| - Pipes the result of a command into a subsequent command
> - Redirects the output of the result of a command
2> - Redirects the stderr as output of a command
* - Asterisk * or wildcard
~ - Home directory shortcut
$ - Any string which ends with a given string, e.g.: 'png$'
^ - Any string which starts with a given string, e.g.: '^$Screen'
Ctrl-a - Moves the cursor to the beginning of the line
Ctrl-e - Moves the cursor to the end of the line
Option-RightArrowKey - Moves the cursor forward by a word
Option-LeftArrorKey - Moves the cursor backward by a word
Ctrl-t - Swaps the current character with the one preceding it
Ctrl-l - Clears the screen
Ctrl-r - Reverse search
Ctrl-s - Reverses the search direction
Ctrl-g - Leave the search
Ctrl-k - Cut / kill to the end of the line
Ctrl-u - Cut / kill to the beginning of the line
Ctrl-y - Yanks the line
Ctrl-w - Cut / kill to the previous whitespace of the line
Alt-d - Cut / kill to the next whitespace of the line
Ctrl-x-e - Edits the current command in an editor
alt-. - Repeats the previous argument
sudo !! - !! expands into the previous command
sudo !N - !N expands into the nth previous command in the history list
ls !$ - !$ expands into the previous command's last parameter
ls index.* - Matches any file with an arbitrary file ending
ls index.??? - Match any file with a three letter file ending
cmd1 && cmd2 - Executes the first and then the second command
cmd1 || cmd2 - Executes cmd1 and then cmd2 if cmd1 returns a non-zero exit code
cmd1 | cmd2 - Executes both commands sequentially by sending cmd1 output to cmd2
cmd1 |& cmd2 - Execues both commands sequentially by sending cmd1 output and error data to cmd2
cmd1 ; cmd2 - Executes both commands sequentially regardless of the exit codes
cmd1 & cmd2 & - Executes both commands as background jobs
pushd /var/www/html - Changes directory and pushes the directory on the stack
dirs - Shows the current directories on the stack
popd - Changes directory and pops the directory from the stack
(cd /pathtosome/dirc; somecommand) - Executes somecommand in a subshell in a specific directory
history - Shows the historical commands entered in the shell
history 3 - Shows the previous three command of the history
history | sort -nr | less - Shows the latest to earliest entry in less
history | grep -w cd - Shows the historical commands containing the word cd
history | peco - Shows the historical commands with an interactive search
history | cut -c 8- - SHows the historical commands without line numbers
history -c - Clears the history
hh - Provides an interactive search of the historical commands
echo $HISTSIZE - Shows the history size
echo $HISTFILE - Shows the location of the shell history
HISTCONTROl=ignoredups - Sets the variable which ignores duplicates in the history
!! - Repeats the previous command even if it was only printed
!grep - Repeats the most previous command starting with grep
!?grep? - Repeats the most previous command containing grep
!-3 - Repeats the third previous command from the history
!-3:p - Prints the third previous command from the history
!!:s/jg/jpg/ - Repeats the previous command but replaces jg with jpg
$_ - Repeats the last argument of the previous command
!$ - Repeats the last argument of the previous command
!!:n - Repeats the n-th argument of the previous command
eval $command - Runs a command stored in a variable (breakout possible!)
