Can Joint references be retrieved from the Tail End?

A joint is a component on object A, which takes Rigidbody B as a property, the ConnectedBody.

It's easy to read the connectedBody of A if you have A. But what if you have B? How do you find A?
That is, is there any way, given a rigidbody, to find joints that are connected TO it (from other bodies)

 

I don't think so.

 

If it's not possible, that's unfortunate. but it would also defy logic.

Surely in order for joint chains to function, PhysX would need to keep lists of joints connected to each body, so it can be known what else to move when that body moves. Perhaps that information just isn't exposed?

 

http://stackoverflow.com/questions/23609803/finding-the-joint-from-the-connected-body

It doesn't appear so. This is the most relevant information I could find on this topic.