Re: [lwip-users] Half-Open detecting

[Kieran Mansley]

On Thu, 2011-04-21 at 21:45 +0800, Steven Woody wrote:
> 
> I was reading the code, my understand is:  when a new SYN comes, my
> old pcb must be in active pcbs list, so the new coming SYN will not
> get matched in this list, and it also impossible getting match in
> listen queue or tw queue. So, this SYN will be dropped.  Am I
> understand right?

An incoming SYN where you have nothing that matches in the
tcp_listen_pcbs listen will get (I think, from memory) a TCP reset
packet sent in response.  If you want to be notified of the SYN you have
to have a listening PCB.

Kieran