Commands
tldr man pages: https://tldr.sh
List of POSIX commands: https://en.wikipedia.org/wiki/List_of_POSIX_commands
The Art of Command Line: https://github.com/jlevy/the-art-of-command-line
Shell One-liners: https://github.com/trimstray/the-book-of-secret-knowledge#shell-one-liners-toc
Oh-heck, a terminal command for when you forget other terminal commands - https://news.ycombinator.com/item?id=30720834 - https://oh-heck.dev
Advanced macOS Command-Line Tools: https://saurabhs.org/advanced-macos-commands
Notes
zsh is the default shell in macOS since Catalina (10.15, released October 2019) - see https://support.apple.com/kb/HT208050
Command history is saved in ~/.zsh_history
.
Terminal shortcuts
- Ctrl + R: Recall
- Ctrl + R again to see next match
- Return to execute
- Ctrl + G to exit without executing
- Esc to exit but leaving searched command
- Ctrl + Z: send to the background
Various commands & tips
# set environment variable
NODE_ENV=production
# unset environment variable
unset NODE_ENV
- !!: run the previous command
- What shell is used:
echo $SHELL
- List all environment variables:
printenv
. You can also print a specific envar:printenv ANDROID_HOME
. (In Linux you can print many, egprintenv ANDROID_HOME PATH
, but does not work in macOS.)
Command-line pro tips: https://twitter.com/addyosmani/status/1264854298799665152
Use curly braces in the command-line to quickly create multiple related files with less typing source:
touch index.{js,css} # creates index.js and index.css
touch {P,H1,H2}.tsx # creates P.tsx, H1.tsx and H2.tsx
You can also use this with npm: https://twitter.com/nucliweb/status/1096327937308135425
Command substitution
https://www.gnu.org/software/bash/manual/html_node/Command-Substitution.html
AWS_ACCOUNT_ID=$(aws sts get-caller-identity --query Account --output text)
Aliases
On your .zshrc
or .bash_profile
put:
alias l='ls -la'
cd
cd # Go to user's home (~). You can also do 'cd ~'
cd - # Go to the previous directory
cd / # Go to the root directory
cd ~username # Go to the user's root directory
cp
cp -r dir1 dir2 # Recursively
mv
mv file.txt dir
rm
rm -r dir # Recursive is required to delete a directory
rm -r * # Remove all files in current directory, except hidden files
rm -r * .* # Remove all files in current directory, including hidden files
mkdir / rmdir
mkdir -p dir1/dir2/dir3 # With -p if dir1 and dir2 don't exist, it creates them
rmdir -p dir1/dir2/dir3 # With -p it removes dir1 and dir2 too
touch
Either updates the access or modification date of a file, or creates an empty file if it doesn't exist.
Useful to create locks, eg to avoid multiple editing or access. See https://unix.stackexchange.com/questions/109003/what-are-the-legitimate-uses-of-the-touch-command
echo
echo "Java home is $JAVA_HOME"
echo "something" >> file.txt # Appends
echo "something" > file.txt # OVERWRITES ALL FILE CONTENT
echo -n "abc" # Do not add a newline (at the end)
cat
Backup some file before modifying it, just in case:
cat file.txt > file-backup.txt # Equivalent to 'cp file.txt file-backup.txt'
less
If the file is big is better use less
not cat
.
less file.txt
Use /Whatever
for searching.
find
find . -type d -name "build"
find . -type d -name "build" -exec rm -rf {} +
find . -type f -name "*.iml"
find . -type f -name "*.iml" -exec rm -rf {} +
Exclude: find . -type d -name "dist" | grep -v 'node_modules'
See user-friendly alternative fd
- https://github.com/sharkdp/fd
diff
diff -qr Dir1 Dir2
# Exclude directories
diff -qr Dir1 Dir2 --exclude=.git --exclude=node_modules
tree
tree somefolder
To ignore something (eg a folder) use -I <wild-card-pattern>
. Eg tree -I node_modules
or tree -I venv
. There can be multiple -I options.
fc
fc [-e ename] [-lnr] [first] [last]
fc -s [pat=rep] [command]
https://www.geeksforgeeks.org/fc-command-linux-examples
List recent commands in history: fc -l
lsof
If we are running a server at (eg) port 3000 we can do lsof -i :3000
and it will print information about the process that started the server. Doing lsof -t -i :5000
gives the process id. Hence, to kill the process you can do kill -9 $(lsof -t -i :3000)
.
sed
On macOS, don't bother to try to use the built-in sed
, since you get the error 'sed: 1: "eas.json": invalid command code e' all the time. Use GNU sed instead, as advised here. Install it with brew install gnu-sed
. Then use gsed
instead of sed
, or alias it with alias sed='gsed'
, or add it to the path with PATH="/opt/homebrew/opt/gnu-sed/libexec/gnubin:$PATH"
.
https://www.gnu.org/software/sed
Manual: https://www.gnu.org/software/sed/manual/sed.html
Replace value in file:
sed -i "s/THE_VALUE/some_value/" file.txt
sed -i "s/THE_VALUE/$SOME_VAR/" file.txt
s
means substitute. See The s
Command for more options.
Another example. If we have:
const a = {
version: '0.0.1',
}
We can do:
sed -i "s|version: '.*'|version: '$VERSION'|" file.ts
sed: -e expression #1, char 19: unknown option to `s'
Beware that if the interpolated value contains a /
(eg a URL or a path) it will fail with:
sed: -e expression #1, char 19: unknown option to `s'
See:
- https://stackoverflow.com/questions/9366816/sed-fails-with-unknown-option-to-s-error
- https://stackoverflow.com/questions/24705650/sed-unknown-option-to-s-in-bash-script
Since you can use any delimiter, to fix it do for example:
sed -i "s|THE_VALUE|$SOME_VAR|" file.txt