show_404($page = '', $log_error = TRUE)

password_needs_rehash()

password_get_info($hash)

function_usable($function_name)

password_verify($password, $hash)

get_instance()

mb_substr($str, $start[, $length = NULL[, $encoding = NULL]])

get_mimes()

remove_invisible_characters($str[, $url_encoded = TRUE])

is_https()