Following pspautotests net/inet/polledge:
- poll reports only what was asked for, and never POLLHUP or POLLERR,
even for a peer that closed or reset the connection.
- select with a closed descriptor in a set fails with EBADF and leaves
the sets alone. It used to skip it.
The host side now uses poll() outside Windows, where select() can't take
a descriptor numbered FD_SETSIZE or above and FD_SET wrote past the
fd_set. macOS reports a peer that closed as POLLHUP with POLLPRI, and
the POLLPRI is ignored, as its select() shows nothing for it. Winsock's
select() has no such limit, but takes only 64 sockets a set, so it's
called on groups of 64, and poll is no longer cut short at 64 entries
there. A failing poll sets the host's errno rather than EINTR.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
