When a program uses a multicast consumer to receive messages, EMS can detect conditions that may indicate a problem, and notify the client program by returning an error status code. The client application can then take the appropriate action.
This callback provides a pathway for alerting a client program of multicast problems. The program implements this callback and registers it. When the client library detects a multicast problem, it calls this callback and passes it the appropriate EMS objects, a status code that identifies the problem, and a detailed description of the problem. This callback is invoked for each consumer that is affected by the multicast warning or error. Some applications may just simply log the problem; others may take further measures.