Function _connect

dns/query.py:1193–1201

(s, address, expiration)

def _connect(s, address, expiration):
    err = s.connect_ex(address)
    if err == 0:
        return
    if err in (errno.EINPROGRESS, errno.EWOULDBLOCK, errno.EALREADY):
        _wait_for_writable(s, expiration)
        err = s.getsockopt(socket.SOL_SOCKET, socket.SO_ERROR)
    if err != 0:
        raise OSError(err, os.strerror(err))


def tcp(