It's taken me a while to get around to replying to this since I had to upgrade
to a newer current.  Now I'm running a current supped on around July 31st...

I said:

> If you do a "cu -l /dev/tty01" where tty01 has had the COM_SW_CLOCAL bit set
> by ttyflags, the open succeeds.  But when you try to type anything you get
> 
> 	cu: write: input/output error

... to which Martin replied:

> I don't know what version you are using, but with -current from 26 July
> it works fine for me on i386. My /etc/ttys line is:
> 
> # modem under control of mgetty:
> tty01 "/usr/libexec/mgetty tty01"	vt100  off local rtscts

I still have exactly the same problem as before with this newer version of
current.  Perhaps mgetty is doing something to the state of the line to cause
"cu" to not get the error.  I'm not sure if the 1.05 version of "cu" fixes
this problem.

Duncan

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