LINUX_IGNPAR
bts->c_iflag |= cvtto_bsd_mask(lt->c_iflag, LINUX_IGNPAR, IGNPAR);
lt->c_iflag |= cvtto_linux_mask(bts->c_iflag, IGNPAR, LINUX_IGNPAR);
bts->c_iflag |= cvtto_bsd_mask(lts->c_iflag, LINUX_IGNPAR, IGNPAR);
lts->c_iflag |= cvtto_linux_mask(bts->c_iflag, IGNPAR, LINUX_IGNPAR);