- Apparently  $?loginsh is not a good indicator of whether tcsh is
  interactive (bad Google...) so we'll look for 'setup.csh' in the
  current directory and if it is present assume it is the hcana/
  directory.
- The if($?prompt) clause should print some info text if you're
  interactive.  (Although it's not definitive either -- dammit csh.)

-- Brad