#!/bin/bash

set -e

$NFT add table t

$NFT add chain t c1

$NFT add chain t c2

$NFT add rule t c1 tcp dport vmap { 1 : jump c2 }

# kernel should return EBUSY

$NFT delete chain t c2 2>/dev/null || exit 0

echo "E: deleted a busy chain?" >&2

exit 1