MIDIEntityRef
An entity that a device owns and that contains endpoints.
Declaration
typealias MIDIEntityRef = MIDIObjectRefDiscussion
An entity object derives from MIDIObjectRef, and its owning object is a MIDIDeviceRef.
Devices may have multiple logically distinct subcomponents; for example, a MIDI synthesizer and a pair of MIDI ports are addressable using a USB port. By grouping a device’s endpoints into entities, the system has enough information for an app to make reasonable assumptions about how to communicate bidirectionally with each entity, as required by MIDI librarian apps.