-- A correctly-written Peh Tape is expected to produce a Verdict.
      -- On Unix, we will give it to the caller process via the usual means:
      case Verdict is
         
         -- Tape produced a Verdict of 'Yes' :
         when Yes =>
            Quit(Yes_Code);
            
         -- Tape produced a Verdict of 'No'  :
         when No =>
            Quit(No_Code);
            
            -- Tape ran to completion without producing any Verdict at all.
            -- Outside of simple test scenarios, noob explorations, etc.,
            -- this usually means that there is a logical mistake in the
            -- Tape somewhere, and we will warn the operator:
         when Mu =>
            Achtung("WARNING: Tape terminated without a Verdict.");
            Quit(Mu_Code);
            
      end case;
      
      -- If the Tape aborted on account of a fatal error condition (e.g. div0)
      -- Peh will Quit(Sad_Code) (see E(..) in ffa_calc.adb .)
      -- Therefore, Peh ALWAYS returns one of FOUR possible Unix return-codes:
      -- -2, -1, 0, 1. (see os.ads .)