Determining if a client PC has an Internet connection

[Stuart McGraw]

"Cliff Wells" <clifford.wells at comcast.net> wrote in message news:mailman.3499.1095589700.5135.python-list at python.org...
[...snip...]
> As I mentioned in another post, it seems a reasonable solution would be
> to determine the PC's DNS search path and then try those hosts.  If they
> are unreachable then assume the connection is down.  This would seem to
> be reasonably cross-platform (although admittedly, exactly how this is
> done would probably vary across platforms)

I'm not sure this is 100% reliable either.  I have several PCs on a home 
network with a Linux box running a local caching DNS server that is the 
primary (and sole) DNS server for the Windoze boxes..  That server is 
always reachable even when my modem internet connection is down.