Shell text substitution

07 Apr, 2024 • 111 words • 1 min • updated 05 Sep, 2025

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I learned a neat shell trick this week. In both bash and zsh you can use the circumflex / caret (^) symbol to find & replace a word from the previous command.

Usage: ^prev^next. It’s best illustrated with examples:

terraform #

Instead of running:

     shell
     
   
terraform init -var-file /path/to/foo.tfvars
terraform plan -var-file /path/to/foo.tfvars
terraform apply -var-file /path/to/foo.tfvars

Run:

     shell
     
   
terraform init -var-file /path/to/foo.tfvars
^init^plan
^plan^apply

systemd #

Instead of running:

shell

sudo systemctl restart nginx
sudo systemctl status nginx

Run:

shell

sudo systemctl restart nginx
^restart^status

one observation #

zsh will run the substitution right away, whereas bash will allow you to review and edit the replaced command before running it.