which cp - Locates a command in the search path
type cp - Locates a command in the search path including aliases, functions and shell builtins
echo $PATH | tr : "\n" - Shows the directories of the search path
alias - Shows the available aliases
source .zshrc - Rereads a configuration file
cd dir && touch new.txt - Conditional list of commands where the second command is only executed if the first command was successful
cd dir || mkdir dir - Conditional list of commands where the second command is only executed if the first command was not successful
sleep 300; echo "remember to walk the dog" - Unconditional list where the second command is executed if the first command is done
mv $(grep -l "Artist: Kansas" *.txt) kansas - Command substitution
diff <(ls *.jpg | sort -n) <(seq 1 1000 | sed 's/$/.jpg/' - Process substitutuion where <( performs the commands in a new process
bash -c "ls -l" - Passes the given command to a new shell
echo "ls -l" | bash - Pipes the given command to a new shell
echo "ls -" > outfile" | ssh -T myhost.example.com - Passes a given command to a remote host using ssh
read -s -k '?Press any key to continue.' - Waits in zsh for any key
read -s -k $'?Press any key to continue.\n' - Waits in zsh for any key with new line
vared -p 'What would you like to do?: ' -c tmp - Input a line of text in zsh
ls > output - Redirects the stdout
cp nonexistent.txt file.txt 2> errors - Redirects the stderr
cp nonexistent.txt file.txt 2>> errors - Redirects the stderr and appends to erros
ls &> output - Redirects both stdout and stderr
echo 'filename with spaces.txt'
echo "filename with spaces.txt'
echo filename\ with\ spaces.txt
echo "with double quotes $VARIABLES are evaluted"
echo 'with single quotes $VARIABLES are not evaluated"
echo "with double quotes \$VARIABLES are not evaluated if the \$ is esacaped"
cat <<< 'hello' - Passses a here string to the cat command
cat <<EOF - Passes a here document to the cat command
bat < /home/foobar - Passes the foobar file to the bat command std in
find . -name "*.tmp" -print0 | xargs -0 rm - Passes the result of the first command to the second command using xargs
ls | xargs -I XYZ echo XYZ is my favorite food - Passes the result of ls to xargs where XYZ is a placeholder for the passed argument
mv file{,extension}.log - Appends "extension" to the file name
for f in *.pdf; do mv "$f" "$(date "+%Y%m%d"-"$f").pdf"; done - Prepends file date to the file name
for f in *; do mv $f "$(echo $f | sed s/20211100/20211109/g)"; done - Renames files using sed search and replace
for f in *.*; do mv -v "$f" "${f:11}"; done- Removes first eleven characters from a filename
Renames file ending of all files matching *.txt, where *.txt is a globbing pattern, -- marks the end of the option list, ${f%.txt} is a parameter expansion
for f in *.txt; do
mv -- "$f" "${f%.txt}.text"
done
tr --delete '\n' < file.txt - Removes newline character from file.txt
tr -d '\n' < file.txt > newfile.txt - Removes newline character from file.txt and writes the result to newfile.txt
echo bla | tr 'abcd' 'jkm' - Replaces all occurences of a character with another character
echo foobar | sed 's/bar/bla/' - Replaces the first occurence of bar with bla
echo foobar | sed 's/bar/bla/g' - Replaces all occurences of bar with bla
echo foobar | cut 2- | rev | cut 2- | rev - Removes the first and the last character of a string
ls -l /usr/lib | cut -c1 - Lists the /usr/lib directory and extracts the first column
cut -f1 grades | sort | uniq -c - Extracts the first column from grades, sorts and counts unique elements
cut -f3 file.txt | sort -nr | head -n1 - Extracts the third column, sorts reverse and shows the first element`
head -n5 /etc/passwd | cut -d: -f1 - Extracts the fifth column of /etc/passwd and extracts the first column using the : delimiter
md5sum *.jpg | cut -c1-32 | sort | uniq -c - Takes a subpart of the md5sum, sorts and counts duplicates
echo {1..10} - Prints numbers from 1 to 10
echo {10..1} - Prints the numbers from 10 to 1
ls file{2..4} - Lists the files file2 file3 and file4
ls file[2-4] - Matches existing filesnames as square brackets are pattern matching
touch count-{123}.txt - Generatres three files count-1.txt, count-2.txt and count-3.txt
touch count-{1..3}.txt - Generates the same files as above
ls -ld $(date +%B).txt - Performs a command substitution which embeds the result in an another command
echo ${animal}s - Performs a parameter substitution where a character immediately follows the variable name
mkdir dir && cd $_ - Creates a command while changing directory to it as $_ holds the argument passed to the previous command
echo !^ - Echos the first argument of the previous command
echo !$ - Echos the last argument of the previous command
echo !* - Echos all arguments of the previous command
echo !:2 - Echos the second argument of the previous command
echo !:2-3 - Echos the second to third argument of the previous command
echo !:2-$ - Echos the second to last argument of the previous command
echo !:2* - Echos the second to last argument of the previous command
echo !:0 - Echos the previous command
!! - Repeats the previous line
Performs a command substitution which considers a variable $var1.
