Re: [PATCH] char nvtty: Network Virtual Terminal support

[Rodolfo Giometti <giometti@enneenne.com>]

On Mon, Jan 03, 2011 at 05:14:52PM +0000, Alan Cox wrote:
> > By using these devices and a proper compatible server (not included
> > here but you can use sredird) you can get access to a remote tty
> > device as the tty device itself was conneted with your local host.
> > All data and settings are sent and received through the network.
> 
> Interesting but would it not be better to keep all the network stuff in
> user space given that most sane environments will have crypto on them ?

Yes, but in most cases this is used on not-crypted connections (as far
as I know there are no crypted server for this protocol yet), however
we can easily get a crypted connection by connecting with localhost
and then using a program like cryptcat for the crypto stuff.

> It's also a less than ideal protocol in that it can't represent some of
> the things termios can, nor can it report arbitary speeds properly.

I see, but it is widely used and also it can be enhanced to better fit
termios capabilities.

However by using this protocol "as is" we can do several useful
things! :)

> Is there a reason it couldn't use pty/tty pairs either as is or tweaked
> to better report termios changes and allow modem line reporting ?

This is the solution that cyclades-serial-client uses (the userland
program where my patch is derived from) but as far as I know pty/tty
pairs cannot be used to report termios settings but only data... is
that right? =:-o

Ciao,

Rodolfo

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