Best way to check if there is internet?

[Cameron Simpson]

On 08Feb2022 06:51, Chris Angelico <rosuav at gmail.com> wrote:
>Some day, we'll have people on Mars. They won't have TCP connections -
>at least, not unless servers start supporting connection timeouts
>measured in minutes or hours - but it wouldn't surprise me if some
>sort of caching proxy system is deployed.

The TCP ESTABLISHED state has no timeouts at all (though intemediate 
stateful things can get bored).  The setup/teardown do though :-) But 
they can be proxied. Our previous satellite modem proxied TCP locally 
and ran a more-suitable-satellite protocol from the modem to the 
downstation, where it became TCP again and went on its way.

Cheers,
Cameron Simpson <cs at cskk.id.au>