Hello Kris, > Basically, I cannot connect to port xxx for sending when I'm already > listening to it...
A socket can send and receive both. UDP Connect is the same as UDP Listen. So you can not do both. The difference is the handling. If you call connect then send, then you send to the addr:port in the properties. LocalAddr:LocalPort are the interface the socket is bound. If you call listen then you bind to the Addr:Port properties. If you call Listen you have to send with SendTo. --- Rgds, Wilfried [TeamICS] http://www.overbyte.be/eng/overbyte/teamics.html http://www.mestdagh.biz Sunday, April 2, 2006, 22:28, Kris Schoofs wrote: >> But that's not a problem is it? Listen, connect, send query, wait x > seconds for responses, stop listen, repeat... > I'm unable to execute the sequence you suggest. > Listen to port xxx : OK > Connect to port xxx : 'winsock.bind failed, error #10048' > So, I'm unable to send the query and that's where it ends... Nobody will > respond. > Basically, I cannot connect to port xxx for sending when I'm already > listening to it... > And my guess is that with the sequence I'm currenlty using... > - Connect to port xxxx : Send query > - Close port xxxx > - Listen to port xxxx > ...There is too much delay between switching from sending to listening > causing me to miss some of the initial UDP packets. > When running tests I can see 3 scenarios.... > Either : > (A) I get no packets at all. =>> Ethereal shows for every response that was sent to me an ICMP that > reports "destination unreachable (Port unreachable)". Apparently the socket > is not yet listening... > Or > (B) I only get some of the packets. Usually the first few of the sequence > are missing (the UPnP device I'm currently using sends back 14 packets in > response to my discovery request). Strangely enough, Ethereal does not > report anymore that the "destination unreachable (Port unreachable)", but > TWSocket also does not make those initial packets available to me. > Or > (C) Sometimes everything works great and I get all packets sent to me (14 in > my test case, as confirmed by Ethereal). > I'm also wondering why sometimes OnDataAvailable is called when listening > but Receive() reports that the received length is -1. > SCENARIO A > - I get nothing back > - Ethereal shows for every response that was sent to me an ICMP that reports > "destination unreachable (Port unreachable)". > ========== > Send UDP : Send via port 1171 > Send UDP : DONE. Close Socket > LISTEN UDP : listening on port 1171 > Listen UDP for 5 seconds : DONE. Close Socket > UDP with ReceiveLength >0 = [00] > UDP with ReceiveLength <1 = [00] > SCENARIO B > - only 11 out of 14 packets > - First 3 packets are missing, see scenario B > ========== > Send UDP : Send via port 1167 > Send UDP : DONE. Close Socket > LISTEN UDP : listening on port 1167 > UDP#01=ReceiveLen=249 > UDP#02=ReceiveLen=283 > UDP#03=ReceiveLen=249 > UDP#04=ReceiveLen=283 > UDP#05=ReceiveLen=261 > UDP#06=ReceiveLen=309 > UDP#07=ReceiveLen=296 > UDP#08=ReceiveLen=313 > UDP#09=ReceiveLen=315 > UDP#10=ReceiveLen=305 > UDP#11=ReceiveLen=305 > > UDP#**=ReceiveLen=-1 > > UDP#**=ReceiveLen=-1 > > UDP#**=ReceiveLen=-1 > > UDP#**=ReceiveLen=-1 > > UDP#**=ReceiveLen=-1 > > UDP#**=ReceiveLen=-1 > > UDP#**=ReceiveLen=-1 > > UDP#**=ReceiveLen=-1 > > UDP#**=ReceiveLen=-1 > > UDP#**=ReceiveLen=-1 > Listen UDP for 5 seconds : DONE. Close Socket > UDP with ReceiveLength >0 = [11] > UDP with ReceiveLength <1 = [10] > SCENARIO C > - I get everything back nicely > ==========Send UDP : Send via port 1166 > Send UDP : DONE. Close Socket > LISTEN UDP : listening on port 1166 > UDP#01=ReceiveLen=232 > UDP#02=ReceiveLen=243 > UDP#03=ReceiveLen=304 > UDP#04=ReceiveLen=249 > UDP#05=ReceiveLen=283 > UDP#06=ReceiveLen=249 > UDP#07=ReceiveLen=283 > UDP#08=ReceiveLen=261 > UDP#09=ReceiveLen=309 > UDP#10=ReceiveLen=296 > UDP#11=ReceiveLen=313 > UDP#12=ReceiveLen=315 > UDP#13=ReceiveLen=305 > UDP#14=ReceiveLen=305 > Listen UDP for 5 seconds : DONE. Close Socket > UDP with ReceiveLength >0 = [14] > UDP with ReceiveLength <1 = [00] > Kris > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On > Behalf Of Angus Robertson - Magenta Systems Ltd > Sent: zondag 2 april 2006 18:56 > To: twsocket@elists.org > Subject: Re: [twsocket] THttpCli and UPnP devices >> However, any subsequent attempts to use that same port for sending the >> UDP packet fail. Only after closing the socket used for listening I >> can use that port for sending a packet. > But that's not a problem is it? Listen, connect, send query, wait x seconds > for responses, stop listen, repeat... > Does Windows not provide an API for UPnP discovery? Certainly Windows > Vista, which I'm currently playing with, has Function Discovery interfaces > that do all this, Vista even found my Linksys wireless access point, mind it > didn't find a proper display adapter and Vista is really painful in VGA. > Angus > -- > To unsubscribe or change your settings for TWSocket mailing list please goto > http://www.elists.org/mailman/listinfo/twsocket > Visit our website at http://www.overbyte.be -- To unsubscribe or change your settings for TWSocket mailing list please goto http://www.elists.org/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
