LINUX_FLUSHO
bts->c_lflag |= cvtto_bsd_mask(lt->c_lflag, LINUX_FLUSHO, FLUSHO);
lt->c_lflag |= cvtto_linux_mask(bts->c_lflag, FLUSHO, LINUX_FLUSHO);
bts->c_lflag |= cvtto_bsd_mask(lts->c_lflag, LINUX_FLUSHO, FLUSHO);
lts->c_lflag |= cvtto_linux_mask(bts->c_lflag, FLUSHO, LINUX_FLUSHO);