diff --git a/ttynvt.c b/ttynvt.c
index feeb7ec..df8b1ed 100644
--- a/ttynvt.c
+++ b/ttynvt.c
@@ -61,16 +61,17 @@ typedef struct {
 
     struct pollfd   fds[3];
 
-    struct termios  tio;
-    unsigned char   mcr;
-
     char            net_buf[NET_BUF_SIZE];
     size_t          net_cnt;
     char            tmp_buf[TMP_BUF_SIZE];
 
+    struct termios  tio;
+    int             cmcr;
     int             epipe;
-    volatile sig_atomic_t error;
-    volatile sig_atomic_t pollin;
+
+    volatile int    smcr;
+    volatile int    error;
+    volatile int    pollin;
 
     tn_ctx_t       *tn;
 } ttynvt_t;
@@ -200,12 +201,7 @@ static void    *_read_net(void *arg)
             else
                 break;
         }
-        else if (tty->fds[FD_NET].revents & (POLLERR | POLLHUP | POLLNVAL))
-        {
-            _log(LOG_ERR, "net io error\n");
-            break;
-        }
-        else if (tty->fds[FD_NET].revents & POLLIN)
+        if (tty->fds[FD_NET].revents & POLLIN)
         {
             res = read(tty->fds[FD_NET].fd, tty->net_buf + tty->net_cnt,
                        NET_BUF_SIZE - tty->net_cnt);
@@ -334,25 +330,24 @@ static int _srv_read(void *cctx, int timeout)
 static void _modem_status_cb(void *cctx, int status)
 {
     ttynvt_t       *tty = cctx;
+    int            mcr = 0;
 
     DBG("MCR: DSR=%c CTS=%c RI=%c CD=%c\n",
         status & TNS_STATE_DSR ? '1' : '0',
         status & TNS_STATE_CTS ? '1' : '0',
         status & TNS_STATE_RI ? '1' : '0', status & TNS_STATE_CD ? '1' : '0');
 
-    pthread_mutex_lock(&tty->tty_lock);
-
-    tty->mcr &= ~(TIOCM_CD | TIOCM_RI | TIOCM_CTS | TIOCM_DSR);
-
     if (status & TNS_STATE_CD)
-        tty->mcr |= TIOCM_CD;
+        mcr |= TIOCM_CD;
     if (status & TNS_STATE_RI)
-        tty->mcr |= TIOCM_RI;
+        mcr |= TIOCM_RI;
     if (status & TNS_STATE_CTS)
-        tty->mcr |= TIOCM_CTS;
+        mcr |= TIOCM_CTS;
     if (status & TNS_STATE_DSR)
-        tty->mcr |= TIOCM_DSR;
+        mcr |= TIOCM_DSR;
 
+    pthread_mutex_lock(&tty->tty_lock);
+    tty->smcr = mcr;
     pthread_mutex_unlock(&tty->tty_lock);
 }
 
@@ -615,6 +610,7 @@ ttynvt_ioctl(fuse_req_t req, int cmd, void *arg,
     ttynvt_t       *tty = (ttynvt_t *) (uintptr_t) info->fh;
     struct winsize  ws;
     unsigned int    tiocm = 0;
+    int             mcr;
     static struct termios tio = {
         .c_cflag = B115200 | CS8 | PARODD | CREAD | CLOCAL,
     };
@@ -677,15 +673,12 @@ ttynvt_ioctl(fuse_req_t req, int cmd, void *arg,
             if (tio.c_cflag & CRTSCTS)
                 telnet_rfc2217_ctl(tty->tn, TNS_CTL_CTSRTS);
 
