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

password_needs_rehash()

password_get_info($hash)

hash_equals($known_string, $user_string)

function_usable($function_name)

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

password_verify($password, $hash)

password_hash($password, $algo[, $options = array()])

mb_strpos($haystack, $needle[, $offset = 0[, $encoding = NULL]])

is_https()