TicTacToe example does not give a 'query response' to browser discovery

In the MDNS probe, there are queries and answers. If you are queried and the response is in the answer section (in this case it is), you don't have to respond. That is why the TicTacToe server doesn't respond to the query.

The client doesn't list the game, though, even though it has it in the answer section of the probe.

The client adds and removes the game from the table view on discovery.

Tracing the table view delegate

func tableView(_ tableView: NSTableView, viewFor tableColumn: NSTableColumn?, row: Int){}

the table view loads the game name, then unloads it immediately.

So, now the question is why does the game name get removed?

Do you mean, why does the game name get removed after a certain amount of inactivity, or just from the tableviews

| So, now the question is why does the game name get removed?

Matt Eaton

DTS Engineering, CoreOS

meaton3 at apple.com

The issue is with NWBrowser and how it deals with cached DNS services.

If the service (the game) isn't cached, then there is only a query in the DNS probe. The service gives a query response. NWBrowser calls browseResultsChangedHandler() once, with the service.

If the service is cached, there is a query and answer in the DNS probe. The service doesn't give a query response because the service name is in the answer section of the probe. NWBrowser calls browseResultsChangedHandler() once, with the service from the cache, and then within 100 ms a second time, with no services. This is not always true in TicTacToe, but sometimes is. In a test program that I wrote, it is always true.

If I accumulate the services rather than clearing 'results' every time (which TicTacToe does) then I have the service, and I can connect to it.

The question is whether browseResultsChangedHandler() is calling with the complete list of services every time. From the documentation, it is 'updates', so I guess it is not the complete list, just additions. If that is true then TicTacToe shouldn't be clearing 'results' every time browseResultsChangedHandler() is called.