Description

The Void object is the unique singleton object that returns RC_Void to all requests.

The Void key occurs whenever a key register or node slot holds no other key. Void keys are created in a variety of ways:

• When a Node is created, all slots contain void keys.
• The Clear Node operation on a Node stores void keys in all slots of the node.
• When an object is destroyed, all outstanding keys to that object are replaced with void keys. This conversion may occur at any time, but it is guaranteed to occur before such a key is invoked.
• When a resume key is invoked, all outstanding resume keys to the same process are replaced with void keys. This conversion may occur at any time, but it is guaranteed to occur before such a key is invoked.

The void key returns RC_Void to all requests. By (strong) convention, the RC_Void return code is generally avoided by other objects in order to allow callers to discern when an object has been destroyed.