Re: [lwip-users] endless loop in netconn_write

[Kieran Mansley]

On Wed, 2006-07-26 at 12:10 +0200, E. Spijksma wrote:
> We've been studying the debug info the lwipstack provides and noticed that 
> this 
> happens with multiple threads to the stack.
> 
> Sometimes a "tcp_receive: received FIN" isn't followed by
> TCP connection closed 3613 -> 80.
> 
> tcp_pcb_purge
> 
> This would mean the buffers aren't purged and wouldn't this end up in 
> a loop in netconn_write() because len = 0 due to unpurged data in the send
> buffer?

I'm not sure about the details of your problem, but a received FIN will
not result in a closed connection until the process at the local end
also closes it.  The received FIN just means that the other end will not
send any more data, but the connection is still usable for the local end
to send.

Kieran