Davide Libenzi wrote:
POLLHUP
The device has been disconnected. This event and POLLOUT are
mutually-exclusive; a stream can never be writable if a hangup has
occurred. However, this event and POLLIN, POLLRDNORM, POLLRDBAND,
or POLLPRI are not mutually-exclusive.
which doesn't quite say that POLLHUP may be signalled when
there's still bunches of data to read, but it comes close.
If you think about it, it comes fairly simple. Suppose you have:
PEER PEER
send 10k
recv 2k
send FIN
POLLHUP
(8k pending here)
Yes, it's perfectly reasonable. It's just not what I was expecting.
Just goes to show: I never understand POLLHUP (assuming this
is also the way POLLHUP behaves with poll()). I just always assumed
it was just like EOF.
BTW I finally posted my 2nd try at a userspace wrapper that lets programs
use /dev/epoll, sys_epoll, and sigio interchangably; it's
at http://kegel.com/rn/ and is significantly simpler than my
old Poller, since it doesn't try to simulate level-triggering at all
with sigio.
- Dan
--
Dan Kegel
http://www.kegel.com
http://counter.li.org/cgi-bin/runscript/display-person.cgi?user=78045
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