RosettaCodeData/Task/Rate-counter/PicoLisp/rate-counter-1.l

(prin "Hit a key ... ")
(key)
(prinl)
(let Usec (usec)
   (prin "Hit another key ... ")
   (key)
   (prinl)
   (prinl "This took " (format (- (usec) Usec) 6) " seconds") )