I run NetBSD 1.0 and try to use a modem
for ppp and tip connection to a remote site.

pppd and tip block during the open of the /dev/ttyxx

I added O_NONBLOCK to the open options in pppd and
had good results : I can connect to the remote host and ftp etc ...


Now my pbroblems are with silo overflow on /dev/tty01
I know that these problems arrive when the interrupt rate
is to hight.
As my UART haven't fifo buffer, I can suppress the silo overflow pb 
only when I slow down the speed between host and modem to 9600 which is very
low.

The biggest problem is that when a silo overflow occur ppp drivier break
(the only solution have found is to switch off my modem and reboot because
in this case I can't even kill -9  pppd)
I think it's a bug in the driver because, normaly, lost of data must be supported
by ppp.

So my questions are :
Is it normal that I have to mod the pppd (and chat) program or have I a problem
with my com port ?
Is there a other solution ?
Is it known  that silo overflow break the ppp driver ?
Are these problems solved in NetBSD-current ?
 
Thanks in advance 

Thierry Leconte