Yes, trying to figure out WHY the connection failed is trickier. I think you are right that Safari pings an IP (to exclude DNS problems) and then looks at the response. A ping that has no route will report something like Destination Unreachable as opposed to timeout. On my Apple terminal, if I ping a bogus DNS name, I get cannot resolve <hostname>: unknown host. If I ping a bogus IP, I get a timeout. If I disable all network adapters I get a timeout AND sendto: No route to host. Windows probably does something similar.
I suppose you could simply ping through a shell and then peruse the responses. Bob S > On Mar 2, 2018, at 10:09 , Graham Samuel via use-livecode > <use-livecode@lists.runrev.com> wrote: > > Bob of course you’re right - in my particular case, anyway, I just want to > know if I can access me chosen server or not. > > But one could certainly imagine programs that would want to know if they were > wasting their time offering their users a broader internet access - I mean > any program that allows the user to specify addresses (like a browser does) > would want more of an “is there or isn’t there?” approach. On my Mac, the > Apple browser Safari can announce “you are not connected to the internet”. > Maybe it just pings a trusted source and waits for a reasonable time for the > reaction. > > Anyway what I noticed in my little experiment was that the reaction of the > script when the internet wasn’t available was very rapid (certainly less than > half a second), which means that just trying to get the file and then looking > for an error response would probably be OK for a human user, since there is > no prolonged wait. > > As you see, I am reluctant to do anything that’s at all complicated! > > Graham _______________________________________________ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
