[TIPS] Fast Launching by using singleton Kitty

[lumynou5]

I want to share how I launch Kitty faster on my laptop. Hope this helps you too.

TL;DR Set a hotkey (if you like) to run the following command:

sh -c 'ps -C kitty >/dev/null || kitty -1 --detach --start-as hidden -o allow_remote_control=socket-only --listen-on unix:@kitty; kitten @ --to unix:@kitty focus-window -m "not id:1 and state:focused" 2>/dev/null || kitty -1'

---

It's a bit long so I split it into few lines to explain the intent here. Though it's mostly useless if you read the documentation.

ps -C kitty >/dev/null ||
  kitty -1 --detach --start-as hidden -o allow_remote_control=socket-only --listen-on unix:@kitty
kitten @ --to unix:@kitty focus-window -m "not id:1 and state:focused" 2>/dev/null ||
  kitty -1

I also removed the sh wrapper that is used only because hotkey accepts a single command.

The first line is quite simple. It checks whether there is a Kitty process running, and if there isn't, the second line is evaluated to start Kitty.

It runs Kitty like a deamon to let you always reuse the Kitty singleton rather than create a new process. -1 for single instance, --detach to make it detach from the sh wrapper so the latter can exit after these commands, --start-as hidden to hide the OS window, and -o allow_remote_control=socket-only --listen-on unix:@kitty for remote control (will explain latter). You probably also want --session none if you have startup session set in your configuration.

If your sleep implementation supports sleep infinity, you may put it at the end of the kitty command, so the "background window" will sleep instead of starting a shell. This could reduce the wasted memory usage, especially shells could have memory leak. A random large number also works if infinity isn't supported, since your computer probably won't be up for 292 billion years.

And the third line tries to focus the last used window because I don't want to have multiple OS windows opened; you can remove this line if you don't like that, or maybe do other things. It needs remote control to allow kitten @ to control the Kitty process, so I set Unix socket above; you can also set these in your config file instead of overwritting by CLI. The state:focused is true for the last focused window even after you no longer focus on Kitty, so you'll be able to go back where you were, and the not id:1 excludes the first window in the hidden OS window.

Then, the fourth line launches an OS window of Kitty if there isn't one (kitten @ fails if such window doesn't exist).