var2=$(echo "$var1")
yes - Repeats print the character y until terminated
yes woof! - Repeats printing woof! until terminated
openssl rand -base64 12 - Generates a base64 string with a length of 12
openssl rand -hex 13 - Generates a hex string with a length of 1## Generating
less +f - Less and follow (shift-f to reattach after scrolling)
dosth & - Runs the command in the background, the process can be stopped using ctrl+z and continue it with bg or in the foreground with fg
nohup dosth & - Runs the command in the background while decoupeling it from unix signals
dosth &> /dev/null & - Runs the command in the background while detaching it from the output/error streams of the shell
jobs - Shows the currently running jobs
fg - Return to the background job
fg %2 - Return to the background job 2
kill %2 - Kill the background job 2
Ctrl-C - Kill the current foreground job
Ctrl-Z - Pause the current foreground job
bg - Background and resume a job again
echo "command_to_be_run" | at 09:00 - Runs the given command at 9 am
at 09:00 -f /home/linux/script.sh - Runs the given command at 9 am
cat somefile | tee -a log.txt | cat > /dev/null - Log output but not show on the console
export E="I am an environment variable - Sets an environment variable
L="I am just a local variable - Sets a local variable
for dir in */; do
zip -r ${dir}.zip $dir
done
Iterates through the directories in the current directory and zips the directories.
for COLOR in red white; do
< wine-$COLOR.csv tr '[A-Z]; ' '[a-z],_' | tr -d \" > wine-${COLOR}-clean.csv
done
Iterates the string list 'red white' and applies it to the line which follow do and prepends done. tr replaces and deletes some characters.
`for i in {0..100..2}
> do
> echo "$i^2" | bc
> done | trim
Iterates from 0 to 100 with steps of 2 and passes the value to bc.
$ while read line
> do
> echo "Sending invitation to ${line}."
> done < emails
Reads from the stdin an echos some text.
$ for chapter in /data/*
> do
> echo "Processing Chapter ${chapter}."
> done
Loops over files in a directory.
$ while read line; do
> echo "$line"
> done < "$filename"
Loops over the lines of a file.
$ seq 0 2 100 | parallel "echo {}^2 | bc" | trim - Iterates a sequence and passes the value to a parallel execution of bc
Loops over a range of dates using brace expansion.
for i in 2015-01-{01..31} ...
Loops over a range of dates using GNU date:
d=2015-01-01
while [ "$d" != 2015-02-20 ]; do
echo $d
d=$(date -I -d "$d + 1 day")
# mac option for d decl (the +1d is equivalent to + 1 day)
# d=$(date -j -v +1d -f "%Y-%m-%d" $d +%Y-%m-%d)
done
Loops over an array of directories:
array=(*/)
for x in array; do
echo $x
done
fc - Fix or change a really long command that you run last with a text editor
ls -s - Don't add a command to the history
ls $_ - Rerun a command (i.e. ls) with the last argument
ls !$ - Rerun a command (i.e. ls) with the last argument
tar -zcvf archive.tar.gz directory-name - Tar.gz a whole directory
curl -h "Accept-Encoding: gzip" -I https://www.google.com - Retrieves a web page asking for a gzip compression
rsync -avu --delete "/home/user/A/" "/home/user/B" - Syncs the files of A into B while preserving the file system attributes, verbosly, with a newer modification time and delete if a file does not exist in the source
wscat -c ws://websocket-echo.com - Connects to host via web sockets
date +"%Y%m%d-%H%M%S" - Return a formatted datetimestamp
date - Prints the date in the default format
date +%Y-%m-%d - Prints the date in the year-month-day format
date +%H:%M:%S - Prints the date in the hours:minute:second format
date +"I cannot believe it's already %A!" - Prints the day within a sentence
cal - Shows a calendar in the terminal
lsof -u joel - Gets the open files of the user joel
