Get an array with the names fields of a determined type of content

$type_name = 'contacto'; #Content Type name
  $type = content_types($type_name); #Get all the info of the type
 
  if ($type) {
 
    $return = array();
 
     foreach ($type['fields'] as $field_name => $field) {
 
          $return[] = $field['field_name'];
     }      
 
     $return = implode("\n", $return);    
  } else {
 
        $return = FALSE;    
    }