<div dir="ltr"><div>This problem goes way back; in Open Cobalt I ended up going through a bunch of adhoc steps and adding a manual config option to try and figure out if I was behind a firewall and what the address of the firewalled interface was.</div><div><br></div><div>Have you considered the temp solution of forking off an ifconfig and parsing out the results? I suspect in many cases, choosing the IP of the default IPv4 or IPv6 interface would get you what you want. <br></div><div><br></div><div>Cheers,</div><div>-- John</div><div><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Mon, Sep 21, 2015 at 1:53 PM, tim Rowledge <span dir="ltr"><<a href="mailto:tim@rowledge.org" target="_blank">tim@rowledge.org</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><br>
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On 21-09-2015, at 1:41 PM, John McIntosh <<a href="mailto:johnmci@smalltalkconsulting.com">johnmci@smalltalkconsulting.com</a>> wrote:<br>
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> The problem with connecting to 8.8.8.8 which is Google's public DNS server is that:<br>
> (a) you might not have access to the internet<br>
> (b) you might be going thru a proxy and it may not be on the school white-list<br>
> (c) tapping port 80 on the dns server likely won't work either.<br>
‘zackly.<br>
<span class=""><br>
tim<br>
--<br>
tim Rowledge; <a href="mailto:tim@rowledge.org">tim@rowledge.org</a>; <a href="http://www.rowledge.org/tim" rel="noreferrer" target="_blank">http://www.rowledge.org/tim</a><br>
</span>Useful random insult:- Has an inferiority complex, but not a very good one.<br>
<br>
<br>
</blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature">John Dougan<br><a href="mailto:jdougan@acm.org" target="_blank">jdougan@acm.org</a></div>
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