*getsockopt*, of all things? [LWN.net]

getsockopt, of all things?

Posted Jul 2, 2009 18:05 UTC (Thu) by quotemstr (subscriber, #45331)
In reply to: *getsockopt*, of all things? by RobSeace
Parent article: The fanotify API

giving the filename and letting the app do its own open

Racetastic, yes?

select()/poll() gets kluged up to falsely indicate readability

Well, to be fair, select even on ordinary objects doesn't indicate readability. It's more like "it might have been readable sometime in the recent past, if you're lucky". That's why you always call select() on non-blocking sockets, and why you always prepare to get EAGAIN even after select() reports a file descriptor to be readable.

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getsockopt, of all things?

Posted Jul 2, 2009 18:41 UTC (Thu) by RobSeace (subscriber, #4435) [Link]

Yeah, but this sounds even worse than that, since it was never truly readable at all, but merely has a sockopt ready to be gotten... *shrug* It just sounds like an ugly kluge to me...

How about just treating the socket as if it were a listening socket, and use accept() to return the FD (and fill the other related necessary info into the returned client sockaddr)? Then, readability on the listener fits the already established model for normal listening sockets, to indicate a new connection to accept, and no need for any klugey FD passing behavior... Of course, returning a non-socket FD from accept() is probably just as ugly a kluge, I suppose... *shrug*