Description:
------------
I had trouble running the following using php 5.3.2: 
<?php
 $username = 'dummy value';
 function fetchUsername(){
   global $username;
  //Imitate retrieval
  $username ='Sample Value';
}

fetchUsername();
echo $username;

?>

The above printed the dummy value (dummy value). Am i missing something? Pliz help


Test script:
---------------
<?php
 $username = 'dummy value';
 function fetchUsername(){
   global $username;
  //Imitate retrieval
  $username ='Sample Value';
}

fetchUsername();
echo $username; //Prints 'dummy value'

?>