SS_RCVATMARK
so->so_state &= ~SS_RCVATMARK;
so->so_state |= SS_RCVATMARK;
*(int *)data = (so->so_state&SS_RCVATMARK) != 0;
so->so_state &= ~SS_RCVATMARK;
so->so_state |= SS_RCVATMARK;
so->so_state &= ~SS_RCVATMARK;
so->so_state |= SS_RCVATMARK;
so->so_state |= SS_RCVATMARK;
(so->so_state & SS_RCVATMARK) == 0) ||