JF_W_ASYNCNOTIFY
j->flags |= JF_W_ASYNCNOTIFY;
int oldf = j->flags & (JF_WAITING|JF_W_ASYNCNOTIFY);
j->flags &= ~(JF_WAITING|JF_W_ASYNCNOTIFY);
j->flags &= ~(JF_WAITING|JF_W_ASYNCNOTIFY);
j->flags &= ~(JF_WAITING|JF_W_ASYNCNOTIFY);
&& (j->flags & (JF_WAITING|JF_W_ASYNCNOTIFY)) != JF_WAITING)