Type Property

generationIdentifierKey

An opaque generation identifier, returned as an id <NSCopying, NSCoding, NSObject> (read-only)

Declaration

static let generationIdentifierKey: URLResourceKey

Discussion

The generation identifier can be compared using isEqual: to determine if the data in a document has been modified. For URLs which refer to the same file inode, the generation identifier changes when the data in the file's data fork is changed. Changes to extended attributes or other file system metadata do not change the identifier. For URLs which refer to the same directory inode, the generation identifier changes when direct children of that directory are added, removed or renamed. Changes to the data of the direct children of that directory does not change the generation identifier. The identifier persists across system restarts. It is tied to a specific document on a specific volume and is not transferred when the document is copied to another volume. This property is not supported by all volumes.

See Also

Other Resource Keys

static let keysOfUnsetValuesKey: URLResourceKey

Key for the resource properties that have not been set after the setResourceValues(_:) method returns an error, returned as an array of NSString objects.

static let quarantinePropertiesKey: URLResourceKey
static let addedToDirectoryDateKey: URLResourceKey

The time at which the resource’s was created or renamed into or within its parent directory, returned as an NSDate. Inconsistent behavior may be observed when this attribute is requested on hard-linked items. This property is not supported by all volumes. (read-only)

static let attributeModificationDateKey: URLResourceKey

The time at which the resource’s attributes were most recently modified, returned as an NSDate object if the volume supports attribute modification dates, or nil if attribute modification dates are unsupported (read-only).

static let contentAccessDateKey: URLResourceKey

The time at which the resource was most recently accessed.

static let contentModificationDateKey: URLResourceKey

The time at which the resource was most recently modified.

static let creationDateKey: URLResourceKey

The time at which the resource was created.

static let customIconKey: URLResourceKey

The icon stored with the resource, returned as an NSImage object, or nil if the resource has no custom icon.

static let documentIdentifierKey: URLResourceKey

The document identifier returned as an NSNumber (read-only).

static let effectiveIconKey: URLResourceKey

The resource’s normal icon, returned as an NSImage object (read-only).

static let hasHiddenExtensionKey: URLResourceKey

Key for determining whether the resource’s extension is normally removed from its localized name, returned as a Boolean NSNumber object (read-write).

static let isExcludedFromBackupKey: URLResourceKey

Key for determining whether the resource is excluded from all backups of app data, returned as a Boolean NSNumber object (read-write).

static let isExecutableKey: URLResourceKey

Key for determining whether the current process (as determined by the EUID) can execute the resource (if it is a file) or search the resource (if it is a directory), returned as a Boolean NSNumber object (read-only).

static let isHiddenKey: URLResourceKey

Key for determining whether the resource is normally not displayed to users, returned as a Boolean NSNumber object (read-write).

static let isReadableKey: URLResourceKey

Key for determining whether the current process (as determined by the EUID) can read the resource, returned as a Boolean NSNumber object (read-only).

static let isSymbolicLinkKey: URLResourceKey

Key for determining whether the resource is a symbolic link, returned as a Boolean NSNumber object (read-only).

static let isSystemImmutableKey: URLResourceKey

Key for determining whether the resource's system immutable bit is set, returned as a Boolean NSNumber object (read-write).

static let isUserImmutableKey: URLResourceKey

Key for determining whether the resource's user immutable bit is set, returned as a Boolean NSNumber object (read-write).

static let isWritableKey: URLResourceKey

Key for determining whether the current process (as determined by the EUID) can write to the resource, returned as a Boolean NSNumber object (read-only).

static let labelColorKey: URLResourceKey

The resource’s label color, returned as an NSColor object, or nil if the resource has no label color (read-only).

static let labelNumberKey: URLResourceKey

The resource’s label number, returned as an NSNumber object (read-write).

static let linkCountKey: URLResourceKey

The number of hard links to the resource, returned as an NSNumber object (read-only).

static let localizedLabelKey: URLResourceKey

The resource’s localized label text, returned as an NSString object, or nil if the resource has no localized label text (read-only).

static let localizedNameKey: URLResourceKey

The resource’s localized or extension-hidden name, returned as an NSString object (read-only).

static let localizedTypeDescriptionKey: URLResourceKey

The resource’s localized type description, returned as an NSString object (read-only).

static let nameKey: URLResourceKey

The resource’s name in the file system, returned as an NSString object (read-write).

static let pathKey: URLResourceKey

The file system path for the URL, returned as an NSString object (read-only).

static let canonicalPathKey: URLResourceKey
static let tagNamesKey: URLResourceKey

The names of tags attached to the resource, returned as an array of NSString values (read-write).

static let typeIdentifierKey: URLResourceKey

The resource’s uniform type identifier (UTI), returned as an NSString object (read-only).

Beta Software

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