[lwip-users] How to detect FIN / remote closed connection with netconn API?

[Couch, Kelly J]

I am using lwip 1.4.0 and must utilize netconn_new_with_callback

 

My reader thread blocks on a queue that is written to by the netconn_callback.  I merely detect when NETCONN_EVT_RCVPLUS is the event and write to a queue, then the blocking thread wakes up and processes the incoming data.

 

I have implemented something very similar to what is suggested via this thread: http://lists.gnu.org/archive/html/lwip-users/2011-02/msg00026.html

 

I have observed that a NETCONN_EVT_RCVPLUS with a ‘len’ of 0 coincides with connection events (but am uncertain if this is the ONLY reason for a 0 length event), like a newly established connection or a disconnected connection, however I can find no flags or other mechanism to confirm that the connection is indeed closed?

 

As a debugging attempt, I have tried using “netconn_set_nonblocking(pxNewConnection, TRUE);“ on a newly established connection, but calls to netconn_recv still block!?

 

It appears I can set the recv_timeout, which does return, but is not really the desired mechanism.

 

Any help is greatly appreciated.

 

Thanks.

 

-Kelly