UMSR_DCD
com->c_msr = UMSR_DSR | UMSR_CTS | UMSR_DCD;
msr = com->c_msr & ~(UMSR_DCD | UMSR_DSR | UMSR_RI);
msr |= UMSR_DCD;
if (ISSET(combits, UMSR_DCD))
if (ISSET((msr ^ old_msr), UMSR_DCD)) {
(sc->sc_msr & UMSR_DCD) ?
(*tp->t_linesw->l_modem)(tp, ISSET(msr, UMSR_DCD));
sc->sc_msr = UMSR_DCD;
(void) (*tp->t_linesw->l_modem)(tp, ISSET(sc->sc_msr, UMSR_DCD));
if ((sc->sc_umodem.sc_msr & UMSR_DCD) == 0)
sc->sc_umodem.sc_msr |= UMSR_DCD;
sc->sc_msr |= UMSR_DCD;
sc->sc_msr |= UMSR_DCD;
sc->sc_msr |= UMSR_DCD;
*msr |= ISSET(mdmsts, SLSA_MDMSTS_DCD) ? UMSR_DCD : 0;
SET(sc->sc_msr, UMSR_DCD);