As regular readers are aware, I enjoy spending time logged in to a few personal favorites of the myriad telnet bulletin board systems that are presently online and serving as discussion communities for their users. As often as I can, I use one of my vintage systems to “dial” in and read the latest gossip rather than a modern Mac or PC. I use serial-to-WiFi bridge devices to make the process simple and as clutter-free as possible.
Another “modern day” (if you can call it that) use of these vintage systems I like to engage in is keeping an Internet Relay Chat (IRC) instance open on this or that system to glance at across the room and occasionally wheel my chair over and chat a bit on said system. (I hope you didn’t learn about IRC on TV…) This pursuit is less well served by the aforementioned serial-to-WiFi bridges given that many of the systems on my desks lack a proper IRC client. If I want to use such systems to IRC, the best way to go, from my perspective, is to telnet into my always-on desktop Mac and launch my go-to IRC client, the terminal-based irssi, which works quite well as accessed from a remote VT100 terminal. And, nearly all of the systems in question have VT100 emulation supported by a several software terminal emulator programs such as ProTerm on my favorite vintage IRC system, the Apple IIe to my left.
For years (and on many different systems) I would achieve this by utilizing a USB-to-serial adapter on the Mac and running a serial cable from the vintage system in question to said adapter on the Mac. But it was a cumbersome process. And, several OS updates ago Apple redid the USB stack in macOS and rendered the adapters I had on-hand inoperable. To get around this I setup a Raspberry Pi connected via WiFi to my network, specifically to serve as the host system for the remote terminal, as it maintained support for my adapters — it worked (video), but it was a configuration I was never really happy with.
So, I headed to the Apple II Infinitum Slack channel and asked if it was possible to setup a listener on the desktop Mac to allow a vintage system equipped with a serial-to-WiFi adapter to “dial in” to the Mac and be granted a wireless terminal connection. It turned out, it was.
I learned that in a few simple steps you can setup a listener macOS daemon that will allow an incoming telnet connection to a specified port and present a shell session with a login prompt where you can login and execute terminal commands. When I do so, I’m usually there to launch irssi and connect to an IRC server, but other commands work nicely, such as the system monitor top, if you want to keep an eye on how things are doing when fullscreen apps are hogging the displays. (Another nice terminal-based IRC client is WeeChat, by the way.)
I currently have this arrangement up and running on my 2022 Mac Studio (M1 Max) but I originally set this up on the 2017 5K iMac (Intel Core i5) — it will work on either Apple Silicon or Intel-based systems. Here’s how to do it.
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