[in, out, unique, size_is(*pcbIdSize)] Returns the ID of the change unit.
pcbIdSize
[in, out] Specifies the number of bytes in pbChangeUnitId. Returns the number of bytes required to retrieve the specified field value if pbChangeUnitId is too small; otherwise, returns the number of bytes written.
HRESULT_FROM_WIN32(ERROR_MORE_DATA) if pbChangeUnitId is not large enough to receive the field value. In this case, pcbIdSize returns the required number of bytes.