title: how to set mark by nfq_set_verdict_mark
body: <p>i call nfq_set_verdict_mark  to set mark, then i want use this mark in other chain. but the mark is likely not  active.
  my iptables chain as follow:</p>
  
  <pre><code>iptables -A FORWARD -m length --length 0:1500 -j NFQUEUE --queue-balance 50:53;
  iptables -A OUTPUT -m mark --mark 17 -j DROP
  </code></pre>
  
  <p>i write a program use to get the packet from NFQUEUE, then match some protocol, eg, when match HTTP, set mark = 17, then call the nfq_set_verdict_mark
  nfq_set_verdict_mark(qh, id, verdict, htonl(mark), 0, NULL);</p>
  
  <p>however, the http protocol can't be drop, i thought the mark may be not active. how can i do, mark in program then do some action by mark.
  help me, thanks</p>