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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
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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:

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Commands using head from sorted by
Terminal - Commands using head - 253 results
tr -dc A-Za-z0-9_ < /dev/urandom | head -c 10 | xargs
2012-10-17 14:04:14
User: nottings
Functions: head tr
7
Up
Down
generate a randome 10 character password
Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ps axo %mem,pid,euser,cmd | sort -nr | head -n 10
2012-10-12 03:27:26
User: lainme
Functions: head ps sort
0
Up
Down
Display the top ten running processes - sorted by memory usage

A nicer display from http://www.web-manual.net/linux-3/find-out-top-10-cpu-memory-consuming-processes/

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo $(</dev/urandom tr -dc 1-6 | head -c1)
2012-09-21 08:38:51
User: unixmonkey40000
Functions: echo head tr
Tags: password random /dev/random diceware
0
Up
Down
True Random Dice Roll
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tr -cd '1-6' < /dev/urandom | head -c 1; echo
2012-09-21 02:16:42
User: atoponce
Functions: head tr
Tags: password random /dev/random diceware
9
Up
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True Random Dice Roll

/dev/urandom is cryptographically secure, and indistinguishable from true random, as it gathers data from external sources, influenced by human timing interactions with computers, to fill the entropy pool, and hashes the input with SHA-1. As such, this is a quick way to do a "true random" fair-6 dice roll. Using this method, you could easily create passphrases with Diceware http://diceware.com.

Change the head(1) count to something other than 5 for more or less numbers.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
sudo -s du -sm /Users/* | sort -nr | head -n 10
2012-09-13 10:15:23
User: mematron
Functions: du head sort sudo
Tags: disk usage du users
1
Up
Down
Find the 10 users that take up the most disk space

In OSX you would have to make sure that you "sudo -s" your way to happiness since it will give a few "Permission denied" errors before finally spitting out the results. In OSX the directory structure has to start with the "Users" Directory then it will recursively perform the operation.

Your Lord and master,

Mematron

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
du -sh /home/*|sort -rh|head -n 10
2012-09-12 11:54:06
User: toaster
Functions: du head sort
Tags: disk usage sort du users
0
Up
Down
Find the 10 lusers winners of the "I take up the most disk space" award

the -h option of du and sort (on appropriate distrib) makes output "Human" readable and still sorted by "reversed size" (sort -rh)

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
du -sm /home/* | sort -nr | head -n 10
2012-09-11 13:09:22
User: dan
Functions: du head sort
Tags: disk usage du users
4
Up
Down
Find the 10 users that take up the most disk space
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find . -type f | xargs -I% bash -c 'echo -e "\033[31m%\033[0m" && [[ ! `file %` =~ .*binary.* ]] && head "%"'
2012-08-28 12:52:38
User: mx4492
Functions: bash find head xargs
0
Up
Down
Preview All Files in Directory
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wget --no-use-server-timestamps $(curl $(curl http://wallbase.cc/random/23/eqeq/1920x1080/0/100/20 | grep 'wallpaper/' | awk -F'"' '{print $2}' | head -n1) | grep -A4 bigwall | grep img | awk -F'"' '{print $2}'); feh --bg-center $(ls -1t | head -n1)
2012-08-14 22:06:27
User: yosh
Functions: awk grep head ls wget
0
Up
Down
Random (sfw, 1920x1080) wallpaper from wallbase.cc
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vlc $(for f in /proc/$(pgrep -f libflashplayer.so |head -n 1)/fd/*; do ;if $(file ${f} |grep -q "broken symbolic link to \`/tmp/FlashXX"); then echo ${f};fi;done)
2012-08-07 08:04:56
User: rtaycher
Functions: echo file grep head
0
Up
Down
Opens up cached flash plugin video files(linux)
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find . -type f -exec ls -shS {} + | head -10
2012-07-28 17:21:46
User: erichamion
Functions: find head ls
Tags: sort find GNU find file size
0
Up
Down
Find biggest 10 files in current and subdirectories and sort by file size

This requires a version of GNU find that supports the -exec {} + action, but it seems more straightforward than the versions already posted.

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for i in {1..10};do wget $(wget -O- -U "" "http://images.google.com/images?imgsz=xxlarge&hl=en&q=wallpaper+HD&start=$(($RANDOM%900+100))" --quiet | grep -oe 'http://[^"]*\.jpg' | head -1);done
2012-07-26 10:42:13
User: dzup
Functions: grep head wget
6
Up
Down
download 10 random wallpapers from google

you may want &hl=en for &hl=es for the language

you may want imgsz=xxlarge for imgsz=large or whatever filter

you may want q=apples or whatever

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ip a s eth0 | grep "inet " | head -n 1 | awk '{print $2}' | cut -f1 -d'/'
2012-07-16 07:54:43
User: thelan
Functions: awk cut grep head
Tags: IP
-4
Up
Down
Get the IP address

Get the first IPv4 address of an interface

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systemctl --failed | head -n -6 | tail -n -1
2012-07-11 22:31:46
User: corpix
Functions: head tail
0
Up
Down
Print failed units in systemd
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SEED=$(head -1 /dev/urandom|od -N 1);for i in {1..10};do tmp=$(mkpasswd ${RANDOM});pass=${tmp:2:6};echo Pass $pass Crypt: $(mkpasswd $pass);done
2012-07-07 03:20:46
User: dzup
Functions: echo head od
0
Up
Down
Show 10 6 characters pass and crypt(3) *if you like
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find . -type f -print0 | xargs -0 du -h | sort -hr | head -10
2012-06-30 10:03:31
User: netaxiz
Functions: du find head sort xargs
Tags: sort find file size
9
Up
Down
Find biggest 10 files in current and subdirectories and sort by file size
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
curl -s kernel.org | grep '<strong>' | head -3 | tail -1 | cut -d'>' -f3 | cut -d'<' -f1
2012-06-15 21:28:42
User: mdix
Functions: cut grep head tail
0
Up
Down
Get current stable kernel version string from kernel.org
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ps -e h -o pid --sort -pcpu | head -10 | vzpid -
2012-05-24 14:16:40
User: mrkmg
Functions: head ps
Tags: openvz
1
Up
Down
See OpenVZ Container id's of top 10 running processes by %cpu

This command will list the PID, VEID, and Name of the 10 highest cpu using processes on a openvz host. You must have vzpid installed.

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
wget -O - http://www.reddit.com/r/wallpapers.rss | grep -Eo 'http://i.imgur.com[^&]+jpg' | head -1 | xargs wget -O background.jpg
2012-04-25 11:15:26
User: untitaker
Functions: grep head wget xargs
0
Up
Down
set desktop background to highest-rated image from Reddit /r/wallpapers

Doesn't depend on curl and doesn't use thumbnails as wallpaper (which has the unfortunate effect of only allowing imgur links)

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(set -o noglob;while sleep 0.05;do for r in `grep -ao '[[:print:]]' /dev/urandom|head -$((COLUMNS/3))`;do [ $((RANDOM%6)) -le 1 ] && r=\ ;echo -ne "\e[$((RANDOM%7/-6+2));32m $r ";done;echo;done)
2012-04-13 02:09:10
User: khopesh
Functions: echo head set sleep
Tags: color screensaver Matrix Matrix Style
0
Up
Down
Matrix Style

A tweak using Patola's code as a base, this full-width green matrix display has all the frills (and all the printable characters).

You don't need the surrounding parens if you don't care about losing globbing capabilities. Z-shell (/bin/zsh) needs neither the parens nor the `set -o noglob`

Screen shot (animated): http://desmond.imageshack.us/Himg32/scaled.php?server=32&filename=matrixh.gif&res=landing

If it's too slow, try lowering the `sleep 0.05` or even replacing it with `true` (which is faster than `sleep 0`).

I squashed it as narrow as I could to conserve space, though somebody could probably squeeze a char or two out.

Enjoy!

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find . -type f -print0 | xargs -0 du -h | sort -hr | head -20
2012-03-30 10:21:12
User: flatcap
Functions: du find head sort xargs
Tags: sort find du xargs head,
9
Up
Down
Recursively find top 20 largest files (> 1MB) sort human readable format

Search for files and list the 20 largest.

find . -type f

gives us a list of file, recursively, starting from here (.)

-print0 | xargs -0 du -h

separate the names of files with NULL characters, so we're not confused by spaces

then xargs run the du command to find their size (in human-readable form -- 64M not 64123456)

| sort -hr

use sort to arrange the list in size order. sort -h knows that 1M is bigger than 9K

| head -20

finally only select the top twenty out of the list

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head -n1 nation.tbl | sed 's/\(.\)/\1\n/g' | sort | uniq -c | grep \| | awk '{ print $1 }'
2012-03-03 12:35:58
User: maarten
Functions: awk grep head sed sort uniq
0
Up
Down
Count Number of Columns in TPC-H table-file (or any pipe seperated file
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sed -e 's/[;|][[:space:]]*/\n/g' .bash_history | cut --delimiter=' ' --fields=1 | sort | uniq --count | sort --numeric-sort --reverse | head --lines=20
2012-02-17 23:34:16
User: WissenForscher
Functions: cut head sed sort uniq
Tags: bash sort sed uniq
1
Up
Down
Top 20 commands in your bash history
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for i in $(ps -eo pid,pmem,pcpu| sort -k 3 -r|grep -v PID|head -10|awk '{print $1}');do diff -yw <(pidstat -p $i|grep -v Linux) <(ps -o euser,pri,psr,pmem,stat -p $i|tail);done
2012-02-16 20:54:32
User: bob_the_builder
Functions: awk diff grep head ps sort
0
Up
Down
Displays user-defined ps output and pidstat output about the top CPU or MEMory users.

It grabs the PID's top resource users with $(ps -eo pid,pmem,pcpu| sort -k 3 -r|grep -v PID|head -10)

The sort -k is sorting by the third field which would be CPU. Change this to 2 and it will sort accordingly.

The rest of the command is just using diff to display the output of 2 commands side-by-side (-y flag) I chose some good ones for ps.

pidstat comes with the sysstat package(sar, mpstat, iostat, pidstat) so if you don't have it, you should.

I might should take off the timestamp... :|

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export GREP_COLOR='1;32';while [ true ]; do head -n 100 /dev/urandom; sleep .1; done | hexdump -C | grep --color=auto "ca fe"
2012-02-14 19:30:03
User: tbaschak
Functions: export grep head hexdump sleep true
2
Up
Down
pretend to be busy in office to enjoy a cup of coffee

combination of several of the above

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