<html> <head> <style></style></head> <body class='hmmessage'><div dir='ltr'>Hey guys,<div><br></div><div>Thanks a lot for your quick answers!</div><div><br></div><div>My ping method now:</div><div><br></div><div><div>(define (ping hostname port-no personalip)</div><div> (define t (thread</div><div> (lambda ()</div><div> (with-handlers ((exn:fail:network? (lambda (x) (begin (displayln (string-append hostname ":" (number->string port-no) " NOOOOOOOOOO")) #f))));(displayln (exn-message x)))))</div><div> (define-values (in out) (tcp-connect hostname port-no))</div><div> (write "'ping" out)</div><div> (write personalip out)</div><div> (flush-output out)</div><div> (display (string-append hostname ":" (number->string port-no) " "))</div><div> (displayln (read in))</div><div> (close-input-port in)</div><div> (close-output-port out)</div><div> #t))))</div><div> (sync/timeout 0.01 t)</div><div> (kill-thread t))</div><div><br></div><div>+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++</div><div><br></div><div>This is the result when I do a multicast from 192.168.1.0 to 192.168.1.200. ( a lot of these don't exist and that's why tcp-connect was taking ages to throw an error.) Those returning a NOOOOO are existing network nodes where no server is running. Pong is the answer from the <span style="font-size: 12pt;">server running on my</span><span style="font-size: 12pt;"> laptop.</span></div><div><br></div><div><div>> (multicast-ping "192.168.1.100" 8080 0 200)</div><div>192.168.1.0:8080 NOOOOOOOOOO</div><div>192.168.1.105:8080 NOOOOOOOOOO</div><div>192.168.1.108:8080 pong</div><div>-------------------</div><div>Multicast finished!</div></div><div><br></div><div>+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++</div><div><br></div><div><br></div><div>It's still test-code but it's working fine now, maybe the timout time is too small but now it works well!</div><div><br></div><div>Greetings,</div><div>Nicolas</div><br><div><hr id="stopSpelling">Subject: Re: [racket-dev] Implementation question<br>From: matthias@ccs.neu.edu<br>Date: Sat, 19 Apr 2014 09:25:27 -0400<br>CC: nicocarraggi@hotmail.com; dev@racket-lang.org<br>To: laurent.orseau@gmail.com<br><br><div><br></div><div>Let me recommend events instead: </div><div><br></div><div><div>#lang racket</div><div><br></div><div>;; Nat -> Void </div><div>;; wait for t seconds before connecting to <a href="http://google.com" target="_blank">google.com</a>, then stop</div><div>(define (do-work t)</div><div> (thread</div><div> (lambda ()</div><div> (with-handlers ((exn:fail:network? (lambda (x) (displayln (exn-message x)))))</div><div> (sleep t)</div><div> (define-values (in out) (tcp-connect "<a href="http://google.com" target="_blank">google.com</a>" 80)) </div><div> 'done))))</div><div><br></div><div>;; returns #f if 3 seconds pass w/o the thread shutting down </div><div>(sync/timeout 3 (do-work (random 6)))</div></div><div><br></div><div><br></div><br><div><div>On Apr 19, 2014, at 8:34 AM, Laurent wrote:</div><br class="ecxApple-interchange-newline"><blockquote><div dir="ltr"><div><div>One simpler possibility is to use `tcp-connect/enable-break` and run a timer in parallel to break it after a shorter delay.<br></div>For example:<br><br>(define-values (in out) (values #f #f))<br><br> (define connect-thread<br> (thread<br> (ë()(set!-values (in out) <br> (tcp-connect "<a href="http://www.google.com/" target="_blank">www.google.com</a>" 80)))))<br><br>(sleep 3)<br>(unless in<br> (displayln "Connection not established. Breaking thread.")<br> (break-thread connect-thread))<br><br></div><div>The timer can also be place into its own thread if you need to set up several connections in parallel.<br><br></div><div>Hope this helps,</div>Laurent<br></div><div class="ecxgmail_extra"> <br><br><div class="ecxgmail_quote">On Thu, Apr 17, 2014 at 6:48 PM, nicolas carraggi <span dir="ltr"><<a href="mailto:nicocarraggi@hotmail.com" target="_blank">nicocarraggi@hotmail.com</a>></span> wrote:<br><blockquote class="ecxgmail_quote" style="border-left:1px #ccc solid;padding-left:1ex;"> <div><div dir="ltr">Hello,<div><br></div><div>I am actually using "Racket/tcp" for a project in Racket.</div><div>I'm creating a peer-to-peer network but now I encountered a small problem.</div><div>For a multicast I want to connect with each server on the same network. </div> <div>For this I use "tcp-connect", but when i try to connect to an ip address which is not hosting a server, throwing the error only happens after more than 1 minute. So I would like to use a modified "tcp-connect" with a smaller time-out.</div> <div><br></div><div>Where can I find the implementation of "tcp-connect"?</div><div><br></div><div>I already found "tcp.rkt" but there it gets the "tcp-connect" method from "'#%network" but I can't find this one...</div> <div><br></div><div>Greetings!</div><span class="ecxHOEnZb"><font color="#888888"><div>Nicolas</div> </font></span></div></div> <br>_________________________<br> Racket Developers list:<br> <a href="http://lists.racket-lang.org/dev" target="_blank">http://lists.racket-lang.org/dev</a><br> <br></blockquote></div><br></div> _________________________<br> Racket Developers list:<br> <a href="http://lists.racket-lang.org/dev" target="_blank">http://lists.racket-lang.org/dev</a><br></blockquote></div><br></div></div> </div></body> </html>