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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Terminal - All commands - 12,447 results
ffmpeg -re -y -i mm.mp4 -b:a 128k -vcodec libx264 -pix_fmt yuv420p -vf scale=640:480 -r 30 -g 60 -f flv "rtmp://rtmp-api.facebook.com:80/rtmp/xxxxxxxxxx"
2017-10-29 02:10:31
User: siamware

ffmpeg mp4 to facebook live steam

[command] 2> >(fb=$(dd bs=1 count=1 2>/dev/null | od -t o1 -A n); [ "$fb" ] && err=$(printf "\\${fb# }"; cat) && echo "ERROR - $err")
2017-10-16 22:22:42
User: tyzbit
Functions: dd echo od printf

This is a bit of a bash hack to catch STDERR and append a log level to it.

So for example, if your script has pseudo loglevels like so:

echo "INFO - finding files"

[ -f ${files} ] || echo "WARN - no files found"

Any subcommands that write to STDERR will screw that up

Adding 2> >(fb=$(dd bs=1 count=1 2>/dev/null | od -t o1 -A n); [ "$fb" ] && err=$(printf "\\${fb# }"; cat) && echo "ERROR - $err") to the command does the following:


Redirect STDERR


Spawn a subshell (STDERR is then redirected to the file descriptor for this subshell)


get the first byte of input

[ "$fb" ]

test if there's a first byte

&& err=$(printf....)

save the output to the $err variable

&& echo "ERROR - $err"

append your pseudo loglevel and the error message

Heavily borrowed from https://unix.stackexchange.com/questions/33049/check-if-pipe-is-empty-and-run-a-command-on-the-data-if-it-isnt

while [ true ]; do cat /proc/loadavg | perl -ne 'm/(^[^ ]+)/; $L = $1; print "*" x $L; print " $L\n";' ; sleep 6; done
2017-10-13 06:47:06
User: t3o
Functions: cat perl sleep true

It takes the first value of /prov/loadavg to print that many stars followed by the value.

dockpage() { lynx -width=180 --dump https://docs.docker.com/v1.11/engine/reference/commandline/$1/ | sed -n '/^Usage/,/On this page/{/On this page/b;p}'; }
2017-09-18 23:53:34
User: nnsense
Functions: sed

Docker's local man pages are (often) half of what you have online, so I wanted that as local man.

Install lynx and run my oneliner, then use as follows:


Adjust lynx's page width at will

alias dockps='docker ps --format "table {{.ID}}\t{{.Image}}\t{{.Status}}\t{{.Names}}"'
2017-09-18 23:46:47
User: nnsense
Functions: alias ps

Usefull, for example, when many ports are exposed and the docker ps output looks cluttered.

chage -M -1 root; echo "" > /etc/security/opasswd
2017-07-30 21:26:43
User: tsener
Functions: chage echo

Disable password expiration and clear password history for VMware vcenter appliance

socat "UNIX-LISTEN:/tmp/mysqld.temp.sock,reuseaddr,fork" EXEC:"ssh [email protected] socat STDIO UNIX-CONNECT\:/var/run/mysqld/mysqld.sock"
2017-07-27 11:32:19
User: paulera

Won't work with password login. You must add your RSA key to the server's authorizedkeys file, or change the ssh command adding the -i option for a custom RSA key:

socat "UNIX-LISTEN:/tmp/mysqld.temp.sock,reuseaddr,fork" EXEC:"ssh [email protected] -i /home/user/rsa-keys/id_rsa socat STDIO UNIX-CONNECT\:/var/run/mysqld/mysqld.sock"


/tmp/mysqld.temp.sock will be created locally by socat, don't create it yourself. The folder it lives must be writable. Connect your MySQL client to this socket, with database and username set properly.


In case you need to forward a remote socket to a LOCAL PORT instead, check http://www.commandlinefu.com/commands/view/9436/socat-tcp-listen5500-execssh-userremotehost-socat-stdio-unix-connectvarrunmysqldmysqld.sock

openssl rand -base64 12
numfmt --to=iec $[$(du -s /home/*/docs | cut -f 1 | paste -sd+)]
2017-07-15 00:53:20
User: odoepner
Functions: cut du paste

For example to add up the disk usage at several disjoint locations.

The $[..] is for arithmetic evaluation in bash.

Alternatively pipe to the bc command.

curlh() { x="$(curl -Is -w '%{http_code}' "[email protected]")"; if [[ "$(tail -n 1 <<< "$x")" == [45]* ]]; then curl -is "[email protected]" | awk '{ if (!NF) { exit }; print }'; else head -n -1 <<< "$x"; fi; }
2017-07-10 12:29:00
User: nyuszika7h
Functions: awk exit head

Some sites running on basic web servers don't support the HEAD request, so using "curl -I" on them doesn't work. This will automatically try "curl -I" at first and if that fails with a 4xx or 5xx status code, it falls back to "curl -i" and prints only the headers from that.

find . -name '*.log' | xargs ls -hlt > /tmp/logs.txt && vi /tmp/logs.txt
for domain in $(cat dominios.txt); do nslookup -type=mx $domain ; done >ejemplo.txt
grep -oP '(?<=www\.)\s?[^\/]*' file | uniq
2017-07-04 20:18:40
User: nedzoul
Functions: file grep

Obtener nombre de dominio de un archivo

csv2json() { for file in [email protected]; do python -c "import csv,json,fileinput; print(json.dumps(list(csv.reader(fileinput.input()))))" "$file" 1> "${file%%csv}json"; done; }
2017-06-28 04:28:32
User: snipertyler
Functions: file python
Tags: CSV python json

Based / Inspired by malathion's below command


Is written for python3 and is very easy to use

csv2json *csv will convert all files ending in csv to json

eg csv2json file.csv will output a file to file.json

Validity of json tested in python3 and below site


echo "$(obase=16; echo "$(date +%s)" | bc | xxd -r -p | base32)"
echo "http://commandlinefu.com" | curl -F-=\<- qrenco.de
phase() { while :; do for n in E4 F#4 B4 C#5 D5 F#4 E4 C#5 B4 F#4 D5 C#5; do /usr/bin/play -qn synth $1 pluck $n; done; echo -n "[$1]"; done; }; phase 0.13 & phase 0.131 &
2017-06-14 20:29:26
User: rodolfoap
Functions: echo

The Piano Phase piece, by Steve Reich is a minimalist composition which is played on two pianos played at slightly different tempos, a task that's very difficult to accomplish by human players. The auditive effects produced by the cell displacement produce beautiful patterns. See https://en.wikipedia.org/wiki/Piano_Phase . My rendered version: https://ydor.org/SteveReich/piano_phase.mp3

Requires sox to be installed on the system.

There are multiple videos on youtube showing different approaches and experiences to this interpretation. There is also a synthesized version.

Even if Bash can behave as a powerful pianist, a simple threaded version leaves full room to several time glitches and even negative displacements, the same issues that human pianists experience when playing the piece. The older the computer, the better the chaos added to the result due to the CPU load. Apparently that's the reason Steve Reich composes pieces such as this.

Without further ado, please give a warm welcome to the Bash minimalist player on synthesized two-threaded pianos. Please turn off your cellphones.

scrypt(){ [ -n "$1" ]&&{ echo '. <(echo "$(tail -n+2 $0|base64 -d|mcrypt -dq)"); exit;'>$1.scrypt;cat $1|mcrypt|base64 >>$1.scrypt;chmod +x $1.scrypt;};}
2017-06-14 16:27:20
User: rodolfoap
Functions: cat chmod echo

This function will encrypt a bash script and will only execute it after providing the passphrase. Requires mcrypt to be installed on the system.

cat hello


case "$1" in

""|-h) echo "This is the fantastic Hello World. Try this:" $(basename $0) "[entity]" ;;

moon) echo Good night. ;;

sun) echo Good morning. ;;

world) echo "Hello, world!" ;;

*) echo Hi, [email protected] ;;


scrypt hello

Enter the passphrase (maximum of 512 characters)

Please use a combination of upper and lower case letters and numbers.

Enter passphrase:

Enter passphrase:

Stdin was encrypted.

cat hello.scrypt

. <(echo "$(/usr/bin/tail -n+2 $0|base64 -d|mcrypt -dq)");exit;









This is the fantastic Hello World. Try this: hello [entity]


Enter passphrase:

This is the fantastic Hello World. Try this: hello.scrypt [entity]

./hello world

Hello, world!

./hello.scrypt world

Enter passphrase:

Hello, world!

bosh deployments --json | jq '.Tables[0].Rows[][0]' --raw-output
python -c "import csv,json;print json.dumps(list(csv.reader(open('csv_file.csv'))))"
2017-05-17 19:35:53
User: malathion
Functions: python
Tags: CSV python json

Replace 'csv_file.csv' with your filename.

ps aux | awk '{if ($8 ~ "D") print $0}'
find / -type d | while read i; do ls $i | wc -l | tr -d \\n; echo " -> $i"; done | sort -n
2017-05-12 00:02:43
User: Zort
Functions: echo find ls read sort tr wc

Show file count into directories.

Usefull when you try to find hugh directories that elevate system CPU (vmstat -> sy)

ffmpeg -i input.flv -vf scale=320:-1 -r 10 -f image2pipe -vcodec ppm - | convert -delay 5 -loop 0 - output.gif
2017-05-04 16:28:48
User: hadifarnoud

you can use any common video format. if you don't need to change the size of gif output, just remove `-vf scale=320:-1`

btw, 320:-1 means width is 320px and height would be set automatically

sudo systemctl mask sleep.target suspend.target hibernate.target hybrid-sleep.target
2017-04-28 19:49:36
User: symgryph
Functions: sudo

This causes computer to never power off or go into sleep mode. Disables sleep mode linux.

pmset -g batt | awk '/^ /{print $5}'