kill -9 `` lsof -t -u joel ` ``` - Kills all open files of the user joel
lsof -i :8090-9090 - Gets the connections between port 8090 and 9090
lsof -p 23619 - Gets the process of pid 23619
netstat -tulpn - Gets all ports in use
iftop - Shows network traffic
lspci | egrep -i 'network|ethernet' - List network interfaces
curl ip.sb - Shows the current ip
curl ifconfig.me - Shows the the current ip
sudo shutdown -h 19:05 "Some message..." - Shutdown at a specific time
sudo !! - Reruns to the previous command with sudo prepended
sudo systemctl start servicename - Starts a service using systemd
sudo systemctl stop servicename - Stops a service using systemd
sudo systemctl restart servicename - Restarts a service using systemd
sudo systemctl status servicename - Checks the status of a service using systemd
sudo systemctl enable servicename - Enables a service using systemd
sudo systemctl disable servicename - Disables a service using systemd
sudo systemctl edit servicename - Edits a systemd unit file with an overwrite
sudo journalctl -u servicename - Shows the logs of a servvice
crontab -e - Edits the cronjobs
htop - Shows the system resources as an alternative to top
btop - Shows the system resources as an alternative to top
ps -ef - Gets all processes
ps aux --sort=-%mem - Gets all processes and sorts them by memory
pgrep chrome - Helps to quickly find the process id of the chrome application
sudo lsof -i :3000 - Returns the process id of the application hodling the 3000 port
sort -u input.txt - Remove duplicates with sort command
awk '!a[$0]++ - Remove duplicates with awk command
tr 'a-z' 'A-Z' - Replaces lower case with upper case letters
tr -d '[:space:]' - Remove space characters, form feeds, new-lines, carriage returns, horizontal tabs, and vertical tabs
tr -d . - Remove . character from the string
sed -r 's/[xyz]+/_/g' - Remove some characters from the passed string
sed -i $'s/\r$//' filename - Replaces dos with unix line endings
grep -oh "\w*th\w*" * - Match some characters from the passed string
grep -rn /foobar/ -e text_to_find - Find a text in a directory resursively
echo "${s%%.*}" - Match some characters from the passed string
tac poem1.txt poem2.txt- Reverses the lines of a file line by line
paste poem1.txt poem2.txt - Combines the lines of files side by side line by line
diff file1 file2 - Compares two files line by line
tr - Translates characters into other characters
rev - Reverses characters on a line
awk and sed - General purpose transformers
pandoc -f markdown readme.md > readme.html - Converts markdown into html
echo -n "$x" - Adds a newline to the printed line
`echo "$x\c" - Adds a newline to the printed line
echo "4+2" | bc - Basic caluclator which adds 2 to 1
echo "abcd" | xxd -r -p | base64 - Turn a hex encoded string into a base64 encoded string
echo "foobar" | base64 --decode | od -t x1 -An - Turn a base64 encoded string into a hex encoded string
echo -ne "\x1e\x07" | od -t x1 - Turns a unicode bytes into a hex encoded string
truncate -s -1 file - Removes one byte from the file
cat example.json | jq '.' - Print a json file nicely formatted
cat example.json | jq '.[0]' - Print the first element of a json file nicely formatted
cat example.json | jq '.[0]["greeting"]' - Print the greeting element of the first element of a json file nicely formatted
cat example.json | jq --arg e "${variable}" '.data[$e] += ["test1"]' - Pass a variable or environment variable to jq to use it in a jq operation
jq <<< {} - Creates an empty json document
jq '."my_arg"="my_val"' <<< {} - Creates a json document containing only my_arg and my_val
$ command="sleep '5'; echo 'done here'"
$ jq --arg key "commands" --arg value "$command" '.[$key]=[$value]' <<< {}
Creates a json document containing a key and a value passed by arguments.
