Erik L. Arneson — Writer and Software Developer

An Emacs Application Launcher for Regolith

2025-11-19T00:00:00+00:00

I run the Regolith Desktop Environment on my laptop, which I love because it provides a convenient GNOME wrapper and interface for the i3 tiling window manager. Regolith relies on a program called ilia for application launching, and sometimes ilia gets caught in some kind of CPU-churning state that locks up my whole system. I have not been able to figure out what is causing it, so I (of course) turned to Emacs for a solution.

Turning to `consult-omni`

Armin Darvish has created a powerful Emacs package called consult-omni, which provides a wrapper around consult for searching through any number of information sources. I believe consult-omni was originally intended to query web search engines and document databases, but Darvish has also provided a search mode for your local desktop applications, and can act as an application launcher.

Darvish provides an example application launcher in his consult-omni YouTube tutorial. The source code is straightforward, but I wanted to tweak it just a little. You can view his original on the project’s wiki on GitHub. You can watch him explain his technique below.

After a few tweaks, here is what I came up with.

(defun consult-launcher ()
  "A launcher suitable for use from a window manager."
  (interactive)
  (let* ((width (floor (* 0.6 (display-pixel-width))))
         (height (floor (* 0.6 (display-pixel-height))))
         (left (floor (* 0.2 (display-pixel-width))))
         (top (floor (* 0.2 (display-pixel-height))))
         (params `((name . "omni-launcher")
                   (width . ,(cons 'text-pixels width))
                   (height . ,(cons 'text-pixels height))
                   (left . ,left)
                   (top . ,top)
                   (minibuffer . only)))
         (frame (make-frame params)))
    (with-selected-frame frame
      (select-frame-set-input-focus frame)
      ;; If i3 is running and there is a control socket, let's tell
      ;; it we are a floating frame.
      (if (getenv "I3SOCK")
          (call-process "i3-msg" nil nil nil
                        (format "[id=%s] floating enable"
                                (s-trim (shell-command-to-string "xdotool getactivewindow")))))
      (unwind-protect
          (progn (consult-omni-apps-static ".*" (propertize "> " 'face 'consult-omni-path-face))
                 nil)
        (progn
          (when (frame-live-p frame) (delete-frame frame))
          nil)))))

I made two changes to get this to work nicely with i3. First, I removed the yequake dependency. Second, I added a call to i3-msg that sets the launcher frame as floating, which makes it much nicer to use. Like Darvish’s version, you can run this from the command line:

emacsclient -e '(consult-launcher)'

Adding an `ilia` fallback

Don’t tell all the other Emacs users, but I don’t have Emacs set up to launch automatically when I start my computer and log into X11. I probably should, huh? Also, there are times when I (gasp!) shut down Emacs, usually to restart it or fix something that I have broken. When those times happen, I want to be able to launch applications, so I need a failsafe in case consult-launcher isn’t available!

To solve this, I created a simple shell wrapper script, which looks like this:

#!/bin/bash

# Check if Emacs server is running by looking for the server socket
# Default server name is "server", but you can change this if needed
SERVER_NAME="${EMACS_SERVER_NAME:-server}"
SERVER_FILE="${XDG_RUNTIME_DIR:-/tmp}/emacs/${SERVER_NAME}"

if [ -S "$SERVER_FILE" ]; then
    # Emacs is running, use emacsclient to launch your application
    emacsclient -e '(consult-launcher)'
else
    # Emacs is not running, fall back to ilia
    ilia -p apps
fi

If you want to use this, the important part is that SERVER_FILE points to the socket that your Emacs server uses. Make sure that emacsclient and ilia are both in a reasonable location so your shell can find them, then bind this command to whatever you usually use to launch ilia.

By the way, if you are using Regolith’s normal method of launching ilia, you can add your shell script to your Regolith configuration pretty easily. Open $HOME/.config/regolith3/Xresources in your text editor, and add the line:

wm.program.launcher.app: /path/to/your/launcher.sh

You can then run xrdb -override $HOME/.config/regolith3/Xresources and it should work! Good luck.

