title: How can I "watch" a file for modification / change?
body: <p>I would like to invoke my <code>chrome</code> or <code>firefox</code> browser when a file that I specify is modified. How could I "watch" that file to do something when it gets modified?</p>
  
  <p>Programmatically it seems the steps are.. basically set a never ending interval every second or so and cache the initial modification date, then compare the date every second, when it changes invoke X.</p>