Some time ago I began a search for a decent note-taking tool that I could carry around with me. For many years I was a devotee of the notes.txt file on my desktop, constantly open in a text editor so I could add and refer to it as necessary. When that ceased to scale I turned to software that replicated the legions of sticky notes on my desks at work and home, such as Tomboy. And that worked well enough for a while, but when I started relying upon my mobile more and more for things it too stopped being as useful as I wanted it to be. For about a year I turned to Simplenote, which is pretty much what it says on the tin: It's a note-taking system with a nice web interface, applications on all of the platforms that I use regularly, and even a command line utility which I used to back up my notes a couple of times a day. However, Simplenote is a centralized service and there is always a risk that it could go away at any time. At the very least, the switchover to the Simperium API could have caused problems in the near term for me, and I have enough on my plate these days that I didn't feel like fighting that particular war. So, the search for a replacement that relied more upon my own infrastructure than someone else's began.
20170107: It's not "group name" it's "Group ID." I don't know how to find that yet.
The communications program Signal by Open Whisper Systems is unique in several respects. Firstly, its barrier to entry is minimal. You can search for it in the Google Play online store or Apple iOS appstore and it's waiting there for you at no cost. Second, it's designed for security by default, i.e., you don't have to mess around with it to make it work, and it does does the right thing automatically and enforces strong encryption by default (unlike a lot of personal security software). It interoperates seamlessly with people who don't use Signal but you have the option to invite them to install it with a single tap. Its protocol is an open standard that multiple companies have implemented, so theoretically anyone can write their own implementation of the client (Android, iOS) or server, or compile it for themselves. It's an SMS/MMS application, so you can use it as your default text messaging client on your mobile, plus it can do text message conferencing with multiple people automatically (it's a great way to keep in touch with friends if you're at the same con). There's even a desktop Signal client that runs inside of Google Chrome or Chromium (source code for the interested and curious).
So, why, exactly am I posting about Signal?
There is a little-known command-line implementation of Signal that I've been experimenting with because I eventually plan on writing a bot for my exocortex. In playing around with it, I've come to realize that it's not particularly friendly to use at all, and I might have to break down and use the dbus interface to do anything useful with it. Which I don't look forward to, but that's not the point. The point is, I've compiled some notes about how to use the command line version of Signal and I wanted to put them online in case somebody will find them helpful.