csvstack -g red,white -n type wine-{red,white}-clean.csv | 1
xsv select 2-,1 > wine.csv
Combines two csv files to a single file using xsv select as well as csvstack
in2csv input.xlsx > input.csv
Converts an excel file into csv file
exiftool '-filename<CreateDate' -d %y%m%d_%H%M%S%%-c.%%le * - Renames a list of pictures with respect to the exif date
convert -resize x16 -gravity center -crop 16x16+0+0 avatar.png -flatten -colors 256 -background transparent favicon.ico - Converts an image to a favicon
convert myfigure.png -resize 200x100 myfigure.jpg - Resizes a picture
for file in 202208*_*.jpg; convert $file -resize 1000x750 resized/$file - Converts files matching the pattern to a certain size
ps | awk '{print $1}' - Print the first column of each line
cat /etc/passwd | awk -F ":" '{print $1}' - Use a different column separator than space and print the first column
awk -F ":" '{print $1} /etc/passwd - A different notation to use a different column separator than space and print the first column
awk 'BEGIN{FS=":"; OFS="-"} print $1,$6,$7}' /etc/passwd - Replace a field separator with another field separator and print some columns
cat /etc/shells | awk -F "/" '/^\// {print $NF}' | uniq - Last field when searching for a pattern
df | awk '/\/dev\/loop/ {print $1 $4 + $5}' - Again awk but having a sum of $4 and $5
cat /etc/shells | awk 'length($0) > 7' - Print only the lines which have a first column length of longer than 7
awk 'BEGIN { for(i=1; i<=10; i++) print "The square root of",i,"is",i*i;}' - Kind of programming in AWK
cat /etc/shells | awk '{print substr($0,4)}' - Use the substr function of AWK
df | awk 'NR==7, NR==11 {print NR, $0}' | Print line 7 to 11 and print the line including the line number
ffmpeg -i input.mts -c:v copy -c:a copy -f mp4 output.mp4 - Converts a mts into a mp4 video
ffmpeg -i input.mp4 -vcodec libx265 -crf 30 output.mp4 - Convers a mts into a libx265 encoded video
openssl x509 -in keyname.pem -text - Prints the content of a certificate
openssl s_client -connect office.com:443 - Prints the remote certificates
openssl s_client -connect office.com:443 -proxy localhost:8080 - Prints the remote certificates using a proxy
ssh -f -N -D 127.0.0.1:8080 remoteserver - Creates a socks proxy for application level fowarding
curl --proxy socks5h://127.0.0.1:8080 https://remote.remoteserver - Requests a remote server via a socks proxy
tldr - Shows simplified and community-driven man pages
bat - Cat clone with syntax highlighting and git integration
bat -A file.csv - Pretty prints a csv and shows also non-printable characters
find /tmp -name 'foo.txt' - Search for a file called foo.txt
fd pattern - Search for a file with the pattern
sort -u - Sorts and removes duplicates
df -k - Shows disk usage information
lscpu - Shows CPU usage information
man hier - Shows a description of the file system hierarchy
uptime - Shows the uptime of the machine
watch docker ps - Watch a command
watch -n 5 echo "foobar" - Watch a command every 5 seconds
ls -1 | parallel echo - Parallel echo
parallel --jobs 2 ./slow.sh ::: {A..C} - Parallel execution of a slow shell script
cmp <file1> <file2> - Compares the difference between two files
comm <file1> <file2> - Find lines in common
script <filename> - Record a log of your terminal session
jot <number> - Generate test data with jot
uname -a - Shows kernel release information
h - Show list of mails
delete * - Delete all mails
smbpasswd -a username - Readd a user to reset the password
smbpasswd -U username - Change the password
if [[ $var ]]; then - var is set and not empty
if [[ ! $var ]]; then - var is not set or it is set to an empty string
Sets the number of commands in the history of the shell to 10000:
HISTFILE=~/.zsh_history
HISTSIZE=10000
SAVEHIST=10000
https://unix.stackexchange.com/questions/273861/unlimited-history-in-zsh