title: Can I get the amount of time for which a key is pressed on a keyboard
body: <p>I am working on a project in which I have to develop bio-passwords based on user's keystroke style. 
  Suppose a user types a password for 20 times, his keystrokes are recorded, like </p>
  
  <p>holdtime : time for which a particular key is pressed. 
  digraph time : time it takes to press a different key.</p>
  
  <p>suppose a user types a password  " COMPUTER".  I need to know the time for which every key is pressed. something like :</p>
  
  <p>holdtime for the above password is</p>
  
  <p>C-- 200ms
  O-- 130ms
  M-- 150ms
  P-- 175ms
  U-- 320ms
  T-- 230ms
  E-- 120ms
  R-- 300ms</p>
  
  <p>The rational behind this is , every user will have a different holdtime. Say a old person is typing the password, he will take more time then a student. And it will be unique to a particular person. 
  To do this project, I need to record the time for each key pressed. 
  I would greatly appreciate if anyone can guide me in how to get these times. </p>
  
  <p>Editing from here..
  Language is not important, but I would prefer it in C. I am more interested in getting the dataset.</p>