[lwip-users] Closing a client connection via (flags & TCP_FIN)

[Tom C. Barker]

Hello,

 

Currently I have an SMTP client which closes its connection

via a poll method: when the connection is in CLOSE_WAIT,

the poll method will perform tcp_close. This algorithm is

the only example I have seen (when using tcp_connect

to get the conversation started).

 

I was considering working around all of the polling by making a

call to TCP_EVENT_RECV(pcb, recv_data, ERR_OK, err) where

the _RECV function would notice the connection in CLOSE_WAIT

and would call tcp_close. Alternatively, could I just call tcp_close()

instead of the _RECV function?

 

Thanks in advance for your advice.

 

Tom

 

 

tcp_in.c:

 

  case ESTABLISHED:
    tcp_receive(pcb);
    if (flags & TCP_FIN) {
      tcp_ack_now(pcb);
      pcb->state = CLOSE_WAIT;
      TCP_EVENT_RECV(pcb, recv_data, ERR_OK, err);  //call the application to close

      ---- or -----

      tcp_close(pcb);
    }
    break;