title: how to control beaglebone gpio pins
body: <p>I'm trying to make a program for beaglebone to let me control the gpio pins.
  I tried to use sprintf() but doesn't accept input as I know.</p>
  
  <p>I have to re-write couple files in the beaglebone like</p>
  
  <p>gpio export       active the pin
  gpio gpio$pin/direction    pin mode in/out
  gpio gpio$pin/value   pin value 1/0</p>
  
  <p>guys..!! just need a idea how to accomplish my goal.</p>
  
  <p>I'm newbie in c++.
  any information or comment I'll appreciated 
  thks guys for your time.</p>