This function sets the pointer to be used to indicate the hot spot while dragging over the current target.
The pointer that is set with DrgSetDragPointer is used only while it is over the current target. The pointer is reset to the default when a new target is dragged over.
This function can be used by an application to provide meaningful augmentation emphasis for an operation that is unknown to the system (for example, swap).
When the drag pointer is successfully set, TRUE is returned.