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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 - 12,420 results
egrep -v '^\s*($|#)' $(git grep -l '#!/bin/.*sh' *) | wc -l
2016-02-15 11:15:48
User: Natureshadow
Functions: egrep grep wc
Tags: git grep count code

Uses git grep for speed, relies on a valid she-bang, ignores leading whitespace when stripping comments and blank lines

ps -eo pmem,comm | grep java | awk '{sum+=$1} END {print sum " % of RAM"}'
2016-02-10 09:00:56
User: bugmenot
Functions: awk grep ps sum

This command will add up RAM usage of all processes whose name contains "java" and output the sum of percentages in HRF. Also, unlike the original #15430, it wont fail on processes with a usage of >9.9%.

Pleases note that this command wont work reliably in use cases where a significant portion of processes involved are using less than 0.1% of RAM, because they will be counted as "0", even though a great number of them could add up to significant amounts.

adb shell "screencap -p | base64" | sed 's/\r$//' | base64 -d | display
2016-02-07 18:46:35
User: T4b
Functions: sed

Dependencies on phone: adb access, screencap command, base64 command.

Dependencies on computer: adb, sed, base64, display (from imagemagick, but can substitute other image viewer which reads from stdin).

This should work around adb stupidies (i.e. that it replaces \n with \r\n) with base64.

sudo system-image-cli --switch ubuntu-touch/rc-proposed/ubuntu --build 0
2016-02-07 18:24:28
User: bugmenot
Functions: sudo
Tags: ubuntu-phone

Get the latest and hopefully greatest to test out on the Ubuntu Phone - sometimes broken but always interesting. https://developer.ubuntu.com/en/start/ubuntu-for-devices/image-channels/

sudo mount -o remount,rw /
2016-02-07 17:57:19
User: bugmenot
Functions: mount sudo

Warning this will allow you to write to the system image on the phone, not recommended. But sometimes useful.

gsettings reset com.canonical.Unity.Dash favorite-scopes
2016-02-07 17:50:19
User: bugmenot
Functions: reset

To fix this bug: https://bugs.launchpad.net/ubuntu/+source/unity8/+bug/1389698

fortune | cowsay -f sodomized-sheep
wget https://open.uappexplorer.com/api/download/openstore.openstore-team/openstore.*_*_armhf.click && pkcon install-local --allow-untrusted openstore.*_*_armhf.click
2016-02-04 14:24:46
User: bugmenot
Functions: wget

This will download and install the latest version of the open store on the ubuntu phone, this store includes unconfined applications such as the TweakGeek and the Ubuntu Touch Tweak Tool. You can see the install instructions from here: https://open.uappexplorer.com/docs#install

ssh-keygen -b 4048 -t rsa -C "comment"
2016-02-03 09:37:39
User: erez83
Functions: ssh ssh-keygen
Tags: ssh centos

Generating ssh key

then need to copy public key in to /root/.ssh/authorized_keys

$if [[ "$(sleep 1 | telnet -c <host> <port> 2>&1 | grep '^SSH')" == SSH* ]]; then <command when up>; else <command when down>; fi;
2016-02-02 13:06:51
User: paulera

This command telnet and and looks for a line starting with "SSH" - works for OpenSSH since the SSH banner is something like "SSH-2.0-OpenSSH_6.0p1 Debian-4+deb7u3". Then it triggers an action accordingly.

It can be packed as a script file to echo 0/1 indicating the SSH service availability:

if [[ "$(sleep 1 | telnet -c <host> <port> 2>&1 | grep '^SSH')" == SSH* ]]; then echo 1; else echo 0; fi;

Alternative uses:

Trigger an action when server is UP (using &&):

[[ "$(sleep 1 | telnet -c <host> <port> 2>&1 | grep '^SSH')" == SSH* ]] && <command when up>

Trigger an action when server is DOWN (using ||):

[[ "$(sleep 1 | telnet -c <host> <port> 2>&1 | grep '^SSH')" == SSH* ]] || <command when down>
tcpdump -nqt -s 0 -A -i eth0 port 5060
ip=$(curl ip.pla1.net)
sudo strace -e trace=network -p `pidof nginx | sed -e 's/ /,/g'`
2016-01-28 18:48:16
Functions: sed strace sudo

Nginx (and other webservers like Apache) can be awkward to trace. They run as root, then switch to another user once they're ready to serve web pages. They also have a "master" process and multiple worker processes.

The given command finds the process IDs of all Nginx processes, joins them together with a comma, then traces all of them at once with "sudo strace." System trace output can be overwhelming, so we only capture "networking" output.

