Sorry, I had assumed it was just a generic term for exporting packets. I
Googled pcap and hopefully these are the right thing.
On 13/11/14 14:29, Simon Goldschmidt wrote:
> Text files?? Really?? Please send pcap files! I want to see the traffic
> in wireshark, not in my text editor!
> Simon
> *Gesendet:* Donnerstag, 13. November 2014 um 15:04 Uhr
> *Von:* "Robert Wood" <address@hidden>
> *An:* address@hidden
> *Betreff:* Re: [lwip-users] Pulling data from a server using HTTP with lwIP
> Hopefully these two text files get attached the the mailing list. If
> not, I'll send them directly.
>
> One sends no GET command and the handshake works correctly.
>
> The other sends the GET command, but not the ACK.
>
> Hope that helps. :~)
>
> On 13/11/14 13:51, Simon Goldschmidt wrote:
> > I don't think I really get what your problem is. Could you send a small
> > pcap the packets in question?
> > Simon
> > *Gesendet:* Donnerstag, 13. November 2014 um 14:41 Uhr
> > *Von:* "Robert Wood" <address@hidden>
> > *An:* address@hidden
> > *Betreff:* Re: [lwip-users] Pulling data from a server using HTTP
> with lwIP
> > Ah, no, I wasn't aware of that at all.
> >
> > I still don't know how I'd do that as, if left to its own devices, the
> > stack sends the ACK out anyway and I have no idea how I'd tack that data
> > on to the ACK.
> >
> > It seems like the low level stuff does take care of that for you. Is it
> > the case that I can poll something to wait for the stack to inform me
> > that the ACK has gone out and I can send stuff or am I looking at it the
> > wrong way?
> >
> > Thanks,
> >
> > Rob
> >
> > On 13/11/14 13:31, Simon Goldschmidt wrote:
> > > Robert,
> > > are you aware that it's legal for the ACK you are missing to contain
> > > data also? In this case the packets would look like this:
> > > SYN ->
> > > <- SYN/ACK
> > > ACK+DATA(GET) ->
> > > This is what I was trying to explain in my last mail...
> > > Simon
> > > *Gesendet:* Donnerstag, 13. November 2014 um 14:22 Uhr
> > > *Von:* "Robert Wood" <address@hidden>
> > > *An:* address@hidden
> > > *Betreff:* Re: [lwip-users] Pulling data from a server using HTTP
> > with lwIP
> > > It's not quite like that, I'm not explaining very well. I'll try
> > again. :~)
> > >
> > > If I send the GET command out, then my board does not send the ACK to
> > > the server for the SYN, SYN ACK, ACK handshake. This is what happens.
> > > Bear in mind the lwIP board is the client in this case.
> > >
> > > Here are two different In both cases I do this in the lwIP client
> thread:
> > >
> > > IP4_ADDR(&local_ip,emacIPADDR0,emacIPADDR1,emacIPADDR2,emacIPADDR3);
> > > rc1 = netconn_bind ( xNetConn, &local_ip, 0 );
> > > IP4_ADDR(&remote_ip,192,168,0,87);
> > > rc2 = netconn_connect ( xNetConn, &remote_ip, 80 );
> > >
> > > Scenario 1:
> > >
> > > In this case I do not send a GET request out.
> > >
> > > Client -> SYN (Server receives this)
> > > Server -> SYN ACK (Client receives this)
> > > Client -> ACK (Server receives this)
> > >
> > > Scenario 2:
> > >
> > > In this case I send the GET command out.
> > >
> > > Client -> SYN (Server receives this)
> > > Server -> SYN ACK (Client receives this)
> > > Client -> GET Command
> > >
> > > So, in scenario 2, the client is not sending out the ACK in the initial
> > > handshake. I'm assuming it's because I need to wait for the lwIP stack
> > > to send the ACK. I'm assuming anyway. If that is the case, how does my
> > > thread know when the stack has sent the ACK to the server and I am at
> > > liberty to send the GET request?
> > >
> > > I hope I've made that clearer. :~)
> > >
> > > I'm probably doing naive things because I'm trying to learn a lot of
> > > stuff at the moment!
> > >
> > > On 13/11/14 13:09, Simon Goldschmidt wrote:
> > > > Robert Wood wrote:
> > > >> If I establish a connection from the board to the desktop and do not
> > > >> send a GET request, then lwIP does the SYN, SYN ACK, ACK handshake
> > just
> > > >> fine.
> > > >>
> > > >> If I add the [potentially incorrect] GET request, the SYNN is
> > sent, the
> > > >> SYN ACK is received, but my board running lwIP does not send the
> > ACK out
> > > >> to the desktop.
> > > >
> > > > Does it piggy-back the ACK on your GET request or is the GET request
> > > not even sent out? I'd expect to see the GET request along with the
> > > handshake-ACK.Then, the webserver will eventually time out waiting for
> > > the double-CRLF.
> > > >
> > > > However, if lwIP does not send ANYTHING after receiving the SYN-ACK,
> > > there's something wrong... :-/
> > > >
> > > > Simon
> > > >
> > > > _______________________________________________
> > > > lwip-users mailing list
> > > > address@hidden
> > > >
https://lists.nongnu.org/mailman/listinfo/lwip-users
> > > >
> > >
> > > _______________________________________________
> > > lwip-users mailing list
> > > address@hidden
> > >
https://lists.nongnu.org/mailman/listinfo/lwip-users
> > >
> > >
> > > _______________________________________________
> > > lwip-users mailing list
> > > address@hidden
> > >
https://lists.nongnu.org/mailman/listinfo/lwip-users
> > >
> >
> > _______________________________________________
> > lwip-users mailing list
> > address@hidden
> >
https://lists.nongnu.org/mailman/listinfo/lwip-users
> >
> >
> > _______________________________________________
> > lwip-users mailing list
> > address@hidden
> >
https://lists.nongnu.org/mailman/listinfo/lwip-users
> >
> _______________________________________________
> lwip-users mailing list
> address@hidden
>
https://lists.nongnu.org/mailman/listinfo/lwip-users
>
>
> _______________________________________________
> lwip-users mailing list
> address@hidden
>
https://lists.nongnu.org/mailman/listinfo/lwip-users
>
_______________________________________________
lwip-users mailing list
address@hidden
https://lists.nongnu.org/mailman/listinfo/lwip-users