In some quick tests on my system, a syswrite or send of 0 bytes doesn't seem to send any data across the network, which means it won't detect a host that has disappeared (though it will detect a connection that the OS already knows is dead).

Have you tried this and did it work? It would be extremely useful to have some way to probe a connection in this way, and the protocol supports it, but unfortunately the OS doesn't seem to provide a way to access this functionality.

Thanks!


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sgifford's Web page

In reply to Re^2: An IO::Sockets 'test for live connection' question: by sgifford
in thread An IO::Sockets 'test for live connection' question: by jonahgrimm

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