-#if 1
-            pthread_mutex_lock(&tty->tty_lock);
-            if (!(tty->mcr & TIOCM_DTR) && speed != B0)
+            if (!(tty->cmcr & TIOCM_DTR) && speed != B0)
             {
-                tty->mcr |= TIOCM_DTR;
+                tty->cmcr |= TIOCM_DTR;
                 telnet_rfc2217_ctl(tty->tn, TNS_CTL_DTR_ON);
             }
-            pthread_mutex_unlock(&tty->tty_lock);
-#endif
+
             DBG("termios: %u%c%u%u %cCTSRTS %cCREAD %cHUPCL %cCLOCAL\n",
                 baudrate(speed), pstr[par], csize, sb,
                 tio.c_cflag & CRTSCTS ? '+' : '-',
@@ -747,63 +740,58 @@ ttynvt_ioctl(fuse_req_t req, int cmd, void *arg,
     case TIOCMGET:
         CHECK_BUF_OUT(sizeof(int));
         pthread_mutex_lock(&tty->tty_lock);
-        fuse_reply_ioctl(req, 0, &tty->mcr, sizeof(int));
+        mcr = tty->cmcr | tty->smcr;
         pthread_mutex_unlock(&tty->tty_lock);
+        fuse_reply_ioctl(req, 0, &mcr, sizeof(int));
         break;
     case TIOCMBIS:
         CHECK_BUF_IN(sizeof(int));
         tiocm = *(unsigned int *)in_buf;
         fuse_reply_ioctl(req, 0, 0, 0);
         DBG("%s: cmd=%s tiocm=%#x\n", __func__, _ioctl_name(cmd), tiocm);
-        pthread_mutex_lock(&tty->tty_lock);
         if (tiocm & TIOCM_RTS)
         {
-            tty->mcr |= TIOCM_RTS;
+            tty->cmcr |= TIOCM_RTS;
             telnet_rfc2217_ctl(tty->tn, TNS_CTL_RTS_ON);
         }
         if (tiocm & TIOCM_DTR)
         {
-            tty->mcr |= TIOCM_DTR;
+            tty->cmcr |= TIOCM_DTR;
             telnet_rfc2217_ctl(tty->tn, TNS_CTL_DTR_ON);
         }
-        pthread_mutex_unlock(&tty->tty_lock);
         goto show_mctl;
     case TIOCMBIC:
         CHECK_BUF_IN(sizeof(int));
         tiocm = *(unsigned int *)in_buf;
         fuse_reply_ioctl(req, 0, 0, 0);
         DBG("%s: cmd=%s tiocm=%#x\n", __func__, _ioctl_name(cmd), tiocm);
-        pthread_mutex_lock(&tty->tty_lock);
         if (tiocm & TIOCM_RTS)
         {
-            tty->mcr &= ~TIOCM_RTS;
+            tty->cmcr &= ~TIOCM_RTS;
             telnet_rfc2217_ctl(tty->tn, TNS_CTL_RTS_OFF);
         }
         if (tiocm & TIOCM_DTR)
         {
-            tty->mcr &= ~TIOCM_DTR;
+            tty->cmcr &= ~TIOCM_DTR;
             telnet_rfc2217_ctl(tty->tn, TNS_CTL_DTR_OFF);
         }
-        pthread_mutex_unlock(&tty->tty_lock);
         goto show_mctl;
     case TIOCMSET:
         CHECK_BUF_IN(sizeof(int));
         tiocm = *(unsigned int *)in_buf;
         fuse_reply_ioctl(req, 0, 0, 0);
         DBG("%s: cmd=%s tiocm=%#x\n", __func__, _ioctl_name(cmd), tiocm);
-        pthread_mutex_lock(&tty->tty_lock);
-        tty->mcr &= ~(TIOCM_RTS | TIOCM_DTR);
-        tty->mcr |= tiocm & (TIOCM_RTS | TIOCM_DTR);
+        tty->cmcr &= ~(TIOCM_RTS | TIOCM_DTR);
+        tty->cmcr |= tiocm & (TIOCM_RTS | TIOCM_DTR);
         telnet_rfc2217_ctl(tty->tn, (tiocm & TIOCM_DTR) ?
                            TNS_CTL_DTR_ON : TNS_CTL_DTR_OFF);
         telnet_rfc2217_ctl(tty->tn, (tiocm & TIOCM_RTS) ?
                            TNS_CTL_RTS_ON : TNS_CTL_RTS_OFF);
-        pthread_mutex_unlock(&tty->tty_lock);
         goto show_mctl;
       show_mctl:
         DBG("MCR: DTR=%c RTS=%c\n",
-            tty->mcr & TIOCM_DTR ? '1' : '0',
-            tty->mcr & TIOCM_RTS ? '1' : '0');
+            tty->cmcr & TIOCM_DTR ? '1' : '0',
+            tty->cmcr & TIOCM_RTS ? '1' : '0');
         break;
     case TCSBRK:
         fuse_reply_ioctl(req, 0, 0, 0);