except ifc_setup deals in node_ids and, where i make the call, i
am dealing with node IP addresses. also, we are  in the habit (i am
anyway) of playing fast and loose with scoping. specifically, i use
a global scope for my database queries, statement handles and ROWS.
turns out that while in the subroutines GetCurrentOS() and OSFeatureSupported(), i was overwriting a value i was setting before (before i had called
the subroutines) and using after the calls. I think the scripts are
getting sufficiently complicated that we should use better scoping --
we can think about that after the demo.