cache_delete([$segment_one = ''[, $segment_two = '']])

timeout($seconds = 5)

read_dir($path[, $preserve_filepath = TRUE[, $root_path = NULL]])

force_download([$filename = ''[, $data = ''[, $set_mime = FALSE]]])

initialize($params)

changedir($path[, $suppress_debug = FALSE])

character_limiter($str[, $n = 500[, $end_char = '…']])

has_rule($field)

set_item($item, $value)

set_output($output)