Drawbacks

One of the nice things about ilia is that it keeps track of applications your run frequently, so they tend to bubble up to the top of its application listing. The Emacs method doesn’t do that. I don’t mind so much, I always end up typing in application names. It is fun to use Emacs as an application launcher, and I hope that it helps me avoid the CPU-churn problem that ilia has been experiencing far too often.

Have I come up with a clever solution, or a lazy workaround? I’m looking forward to hearing your thoughts.

Some Great Fish Shell Plugins

2022-09-23T17:44:00+00:00

As a long-time Linux user, I am pretty comfortable with command line interfaces. However, as I started learning more about automation and how important it is to get your computer to do more work for you, I leaned toward wanting my command line shell to do more. Eventually I switched to fish shell, a very user-friendly shell with excellent scripting capabilities that is far more readable and less obscure than bash.

Plugins for fish

There have been a few plugin managers over the years, but the one that seems to be the best maintained and most usable is fisher, created by Jorge Bucaran. It allows you to easily install plugins straight from GitHub repositories, while updates can be executed with a simple fisher update on the command line.

z

One of the greatest command-line time savers ever is the z command. Originally a bash script, it has been ported to fish and, frankly, I love it.

What does it do? z provides shorthand for visiting directories based on a combination of frequency and recency—or "frecency".

If you frequently visit the /opt/calibre directory, a z calib command will allow you to jump straight there.

If you already have fisher installed, just use fisher install jethrokuan/z and start playing around with z.

You can read more about z here.

pisces

Your IDE has been handling your parenthesis for ages. Now your shell can do the same! The pisces plugin has automatic matching symbol management for parenthesis, braces, quotes, and others.

Install it with fisher using the command fisher install laughedelic/pisces and be matching parens in seconds!

plugin-emacs

Automation can help you interact with your editor from your shell. The Emacs plugin for fish was originally written for an unmaintained plugin manager called Oh My Fish. However, I wanted the plugin to work with fisher, so I made my own fork.

How does it work? This plugin adds easy commands like ef and ed that allow you to open files and directories in Emacs quickly.

Install it quickly using the command fisher install pymander/plugin-emacs and read more about it here.

vfish

Emacs users have probably heard of vterm, which is the Emacs package that interacts with libvterm. It is a powerful terminal emulator that runs in an Emacs buffer. I wrote a fish plugin called vfish that simplifies using fish in vterm.

How does it work? Inside a vterm session, this plugin adds fish commands like vf and vd to open files and directories quickly. It mirrors the Emacs plugin.

Install it using the command fisher install pymander/vfish and read more about it here. Note that it will require some code to be added to your Emacs startup file.

apt

For Debian and Ubuntu users, the Oh My Fish apt plugin works seamlessly with fisher.

What does it do? The apt plugin adds a wrapper around the apt and apt-get commands that simplify package management from the command line.

Install this plugin quickly with fisher install oh-my-fish/plugin-apt and then read more about it.

What's your favorite fisher plugin?

I love finding plugins that can help me automate more of my everyday tasks and workflows. What's your favorite fisher plugin?

Leave a comment below and let me know! Be sure to include a link.

Handy Tools for the Bourne Again Shell

2014-12-01T16:38:30+00:00

If you’re a Unix geek, you’ve probably used bash, the Bourne-Again Shell. If you’ve been around a while, you’ve probably spent a lot of time customizing bash.

Back when I worked for Yahoo!, my friend Bryan gave me a great directory stack for bash. I loved it, so I rewrote it and have been hacking on it and using it ever since. Observe.

[user@host:~]$ cd /tmp
[user@host:/tmp]$ cd /var/log
[user@host:/var/log]$ dl
1   ~
2   /tmp
3 * /var/log
[user@host:/var/log]$ go 1
1   /home/user
[user@host:~]$ go log
3   /var/log
[user@host:/var/log]$ 

In addition to the handy new go command, it also includes b and f for moving backwards and forwards on the stack. It was inspired by pushd and popd, but it’s so much more.

If you’d like to check it out, take a look at my bashtools repository on GitHub or just download version 1.0. I don’t change it very often, but I’m thinking of hammering out a long-standing bug in the directory stack code.

N.B. If you use all of my scripts, you’ll get some great prompts for your xterms. You’re welcome!