Cheat Sheets

Bash

Created: 2017 October 11th

Updated: 2021 January 10th

Human Readable $PATH output

Use this to nicely format the $PATH variable:

GNU Bash icon
echo -e ${PATH//:/\\n}

Change default shell

Use chsh utility to change your default shell:

GNU Bash icon
# list out the shells available with -l
chsh -l
# if that doesn't work try
cat /etc/shells
# /bin/bash
# /bin/zsh
# /bin/fish
# set the default shell (with -s) to fish
chsh -s /bin/fish
# set the default shell (with -s) to zsh
chsh -s /bin/zsh

Kill process on port

List any process running on port 8000

GNU Bash icon
lsof -i:8000

Output will look similar to this.

COMMAND PID USER
chrome 16085 iamuser

Then kill it with kill.

GNU Bash icon
kill -9 16085

Add an alias

GNU Bash icon
# open your bash_profile with nano
nano ~/.bash_profile
# add your alias
alias f='fish'
# ctrl+x then y to save

Sort alphabetically

You may find that commands like ll are under your ~/.bashrc file, if not then add the following as an alias:

GNU Bash icon
ls -lart | sort -k9,9

See file permissions

If you need to set the permission on a file (with chmod) but don’t know what the permissions of similar files are like you can use stat, the following command displays the permissions of the contents of the .ssh/ folder:

GNU Bash icon
stat -c "%a %n" ~/.ssh/*

Open the SSH agent each time you open a new terminal.

Tired of having to enter your SSH password each time you want to do a git operation?

Add the following to your ~/.bashrc file.

GNU Bash icon
# nano ~/.bashrc
[ -z "$SSH_AUTH_SOCK" ] && eval "\$(ssh-agent -s)"

Search Bash history

Want to search for an entry in your Bash history?

Use Ctrl+r then enter your search term.

Remove command from bash history

Accidentally added your password as a bash command?

To remove that from the bash history:

GNU Bash icon
# list out history with
history

Then take the number from the output:

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471 ssh-agent
472 exit
473 kill 53111
474 super secret password
475 history

Then delete the line you want removed:

GNU Bash icon
history -d 474

Check your history again and gone until you do it again.

Move the contents of a folder to another folder

This will move everything in the Downloads folder to the Videos folder including any folders inside Downloads.

GNU Bash icon
mv ~/Downloads/* ~/Videos