For practicing English
list
ls my_folder # Simple
ls -la my_folder # -l: show in list format. -a: show all files, including hidden. -la combines those options.
ls -alrth my_folder # -r: reverse output. -t: sort by time (modified). -h: output human-readable sizes.
tree # on Linux
find . -print | sed -e 's;[^/]*/;|____;g;s;____|; |;g' # on MacOS
# Note: install homebrew (https://brew.sh) to be able to use (some) Linux utilities such as tree.
# brew install tree
create
touch 'new file' # updates the file's access and modification timestamp if it already exists
# or
> 'new file' # note: erases the content if it already exists
mkdir 'untitled folder'
# or
mkdir -p 'path/may/not/exist/untitled folder'
remove
# remove permanently
rm my_useless_file
rm -r my_useless_folder
find . -name "*.bak" -type f -delete
copy
cp readme.txt documents/
cp -a myMusic myMedia/
# or
cp -a myMusic/ myMedia/myMusic/
duplicate
cp readme.txt readme.bak.txt
More advanced:
cp readme{,.bak}.txt
# Note: learn how the {} works with touch foo{1,2,3}.txt and see what happens.
cp -a myMusic/ myMedia/
# or if `myMedia` folder doesn't exist
cp -a myMusic myMedia/
move
# Always use a trailing slash when moving files
mv readme.txt documents/
mv myMedia myMusic/
# or
mv myMedia/ myMusic/myMedia
rename
mv readme.txt README.md
mv myMedia/ myMusic/
merge directories
rsync -a /images/ /images2/ # note: may over-write files with the same name, so be careful!
view
cat apps/settings.py
# if the file is too big to fit on one page, you can use a 'pager' (less) which shows you one page at a time.
less apps/settings.py
imgcat image.png
# Note: requires iTerm2 terminal.
search
grep -i "Query" file.txt
# search all files in current working directory, quickly (entire disk in less than 15 minutes)
ripgrep -i "Query"
# brew install ripgrep
show info
du -sh node_modules/
df -h # show disk size
stat -x readme.md # on macOS
stat readme.md # on Linux
# check cpu usage
top
htop
# know whether your computer is under load
glances
# brew install glances
open
xdg-open file # on Linux
open file # on MacOS
start file # on Windows
open -a appName file
zip
zip -r archive_name.zip folder_to_compress
unzip archive_name.zip
unar archive_name.zip
unar archive_name.7z
unar archive_name.rar
unar archive_name.ISO
unar archive_name.tar.gz
peek
zipinfo archive_name.zip
# or
unzip -l archive_name.zip
lsar -l archive_name.zip
lsar -l archive_name.7z
lsar -l archive_name.ISO
lsar -l archive_name.rar
lsar -l archive_name.tar.gz
find
find my_folder -mtime +5 # find all files modified more than 5 days ago
calendar
cal
cal 11 2018
date
date +%m/%d/%Y
date -d "+7 days" # on Linux
date -j -v+7d # on MacOS
calculator
bc -l
force quit
killall -9 program_name
poweroff or reboot
# poweroff
sudo shutdown -h now
# reboot
sudo shutdown -r now
USB
df # locate USB drives
sudo umount /dev/sdb1 # unmount USB drives
# format USB drives
# FAT32
sudo mkfs.vfat /dev/sdb1
# NTFS
sudo mkfs.ntfs /dev/sdb1
# exFAT
sudo mkfs.exfat /dev/sdb1
sudo fsck /dev/sdb1 # check USB format
run command on all files of a directory
for FILE in *; do echo $FILE; done
check
# check server response
curl -i umair.surge.sh
# curl's -i (--include) option includes HTTP response headers in its output.
# check network connectivity to a remote address and port
nc -vz www.google.com 443
nc -vz 1.1.1.1 53
# check DNS config of a domain
dig www.google.com
# check the ownership and registration of a domain
whois www.google.com
Hotkeys
Ctrl + A Go to the beginning of the line you are currently typing on
Ctrl + E Go to the end of the line you are currently typing on
Ctrl + L Clears the Screen, similar to the clear command
Ctrl + U Clears the line before the cursor position. If you are at the end of the line, clears the entire line.
Ctrl + H Same as backspace
Ctrl + R Lets you search through previously used commands
Ctrl + C Kill whatever you are running
Ctrl + D Exit the current shell
Ctrl + Z Puts whatever you are running into a suspended background process. fg restores it.
Ctrl + W Delete the word before the cursor
Ctrl + K Clear the line after the cursor
Ctrl + T Swap the last two characters before the cursor
Ctrl + F Move cursor forward one character
Ctrl + B Move cursor backward one character
Esc + T Swap the last two words before the cursor
Alt + T Same as Esc + T
Alt + F Move cursor forward one word on the current line
Alt + B Move cursor backward one word on the current line
Esc + F Same as Alt + F
Esc + B Same as Alt + B
Alt + . Paste the last word of the most recently command
Tab Auto-complete files and directory names
