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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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awk, bash, curl, find, grep, Linux, sed
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Maintained by Jon H.

Site originally by David Winterbottom (user root).

Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
  • » If you wish to use your user account, you will probably need to reset your password.
Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

All commands from sorted by
Terminal - All commands - 12,411 results
ASN=32934; for s in $(whois -H -h riswhois.ripe.net -- -F -K -i $ASN | grep -v "^$" | grep -v "^%" | awk '{ print $2 }' ); do echo " blocking $s"; sudo iptables -A INPUT -s $s -j REJECT &> /dev/null || sudo ip6tables -A INPUT -s $s -j REJECT; done
2016-04-08 11:30:12
User: koppi
Functions: awk echo grep iptables sudo whois
4
Up
Down
Block all FaceBook traffic
Comments (12) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ss -t -o state established '( dport = :443 || dport = :80 )' | grep -Po '([0-9a-z:.]*)(?=:http[s])' | sort -u|netcat whois.cymru.com 43|grep -v "AS Name"|sort -t'|' -k3
2016-04-08 09:07:39
User: miniker84
Functions: grep sort
0
Up
Down
Lookup autonomous systems of all outgoing http/s traffic

Using GNU Grep with perl regexp (works on newer Ubuntus)

Show sample output | Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ss -t -o state established '( dport = :443 || dport = :80 )'|grep tcp|awk '{ print $5 }'|sed s/:http[s]*//g|sort -u|netcat whois.cymru.com 43|grep -v "AS Name"|sort -t'|' -k3
2016-04-07 01:48:44
User: koppi
Functions: awk grep sed sort
3
Up
Down
Lookup autonomous systems of all outgoing http/s traffic
Show sample output | Comments (8) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
for i in *.flac; do flac -d -c "${i}" |lame -h --preset 196 --ta "Artist Here" --tl "Disc Title Here" --add-id3v2 - "./MP3/$i.mp3"; done
2016-04-06 13:39:52
User: arlequin
Tags: mp3 flac lame transcode
0
Up
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Transcode original FLAC files to downsampled MP3 files in exclusive folder

Make it better.

Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
function df_func { local dfts=$(ssh $1 "df -lP | tail -n +2 | sed 's/%//'"); echo $dfts | awk '$5 > 90 {exit 1}' > /dev/null; if [ $? == 1 ]; then echo -n "$1 "; echo $dfts | awk '$5 > 90 {printf "%s %d%%\n", $6, $5}'; fi }
2016-03-30 19:57:39
User: wytten12
Functions: awk echo ssh
Tags: bash function df
0
Up
Down
Reports file systems with disk usage exceeding 90% on the specified host
Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find . -type f -printf '%T@ %TY-%Tm-%Td %TH:%TM:%.2TS %p\n' | sort -nr | head -n 5 | cut -f2- -d" "
2016-03-23 11:56:39
User: paulera
Functions: cut find head sort
Tags: Linux modified files
6
Up
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List latest 5 modified files recursively

The output format is given by the -printf parameter:

%T@ = modify time in seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Mandatory, hidden in the end.

%TY-%Tm-%Td %TH:%TM:%.2TS = modify time as YYYY-MM-DD HH:MM:SS. Optional.

%p = file path

Refer to http://linux.die.net/man/1/find for more about -printf formatting.

------------------------

sort -nr = sort numerically and reverse (higher values - most recent timestamp - first)

head -n 5 = get only 5 first lines (change 5 to whatever you want)

cut -f2- -d" " = trim first field (timestamp, used only for sorting)

------------------------

Very useful for building scripts for detecting malicious files upload and malware injections.

Show sample output | Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
[ $[ $RANDOM % 6 ] == 0 ] && echo 'Bang!' || echo 'Click...'
2016-03-23 11:09:56
User: paulera
Functions: echo
Tags: bash fun
3
Up
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Safe Russian Roulette (only echo, don't delete files)

Shows "Bang!" in a chance of 1 out of 6, like in the original game with the gun (spin every round). Otherwise, echoes "Click...". If feeling brave you can also do:

[ $[ $RANDOM % 6 ] == 0 ] && echo 'Bang!' && a really killer command || echo 'Click...'
Show sample output | Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
fortune -s | cowsay -f tux | lolcat -s 64
2016-03-23 09:32:36
User: Zaphod
4
Up
Down
A rainbow-colored Tux gives a fortune cookie for the day. Great
Comments (8) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
make your terminal interactive and fun
2016-03-23 09:01:37
User: andreisid
Functions: make
0
Up
Down
bash | lolcat -a -s 250
Comments (21) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
transfer() { basefile=$(basename "$1" | sed -e 's/[^a-zA-Z0-9._-]/-/g');curl --progress-bar --upload-file "$1" "https://transfer.sh/$basefile"|xsel --clipboard;xsel --clipboard ; }
2016-03-20 19:38:48
User: leftyfb
Functions: basename sed
Tags: bash Debian Ubuntu curl clipboard
2
Up
Down
Easy file sharing from the command line using transfer.sh

Requires:

curl

xsel

access to the internet(http://transfer.sh)

This is an alias utilizing the transfer.sh service to make sharing files easier from the command line. I have modified the alias provided by transfer.sh to use xsel to copy the resulting URL to the clipboard.

