In the cloonix software, openpty is used to get a tty pair master/slave,
then on the uml  linux start line, this is added for ttyS0:

Then whatever is written on the master fd gets into the ttyS0 of the
uml machine and the other way for read.

With this solution, you have to write a little process that runs in your
host, but then you can also control the data passing through.

On Thu, Jun 25, 2009 at 09:46:44PM -0400, lanas wrote:
>   I would like to connect to a UML as if with a plain serial port.  No
> protocol, no telnet, no nothng, simply like a serial port, at any
> speed, 8N1. I type 'A' in the host's minicom and the minicom in the UML
> receives 'A'.
>   How would I launch the UML to get that type of connectivity ?  What
> would be the device inside the UML ?  What would be the device on the
> host for minicom to use ?  And is there any special config or mknod to
> be done in both the host and the UML ?
> Thanks for any suggestions/hints/ideas.

Untested, but use a pts/tty pair.  'con2=pts' on the command line, see
what pts device it got (you probably need to run minicom inside UML in
order to make it open the host device), attach minicom on the host to
the corresponding tty, and they should communicate.

Alternatively, you may need to reverse the pty/tty, not sure.  Run
minicom on the host on /dev/ptmx, see what device it got, run UML with


Work email - jdike at linux dot intel dot com

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