Function for getting the (X,Y,Z) of a attachment point on a unit

I am currently trying to emulate a multiple life drain and I was wondering if there is a function that takes an attachment point (i.e. head, chest origin) on a unit and returns a X,Y (location of unit) and Z (height of the attachment point).

Realistically I only need a function to get the height of the attachment point, because the X and Y can easily be done with the position of the unit
Thanks

EDIT: Sorry, i completly misunderstood your post.
I have removed old post.

Impossible, sorry pal. You can get the XYZ of the unit, but you can't get any information about attachment points in-game.

No.

You can however open the model and check the offsets for yourself, they're in the pivotpoint section. If you need any help with this ask in the mdl section.
Then when you got the coords just store them in a 3d-array and you can get them from that.