The full modified alias is as follows since commandlinefu only allows 255 characters:

transfer() { if [ $# -eq 0 ]; then echo "No arguments specified. Usage:\necho transfer /tmp/test.md\ncat /tmp/test.md | transfer test.md"; return 1; fi if tty -s; then basefile=$(basename "$1" | sed -e 's/[^a-zA-Z0-9._-]/-/g'); curl --progress-bar --upload-file "$1" "https://transfer.sh/$basefile" |xsel --clipboard; else curl --progress-bar --upload-file "-" "https://transfer.sh/$1" |xsel --clipboard ; fi; xsel --clipboard; }

Show sample output | Comments (10) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
rsync -avxHAXW --info=progress2 /old-disk /new-disk/
2016-03-01 19:17:08
User: bugmenot
Functions: rsync
5
Up
Down
Copy the contents of one partition to another
Comments (9) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
awk -F= '/^(psk|id)/{print $2}' /etc/NetworkManager/system-connections/"$(iwgetid -r)"
2016-02-27 20:06:41
User: zlemini
Functions: awk
0
Up
Down
Display the SSID and password of the WIFI network you are currently connected to.
Comments (14) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
exa -glhrSuU -s size --group-directories-first -@ | less -R
2016-02-27 17:19:43
User: wires
Functions: less size
Tags: ls color exa
-1
Up
Down
exa

nothing fancy

`ls` alternative `exa`, with most info printed and passed through less with the `-R` (raw) option, to preserve colour output https://github.com/ogham/exa

You can add or remove `-@` to print extended attributes for files that have them.

Show sample output | Comments (10) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo /etc/*_ver* /etc/*-rel*; cat /etc/*_ver* /etc/*-rel*
2016-02-19 12:12:38
User: sxiii
Functions: cat echo
Tags: distribution package packages information
2
Up
Down
Show all the available information about your current distribution, package management and base

Just run this command and it will printout all the info available about your current distribution and package management system.

Show sample output | Comments (11) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
blank=$(mktemp -d); rsync --delete "$blank/" "bigdir/"; rmdir "$blank"
2016-02-15 11:23:15
User: Natureshadow
Functions: mktemp rmdir rsync
Tags: rsync rm
4
Up
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Recursively remove directory with many files quickly

rsync'ing an empty directory over a directory to be deleted recursively is much faster than using rm -rf, for various reasons. Relevant only for directories with really a lot of files.

Comments (12) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
0
Up
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Count relevant lines of shell code in a git repo

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

Show sample output | Comments (11) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Tags: memory usage ps
5
Up
Down
total percentage of memory use for all processes with a given name

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.

Show sample output | Comments (10) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
adb shell "screencap -p | base64" | sed 's/\r$//' | base64 -d | display
2016-02-07 18:46:35
User: T4b
Functions: sed
4
Up
Down
Takes and displays screenshot of Android phone over adb.

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.

Comments (10) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
0
Up
Down
Switch to rc-proposed channel on Ubuntu Phone - Nexus 4

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/

Comments (9) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
sudo mount -o remount,rw /
2016-02-07 17:57:19
User: bugmenot
Functions: mount sudo
Tags: mount ubuntu-phone
0
Up
Down
Make Ubuntu Phone root image read/write until reboot

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

Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
gsettings reset com.canonical.Unity.Dash favorite-scopes
2016-02-07 17:50:19
User: bugmenot
Functions: reset
Tags: gsettings ubuntu-phone
0
Up
Down
Reset the favorite-scopes on the Ubuntu Phone

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

Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
fortune | cowsay -f sodomized-sheep
2016-02-07 08:13:56
User: symgryph
0
Up
Down
Funny way to use cowsay to offend people
Comments (8) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Tags: wget ubuntu-phone
1
Up
Down
Download and install the OpenStore on the Ubuntu Phone

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

Show sample output | Comments (8) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ssh-keygen -b 4048 -t rsa -C "comment"
2016-02-03 09:37:39
User: erez83
Functions: ssh ssh-keygen
Tags: ssh centos
0
Up
Down
ssh-keygen -b 4048 -t rsa -C "comment"

Generating ssh key

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

Comments (12) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
$if [[ "$(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
Tags: status ssh bash Linux telnet server heartbeat
0
Up
Down
Test remote SSH server status using telnet (no login required)

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>
Comments (10) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate