Reload Zsh Configuration

I’ve been using Zsh on-and-off for a very long time (15+ years), but I still occasionally learn something new about it.¹ Yesterday I was setting up oh-my-zsh on a new computer and I’ve noticed they had added a command for reloading the Zsh configuration:

$ omz reload

I assumed this was just an alias for . .zshrc (a.k.a. source .zshrc), which I had been doing for ages, but it turns out it’s actually an alias for:

$ exec zsh

Instead of reloading a particular configuration file this reloads your Zsh process completely. Why would you want to do this instead of using source/.? The main advantage of exec zsh is that no rogue state is left after such a reload - e.g. env variables you’ve previously set that are no longer in your config. By the way, exec (like source) is just a Zsh built-in. Here is what the documentation has to say about it:

Replace the current shell with command rather than forking. If command is a shell builtin command or a shell function, the shell executes it, and exits when the command is complete.

Going forward I’ll definitely be using this approach, as I love to start my shell with a clean slate (state?). Keep hacking!

1. Not to mention I constantly re-learn a lot of things I knew and forgot. ↩