#===== Open I/O pipes and run the process
  $pid = open3(\*DEV_NULL, \*OUT, \*ERR, "my_long_process");
  
  #===== Print the results
  while (<OUT>)
  {
    $buffer .= $_;
  
    #===== Update the display cache
    $cache->set($session, [0, $buffer]);
  }