* origin/ds:
ds: stop caring about event flags set by epoll/poll/kqueue
ds: do not distinguish between POLLHUP and POLLERR
ds: remove read method, here, too
nntp: use sysread to append to existing buffer
ds: remove steal_socket method
ds: remove {fd} field
ds: reduce Errno imports and drop ->close reason
ds: cleanup Errno imports and favor constant comparisons
ds: simplify write buffer accounting