select.py 文件源码

def register(self, fd, eventmask=_NONE):
            if eventmask is _NONE:
                flags = _EV_READ | _EV_WRITE
            else:
                flags = 0
                if eventmask & POLLIN:
                    flags = _EV_READ
                if eventmask & POLLOUT:
                    flags |= _EV_WRITE
                # If they ask for POLLPRI, we can't support
                # that. Should we raise an error?

            fileno = get_fileno(fd)
            watcher = self.loop.io(fileno, flags)
            watcher.priority = self.loop.MAXPRI
            self.fds[fileno] = watcher