Re: term & user space console

[Roland McGrath]

> The obvious difference is what happens to data that is available in the
> underlying file while CREAD is turned off.  Both, devio and ptyio discard
> such data, while in your design it would be delayed until CREAD is enabled.
> I couldn't find out what is the right thing (the standards just say "enable
> receiver" about CREAD).

I think you should discard data when CREAD is clear.  I also think a change
in CREAD state should be passed down with a tioctl call as for modem
control bits.  When (eventually, with new interfaces) this is passed all
the way down to the device driver, some devices can disable the receiver in
hardware so no data interrupts are generated.

> Mmmh.  There probably is a way, but I am not aware of it.  Note that I was
> thinking about using io_select, not the glibc select function.

Interruptible RPCs are interruptible at the RPC level.