Re: Text based synchronous communication tool for Linux?

In article <vj4jmv$3tpsd$1@dont-email.me>,
Janis Papanagnou  <janis_papanagnou+ng@hotmail.com> wrote:

On 08.12.2024 17:25, Muttley@DastardlyHQ.org wrote:

On Sun, 8 Dec 2024 14:15:48 -0000 (UTC)
John McCue <jmccue@whitedwf.jmcunx.com> wibbled:

Janis Papanagnou <janis_papanagnou+ng@hotmail.com> wrote:
<snip>

>
Some characteristics I'd prefer - not all supported by the 'phone'
utility - are that it's
 * text-oriented (preferably with Unicode support), fast (no GUI)
 * instantly/synchronously exchanging any typed characters
    * optionally: switching modes (instant/character-wise, line-wise)
 * more than two persons can communicate
 * works across distributed [Unix-]systems
>
Is there such a tool (free of charge and open source) available for
Linux? (Or something that comes close?)
>

Slackware comes with a utility called "talk", it is
disabled by default.  It sounds like what you are
looking for.  It allows 2 people to 'text' each other.
>
https://www.slackbook.org/html/basic-network-commands-talk.html

 
talk is an age old unix util that allows people on the same machine to chat.
Even MacOS has it installed.

>
As said, I think the historic DEC/VAX tool worked (also) only
locally; you had to log into the same VMS-system to communicate.
>
I'm actually looking for a tool that works across distributed
[Unix-]systems.
>
I'll look into the tools suggested so far what they provide.

`phone` worked across DECnet, but I don't believe it was ever
extended to work across TCP/IP.

`talk` will work between machines, over TCP/IP, but the way it
works is brittle and doesn't work well over the modern Internet.
In particular, it is de-facto limited to IPv4 and doesn't
play well with firewalls: it involves sending the contents of a
`sockaddr_in` across the network, and using that to set up a
(direct) TCP connection between processes.  One could imagine
building a proxy for it, but to my knowledge no one did so.

- Dan C.