longLongValue];

NSString *free1 = [NSByteCountFormatter stringFromByteCount:freeSpace countStyle:NSByteCountFormatterCountStyleFile];

[label1 setText:free1];

NSString *free2 = [NSByteCountFormatter stringFromByteCount:freeSpace countStyle:NSByteCountFormatterCountStyleBinary];

[label2 setText:free2];

The countStyle NSByteCountFormatterCountStyleFile show me: 17,41 GB

The countStyle NSByteCountFormatterCountStyleBinary show me: 16,22 GB

16,22 GB (NSByteCountFormatterCountStyleBinary) It is EXACTLY the number that iTunes App show me when I connect my iPod to my Mac.

Upvotes: 7

Robert
Robert

Reputation: 38223

For iOS >= 6.0 you can use the new NSByteCountFormatter. This code gets the number of free bytes remaining as a formatted string. 

NSError *error = nil;
NSArray * const paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSDictionary * const pathAttributes = [[NSFileManager defaultManager] attributesOfFileSystemForPath:[paths firstObject] error:&error];
NSAssert(pathAttributes, @"");
NSNumber * const fileSystemSizeInBytes = [pathAttributes objectForKey: NSFileSystemFreeSize];
const long long numberOfBytesRemaining = [fileSystemSizeInBytes longLongValue];
NSByteCountFormatter *byteCountFormatter = [[NSByteCountFormatter alloc] init];
NSString *formattedNmberOfBytesRemaining = [byteCountFormatter stringFromByteCount:numberOfBytesRemaining];

Upvotes: 3

0x8BADF00D
0x8BADF00D

Reputation: 7718

If you need formatted string with size you can take a look at nice library on GitHub:

#define MB (1024*1024)
#define GB (MB*1024)

@implementation ALDisk

#pragma mark - Formatter

+ (NSString *)memoryFormatter:(long long)diskSpace {
    NSString *formatted;
    double bytes = 1.0 * diskSpace;
    double megabytes = bytes / MB;
    double gigabytes = bytes / GB;
    if (gigabytes >= 1.0)
        formatted = [NSString stringWithFormat:@"%.2f GB", gigabytes];
    else if (megabytes >= 1.0)
        formatted = [NSString stringWithFormat:@"%.2f MB", megabytes];
    else
        formatted = [NSString stringWithFormat:@"%.2f bytes", bytes];

    return formatted;
}

#pragma mark - Methods

+ (NSString *)totalDiskSpace {
    long long space = [[[[NSFileManager defaultManager] attributesOfFileSystemForPath:NSHomeDirectory() error:nil] objectForKey:NSFileSystemSize] longLongValue];
    return [self memoryFormatter:space];
}

+ (NSString *)freeDiskSpace {
    long long freeSpace = [[[[NSFileManager defaultManager] attributesOfFileSystemForPath:NSHomeDirectory() error:nil] objectForKey:NSFileSystemFreeSize] longLongValue];
    return [self memoryFormatter:freeSpace];
}

+ (NSString *)usedDiskSpace {
    return [self memoryFormatter:[self usedDiskSpaceInBytes]];
}

+ (CGFloat)totalDiskSpaceInBytes {
    long long space = [[[[NSFileManager defaultManager] attributesOfFileSystemForPath:NSHomeDirectory() error:nil] objectForKey:NSFileSystemSize] longLongValue];
    return space;
}

+ (CGFloat)freeDiskSpaceInBytes {
    long long freeSpace = [[[[NSFileManager defaultManager] attributesOfFileSystemForPath:NSHomeDirectory() error:nil] objectForKey:NSFileSystemFreeSize] longLongValue];
    return freeSpace;
}

+ (CGFloat)usedDiskSpaceInBytes {
    long long usedSpace = [self totalDiskSpaceInBytes] - [self freeDiskSpaceInBytes];
    return usedSpace;
}

Upvotes: 26

David Hoerl
David Hoerl

Reputation: 41652

Revised source using unsigned long long:

- (uint64_t)freeDiskspace
{
    uint64_t totalSpace = 0;
    uint64_t totalFreeSpace = 0;

    __autoreleasing NSError *error = nil;  
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);  
    NSDictionary *dictionary = [[NSFileManager defaultManager] attributesOfFileSystemForPath:[paths lastObject] error: &error];  

    if (dictionary) {  
        NSNumber *fileSystemSizeInBytes = [dictionary objectForKey: NSFileSystemSize];  
        NSNumber *freeFileSystemSizeInBytes = [dictionary objectForKey:NSFileSystemFreeSize];
        totalSpace = [fileSystemSizeInBytes unsignedLongLongValue];
        totalFreeSpace = [freeFileSystemSizeInBytes unsignedLongLongValue];
        NSLog(@"Memory Capacity of %llu MiB with %llu MiB Free memory available.", ((totalSpace/1024ll)/1024ll), ((totalFreeSpace/1024ll)/1024ll));
    } else {  
        NSLog(@"Error Obtaining System Memory Info: Domain = %@, Code = %d", [error domain], [error code]);  
    }  

    return totalFreeSpace;
}

EDIT: it seems someone edited this code to use 'uint64_t' instead of 'unsigned long long'. While in the foreseeable future this should be just fine, they are not the same. 'uint64_t' is 64 bits and will always be that. In 10 years 'unsigned long long' might be 128. its a small point but why I used unsignedLongLong.

Upvotes: 60

Christopher Lloyd
Christopher Lloyd

Reputation: 664

Don't use 'unsigned', it is only 32 bits which will overflow past 4GB, which is less than the typical iPad/iPhone free space. Use unsigned long long (or uint64_t), and retrieve the value out of the NSNumber as a 64-bit int too using unsignedLongLongValue.

Upvotes: 13

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