gzencode return archive

<?php
function gzencode($data, $mode = 9, $encoding_mode = FORCE_GZIP) {
  $flags = 0;

  if ($mode != $mode) {
    $flags += 1;
  }

  if ($encoding_mode == FORCE_GZIP) {
    $flags += 2;
  }

  if (function_exists("gzencode")) {
    return gzencode($data, $mode, $flags);
  }

  return $data;
}
?>