Re: [screen-devel] using screen for connecting two machines via serial port

[david kerns]

Typically, you run getty on one computer (the host), then screen (or some other terminal emulator) on the second.

getty will prompt you for a login/password and then spawn a shell.

I suppose you could just spawn a shell directly (from systemctl), but that is, obviously, insecure.

Ultimately, what you're seeing is an issue with canonical processing. The "host" of the connection usually "echos" back each character sent to it.

On Tue, May 24, 2022 at 5:57 PM Elmar Stellnberger via screen-devel <screen-devel@gnu.org> wrote:

Dear maintainers of screen

   Today I wanted to connect two machines using screen:
machine1> screen /dev/ttyS0
machine2> screen /dev/ttyUSB0

   The problem about it is that \n does not go to the beginning of a new
line but merely one line below without carriage return. I have tried to
set onlcr with stty but that does not help. Also I have played with
TERM=putty and screen.putty but could not resolve the issue.

   I have discovered the same issue with
machine1> screen /dev/ttyS0
machine2> echo hugo >/dev/ttyUSB0

   The goal would of course be to run bash on one computer and screen on
the other:
machine1> screen /dev/ttyS0
machine2> TERM=screen.putty bash </dev/ttyUSB0 >/dev/ttyUSB0
2>/dev/ttyUSB0 & echo $!

   Same problem here: '\n' does not do an additional carriage return as
required.

Anyone here who can help me?


Elmar Stellnberger