On Thu, Oct 18, 2012, at 01:25 PM, M Pulis wrote: > Thanks! > > Not using anything low level... hence the surprise.... we actually use > it to determine if our login url is reachable; if not we work > "offline". I'll take a deeper look at what we are doing there.
You can't use Reachability to determine if a URL is reachable. The concept of a URL exists at a much higher level than Reachability operates at. Reachability determines if you have a route to a host at a hostname. That means it asks the system to resolve the hostname if necessary, then consults the routing table to determine if it has a rule to route packets to that host out of the device. It tells you nothing about whether the packets would actually make it there once they've left your device, or if they did whether they could be used to form form a working higher-level connection like HTTP. If you want to determine whether you can connect to a server on a TCP socket, the only thing you can do is attempt the connection. If you want to determine whether you can access a resource over HTTP, the only thing you can do is attempt to access the resource. The only thing Reachability is good for is an early test to see if the device knows it can't possibly communicate with a host because it can't route packets to it. If this is the case, it also gives you a way to be notified when circumstances change and you should try again. --Kyle Sluder _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
