Reset Terminal

Reset-Alacritty.md

Introduction

To reset your terminal, you can call reset from your shell, which is generally included with the target operating systems.

If you want to reset when you are not at a shell prompt (i.e., inside some other application), we can send an escape sequence in another way.

As an example, we can send a special escape sequence to the Nth tty:

echo -e "\ec" > /dev/pts/$N

Since Alacritty supports keybindings to execute arbitrary scripts, it is possible to map this reset action to some key combination.

This can be 1️⃣ wrapped into a script, which 2️⃣ Alacritty can be configured to execute.

1️⃣ Create script

You can use the script below to send the desired escape code.

ℹ️ First, the script extracts the PID of Alacritty from a known environment variable, ALACRITTY_LOG.

ℹ️ ALACRITTY_LOG has the form /tmp/Alacritty-1234.log, where 1234 corresponds to the process ID of Alacritty.

Copy the script to some well known location, for example bin in your home directory.

#!/bin/sh
if [ -z "${ALACRITTY_LOG}" ]; then exit 1; fi

TERM_PID="${ALACRITTY_LOG//[^0-9]/}"
tty=$(ps o tty= --ppid $TERM_PID)

echo -e "\ec" > /dev/$tty

2️⃣ Configure alacritty

In your alacritty.yml config, add a keybind to the script. For example, to bind CTRL+K to the reset action, add the following to the key_bindings section:

- { key: K,  mods: Ctrl,  command: path/to/reset-alacritty }

🎉 And you're all set. The rest of this doc just contains some info for the curious.

The config can be just the name of the script if your PATH is set load your expected binaries correctly.

- { key: K,  mods: Ctrl,  command: reset-alacritty }

A general solution

If you are on Linux and using X11, this alternative script using xdotool should be compatible with any given terminal emulator.

#!/bin/sh

focus_pid=$(xdotool getactivewindow getwindowpid)

tty=$(ps o tty= --ppid $focus_pid)

echo -e "\ec" > /dev/$tty

References

1. alacritty/alacritty#4152 (comment)
2. alacritty/alacritty#4199 (comment)

Discussions

1. alacritty/alacritty#4494
2. alacritty/alacritty#3997

Version History

• 0.1: Initial document made for the Alacritty wiki
  • Destroyed (i.e., rejected) from there

Addendum: in fact, Alacritty supports this feature 👍 (it responds correctly to the escape code, which results in all of scrollback being destroyed, in addition to any data on the screen).

The CTRL+K you may be used to from iTerm2, gnome-terminal and other emulators now works in Alacritty 👌 if you use the workaround described.

Ideally, configuration should be as simple as configuring the escape code directly in the yml file.

But for some reason (likely an implementation difference), Alacritty does not respond to the clearing code correctly (via its own/standard config).

Best workaround ever... don't know why this is alacritty does not add has it by default. It took longer to debate the "why not" than to code a solution :P

Thanks for this @avindra.

I changed the xdotool to a more sway friendly approach in my setup:

❯ bat ~/.local/bin/reset-active-tty
───────┬─────────────────────────────────────────────────────────────────────────────────────────────────────
       │ File: /home/jattali/.local/bin/reset-active-tty
───────┼─────────────────────────────────────────────────────────────────────────────────────────────────────
   1   │ #!/bin/sh
   2   │
   3   │ focus_pid=$(swaymsg -t get_tree | jq '.. | select(.type?) | select(.focused==true).pid')
   4   │
   5   │ tty=$(ps o tty= --ppid $focus_pid)
   6   │
   7   │ echo -e "\ec" > /dev/$tty
───────┴─────────────────────────────────────────────────────────────────────────────────────────────────────

And my alacritty config:

❯ bat ~/.config/alacritty/alacritty.yml | rg reset-active-tty
  - { key: K,          mods: Control, command: { program: "sh", args: ["-c", "~/.local/bin/reset-active-tty"] } }

This script almost works for me, thanks! The only problem I have right now is that when I execute this script with key binding or from another terminal, my target terminal is completely cleared, cursor is on first line in first column and prompt is not shown. In this case I need to hit Enter to get prompt or resize window or hit Ctrl-L. However if I run this command in target terminal as usual command then prompt is shown. Does anyone know how to make prompt appear?

Alacritty looks like this:

See also: alacritty/alacritty#3997

this is really amazing! I was looking for this! The only thing I am missing is that if I am not in a tail -f mode the prompt does not come back and I need to hit enter to do it. Is there a way to do that by echoing something to the device? I tried but could not really figure it out.

Thanks!

Hitting Enter after blanking the screen is necessary. There's probably a way to do that automatically but I'm not aware of the method.

If you want to avoid hitting enter, do the following. Setup everything according to this gist, but add a key binding action to the same key that sends a byte sequence to the running application using chars. According to the docs:

If the same trigger is assigned to multiple actions, all of them are executed in the order they were defined in.

So:

- { key: K,  mods: Ctrl,  command: path/to/reset-alacritty } 
- { key: K,  mods: Ctrl,  chars: "\x0d" } 

This will send/press enter right after the reset-alacritty command.

@insilications This works for me! ⚡ Thanks, you are a genius! 👍

it depends on what you are looking for, but this shortcut is good enough for me:

  - { key: K, mods: Ctrl, action: SpawnNewInstance }
  - { key: K, mods: Ctrl, action: Quit }

This rocks. I was about to leave alacritty because of that, plus the main guys attitude regarding this MUST HAVE feature for everybody who has to work with logging applications.
Massive thanks. Whew... I was about to send ctrl-z before and fg+enter after the built in clearing sequence and I hated myself to have invested too much into wrong terminal ;-) Now I'm sort of fine again with it.