gistfile1.txt

function MYMOD_drush_command(){
  $items = array();
  $items['loc-update'] = array(
    'description' => dt('Run Location update'),
    'arguments'   => array(
      'arg1'    => dt('Optional User ID'),
    ),
    'examples' => array(
      'Standard example' => 'drush loc-update',
      'Argument example' => 'drush loc-update 5',
    ),
    'aliases' => array('gloc'),
  );
  return $items;
}

function drush_MYMOD_loc_update($uid){
  echo "test";
}