Instance Method


Returns a bookmark for the URL, created with specified options and resource values.


- (NSData *)bookmarkDataWithOptions:(NSURLBookmarkCreationOptions)options includingResourceValuesForKeys:(NSArray<NSURLResourceKey> *)keys relativeToURL:(NSURL *)relativeURL error:(NSError * _Nullable *)error;



Options taken into account when creating the bookmark for the URL. The possible flags (which can be combined with bitwise OR operations) are described in NSURLBookmarkCreationOptions.

To create a security-scoped bookmark to support App Sandbox, include the NSURLBookmarkCreationWithSecurityScope flag. When you later resolve the bookmark, you can use the resulting security-scoped URL to obtain read/write access to the file-system resource pointed to by the URL.

If you instead want to create a security-scoped bookmark that, when resolved, enables you to obtain read-only access to a file-system resource, bitwise OR this parameter’s value with both the NSURLBookmarkCreationWithSecurityScope option and the NSURLBookmarkCreationSecurityScopeAllowOnlyReadAccess option.


An array of names of URL resource properties to store as part of the bookmark. You can later access these values (without resolving the bookmark) by calling the resourceValuesForKeys:fromBookmarkData: method.

The values of these properties must be of a type that the bookmark generation code can serialize. Specifically, the values can contain any of the following primitive types:

  • NSString or CFString

  • NSData or CFData

  • NSDate or CFDate

  • NSNumber or CFNumber

  • CFBoolean


  • kCFNull or NSNull


In addition, the properties can contain the following collection classes:

  • NSArray or CFArray containing only the above primitive types

  • NSDictionary or CFDictionary with NSString or CFString keys, in which all values contain only the above primitive types


The URL that the bookmark data will be relative to.

If you are creating a security-scoped bookmark to support App Sandbox, use this parameter as follows:

  • To create an app-scoped bookmark, use a value of nil.

  • To create a document-scoped bookmark, use the absolute path (despite this parameter’s name) to the document file that is to own the new security-scoped bookmark.

App Sandbox does not restrict which URL values may be passed to this parameter.


The error that occurred in the case that the bookmark data cannot be created.

Return Value

A bookmark for the URL.


This method returns bookmark data that can later be resolved into a URL object for a file even if the user moves or renames it (if the volume format on which the file resides supports doing so).

You can also use this method to create a security-scoped bookmark to support App Sandbox. Before you do so, you must first enable the appropriate entitlements for your app, as described in Enabling Security-Scoped Bookmark and URL Access. In addition, be sure to understand the behavior of the options and relativeURL parameters.

For an app-scoped bookmark, no sandboxed app other than the one that created the bookmark can obtain access to the file-system resource that the URL (obtained from the bookmark) points to. Specifically, a bookmark created with security scope fails to resolve if the caller does not have the same code signing identity as the caller that created the bookmark.

For a document-scoped bookmark, any sandboxed app that has access to the bookmark data itself, and has access to the document that owns the bookmark, can obtain access to the resource.

See Also

Working with Bookmark Data

+ bookmarkDataWithContentsOfURL:error:

Initializes and returns bookmark data derived from an alias file pointed to by a specified URL.

+ resourceValuesForKeys:fromBookmarkData:

Returns the resource values for properties identified by a specified array of keys contained in specified bookmark data.

+ writeBookmarkData:toURL:options:error:

Creates an alias file on disk at a specified location with specified bookmark data.

- startAccessingSecurityScopedResource

In an app that has adopted App Sandbox, makes the resource pointed to by a security-scoped URL available to the app.

- stopAccessingSecurityScopedResource

In an app that adopts App Sandbox, revokes access to the resource pointed to by a security-scoped URL.


Options used when creating file bookmark data


Options used when creating bookmark data.


Options used when resolving bookmark data.