Have Zsh Tell You If A Command Is Real

Shell Programming

Hello there! As a technical enthusiast and someone who is always looking to optimize my workflow, I’ve come across a fantastic feature in zsh that has truly made a difference in my day-to-day command line usage. Today, I want to share with you the power of having zsh tell you if a command is real. This may sound like a small detail, but trust me, once you start using it, you won’t look back.

Understanding the Feature

For those who may not be familiar, zsh is a powerful shell that offers a wide range of features and customization options for command line users. One particularly handy feature is the ability to have zsh check if a command is an actual executable file on your system. This may seem like a basic check, but it can be incredibly useful, especially when working in complex environments with numerous installed applications and tools.

When you type a command into zsh, it can immediately let you know whether the command exists as an executable file. It does this by performing a lookup in the directories listed in your $PATH environment variable. If the command is found, zsh will execute it as normal. If not, zsh will provide a helpful error message, indicating that the command is not found.

Enabling the Feature

To enable this feature, you can simply add the following line to your .zshrc file:

autoload -Uz command-not-found
command_not_found_handler() { echo "Command not found: $1" }

Once this feature is enabled, zsh will automatically check for the existence of commands as you type them, providing instant feedback on the validity of your inputs.

Personal Experience

I can’t emphasize enough how much of a time saver this feature has been for me. As someone who often experiments with different command line tools and utilities, it’s easy to mistype a command or forget whether a certain tool is installed. With zsh’s ability to verify commands, I no longer have to second-guess myself. It’s like having an extra set of eyes watching out for potential mistakes.

What’s even more impressive is that this feature encourages me to explore and discover new commands with confidence. I can quickly determine whether a command is available on my system without having to resort to trial and error. This has not only improved my efficiency but has also expanded my command line repertoire.


In conclusion, having zsh tell you if a command is real is a simple yet impactful feature that has greatly enhanced my command line experience. By providing real-time feedback on the validity of commands, it has empowered me to navigate my system with greater ease and confidence. If you’re a fellow command line enthusiast, I highly recommend giving this feature a try and seeing the difference it can make in your daily workflow.