Re: disk-based fds in select/poll

[Alan Cox]

> Ok, so while knowing about select "lying" about readability of a file
> fd, if I would stick a file fd in my select-based loop anyway, but would

You could fix select to return when the page was cachied and return EWOULDBLOCK
on reads if the page was not present to be honest. I don't think that would
actually break any apps, and the specs seem to allow it

> only try to read a bit at a time (say, 4K or 8K) would trigger
> readahead, yet finish quickly enough that I can get back to processing
> other fds in my select loop?

Probably

> Wouldn't that cause too many syscalls to be done? Or if this is actually
> the way to go without an actual thread, how should I go determining an
> optimal block size?

fs block size I suspect or small multiple thereof