systemE

A lightweight systemd replacement written in Emacs lisp

About

Using the tooling in this repo, I am able to boot from linux to sinit as PID1, and from there to Emacs acting as PID2 using --script mode, performing all typical rc.boot system initialization using Emacs lisp until we hit the getty.

Additionally from the getty, I use Emacs as a login shell, dotfiles manager, package-manager front-end, startx / xinitrc replacement, and Window Manager. I have nearly purged shell scrips from my life entirely. For more information about these things, see my .emacs repo.

Status

• The boot.el and shutdown.el scripts are finished and I use them on my local machine. No support for fancy stuff like luks is planned.

• We still depend on suckless.org's sinit for PID1 and this needs to be rewritten in in elisp.

• We still depend on busybox runit for a process supervisor and this needs to be reimplemented in elisp, or atleast converted to gnu shepherd. This is my number one goal. An Elisp service supervisor that could be communicated to using emacsclient as root would be really fun.

• One pain point is getting a statically compiled Emacs. We don't require this, but it sure would be nice. Unfortunately, when I statically compile Emacs using musl, it results in a broken Emacs.

• Emacs is PID 2. While it is easy to execute Emacs as PID 1, Emacs does not reap zombies and I do not know how to make it reap them yet. I have found Emacs listens for the URS1 and URS2 signals, but not SIGCHLD which is what we need. We also need to figure out how to call wait () after that. Also I really like sinit at this point, not in a big hurry to swap it out.

This repo is technically a kiss linux package

I don't recommend you install this as a package if you use Kiss Linux though. Instead I would recommend you poke around at it and see if you find anything that is useful for yourself that way.

I took some shortcuts in packaging it and it is not an exemplary example of a kiss package. It's very hacky. However, it does display the flexibility and simplicity which makes the kiss package manager fun to work with.

So this repo compiles and installs all of my project dependencies "batteries included" to /boot ...

This includes:

• emacs-nox
• elisp files
• sinit
• ubase
• sbase
• dash

The ever-growing list of Helpful / Credits / Thank You's

;; https://github.com/kisslinux/init/blob/master/lib/init/rc.boot
;; https://github.com/kisslinux/init/blob/master/lib/init/rc.shutdown
;; https://gist.github.com/lunaryorn/91a7734a8c1d93a8d1b0d3f85fe18b1e
;; https://busybox.net/FAQ.html#job_control
;; https://stackoverflow.com/questions/23299314/finding-the-exit-code-of-a-shell-command-in-elisp
;; https://github.com/Sweets/hummingbird
;; https://felipec.wordpress.com/2013/11/04/init
;; https://www.emacswiki.org/emacs/PersistentProcesses
;; https://stackoverflow.com/questions/17479529/self-contained-portable-emacs