Instance Property


The identifier for the shared container into which files in background URL sessions should be downloaded.


@property(copy) NSString *sharedContainerIdentifier;


To create a URL session for use by an app extension, set this property to a valid identifier for a container shared between the app extension and its containing app.

For information about app extensions, see App Extension Programming Guide.

See Also

Setting General Properties


The background session identifier of the configuration object.


A dictionary of additional headers to send with requests.


The type of network service for all tasks within sessions based on this configuration.


A Boolean value that determines whether connections should be made over a cellular network.


The timeout interval to use when waiting for additional data.


The maximum amount of time that a resource request should be allowed to take.


A Boolean value that indicates whether the session should wait for connectivity to become available, or fail immediately.

Beta Software

This documentation contains preliminary information about an API or technology in development. This information is subject to change, and software implemented according to this documentation should be tested with final operating system software.

Learn more about using Apple's beta software