TIP: to kill this complex strace, do "sudo killall strace".

Compare with a similar command: http://www.commandlinefu.com/commands/view/11918/easily-strace-all-your-apache-processes

pacman -Ss python | paste - - | grep --color=always -e '/python' | less -R
2016-01-25 14:29:31
User: hute37
Functions: grep less paste python
Tags: less paste pacman

Alternative1 (grep support):

pacman -Ss python | paste - - | grep --color=always -e '/python' | less -R

Alternative2 (eye-candy, no grep):

pacman --color=always -Ss "python" | paste - - | less -R

in ~/.bashrc:

pkg-grep() { pacman -Ss "$1" | paste - - | grep --color=always -e "${2:-$1}" | less -R ; }

pkg-search() { pacman --color=always -Ss "python" | paste - - | less -R; }

ps -eo pmem,comm | grep chrome | cut -d " " -f 2 | paste -sd+ | bc
echo one 22 three | awk -F'[0-9][0-9]' '{print $2}'
get_iplayer --type=radio --channel "Radio 4 Extra" | grep : | awk '{ if ( NR > 1 ) { print } }'|sed 's/:.*//' |sed '$ d' > pidlist && while read p; do get_iplayer --get --fields=pid $p; done <pidlist && rm pidlist
2016-01-16 17:20:54
User: dunryc
Functions: awk grep read rm sed

use get_iplay to download all listed content from http://www.bbc.co.uk/radio4extra run every night to make sure no episodes are missed

openssl enc -d -aes-256-cbc -a -in bitcoin-wallet-backup -out bitcoin-wallet-backup-decrypted
stat -f '%Su' /dev/console
declare -a array=($(tail -n +2 /proc/net/tcp | cut -d":" -f"3"|cut -d" " -f"1")) && for port in ${array[@]}; do echo $((0x$port)); done
ffmpeg -loop 1 -i image.jpg -i audio.m4a -c:v libx264 -c:a aac -strict experimental -b:a 192k -vf scale=720:-1 -shortest video-output.mp4
[email protected]; tar -cf - /path/to/dir | pv | nc -l -p 6666 -q 5; [email protected]; nc 6666 | pv | tar -xf -
sajb {$ip="";$old=0;while(1){$up=test-connection -quiet -count 1 $ip;if($up-ne$old){$s=(date -u %s).split('.')[0]+' '+(date -f s).replace('T',' ')+' '+$ip+' '+$(if($up){'Up'}else{'Down'});echo $s|out-file -a $home\ping.txt;$old=$up}sleep 10}}

IMPORTANT: You need Windows PowerShell to run this command - in your Windows Command Prompt, type


Uses sajb to start a PowerShell background job that pings an IP host every 10 seconds.

Any changes in the host's Up/Down state is time-stamped and logged to a file.

Date/time stamps are logged in two formats: Unix and human-readable.

A while(1) loop repeats the test every 10 seconds by using the sleep command.

See the Sample Output for more detail.

I use this command to log Up/Down events of my Motorola SB6141 cable modem (

To end the logging, close the PowerShell window or use the "exit" command.

while(1){while((date -f ss)%10-gt0){sleep -m 300} echo "$(date -u %s) $((curl|%{$_ -replace '\D+\n',''})">>modemlog.txt;sleep 1;echo .}
2015-12-24 02:12:10
User: omap7777
Functions: date echo sleep

IMPORTANT: You need Windows PowerShell to run this command - in your Windows Command Prompt, type


Create a log file of your Motorola Surfboard SB6141 downstream signal strengths.

Uses the built-in curl to request signal strength data from your SB6141 cable modem.

HTML page has the signal strength numbers for the 8 downstreams.

Some HTML/DOM processing parses out the 8 values from the above page.

The eight extracted signal strengths are then logged to a file.

A small while-loop watches the clock & repeats the process every 10 seconds.

rsync -a --progress -e 'ssh -p 2200 -i .vagrant/machines/default/virtualbox/private_key' [email protected]:/vagrant/vm/old_timecapsule_backup /Volumes/2TB/
2015-12-17 15:28:12
User: brainstorm
Functions: rsync

That is, after running `vagrant ssh-config` to determine ports and ip's:

vagrant ssh-config

Host default


User vagrant

Port 2200

UserKnownHostsFile /dev/null

StrictHostKeyChecking no

PasswordAuthentication no

IdentityFile /Users/romanvg/tmp/.vagrant/machines/default/virtualbox/private_key

IdentitiesOnly yes

LogLevel FATAL