Published January 28, 2019
Typos happen. Fix them with these two tricks.
Hi everyone, Brian here to talk about how to quickly fix mistakes when you typed out a command.
It happens, You make a typo and don’t realize it until after you typed the command.
One of the most common places this happens is when you’re trying to do something with
sudo and you forgot to use
$ mkdir /var/test_dir
That command fails.
mkdir: cannot create directory ‘/var/test_dir’: Permission denied
If you type two exclamation points,
!!, it’ll run your previous command again.
$ !! mkdir /var/test_dir mkdir: cannot create directory ‘/var/test_dir’: Permission denied
But if you type
$ sudo !! sudo mkdir /var/test_dir
it runs your previous command again with
sudo. Not ashamed to admit I use this one all the time.
Sometimes you might just be typing too fast and you’ll make a typo in the command:
$ mdkir test_dir mdkir: command not found
The command is supposed to be
mkdir. I can fix that with a little bit of substitution:
$ ^mdk^mkd mkdir test_dir
Hurray! It’s fixed! The new command prints and executes.
There you go! A couple of quick ways to fix mistakes when typing.
These approaches leverage a feature called history expansion, which you can learn more about in the book.
Thanks for watching!