Global Variable

NSURLFileResourceIdentifierKey

The resource’s unique identifier, returned as an id (read-only).

Declaration

const NSURLResourceKey NSURLFileResourceIdentifierKey;

Discussion

This identifier can be used to determine equality between file system resources with the isEqual: method. Two resources are equal if they have the same file-system path or if their paths link to the same inode on the same file system.

The value of this identifier is not persistent across system restarts.

See Also

File Keys

NSURLFileAllocatedSizeKey

Key for the total size allocated on disk for the file, returned as an NSNumber object (read-only).

NSURLFileProtectionType

Protection level values that can be associated with a URL resource key.

NSURLFileResourceTypeKey

The resource’s object type, returned as an NSString object (read-only). See NSURLFileResourceType for possible values.

NSURLFileSecurityKey

The resource’s security information, returned as an NSFileSecurity object (read-write).

NSURLFileSizeKey

Key for the file’s size in bytes, returned as an NSNumber object (read-only).

NSURLIsAliasFileKey

Key for determining whether the file is an alias, returned as a Boolean NSNumber object (read-only).

NSURLIsPackageKey

Key for determining whether the resource is a file package, returned as a Boolean NSNumber object (read-write in macOS 10.8 and later, read-only in previous versions). A true value means that the resource is a file package.

NSURLIsRegularFileKey

Key for determining whether the resource is a regular file, as opposed to a directory or a symbolic link. Returned as a Boolean NSNumber object (read-only).

NSURLPreferredIOBlockSizeKey

The optimal block size to use when reading or writing this file's data, returned as an NSNumber object, or nil if the preferred size is not available (read-only).

NSURLTotalFileAllocatedSizeKey

Key for the total allocated size of the file in bytes, returned as an NSNumber object (read-only). This includes the size of any file metadata.

NSURLTotalFileSizeKey

Key for the total displayable size of the file in bytes, returned as an NSNumber object (read-only). This includes the size of any file metadata.