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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

Commands using head from sorted by
Terminal - Commands using head - 254 results
mco ping | head -n -4 | awk '{print $1}' | sort
2014-06-24 18:20:16
User: mrwulf
Functions: awk head ping
Tags: sort awk HEAD mco mcollective marionette-collective
0
Up
Down
Show an alphabetized list of all mcollective nodes
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
du -a | sort -nr | head -10
2014-06-10 13:00:27
User: compguy925
Functions: du head sort
0
Up
Down
Find directories in pwd, get disk usage, sort results
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
psql -h <SERVER NAME HERE> -t -c 'SELECT version();' |head -1
2014-04-25 08:26:23
User: hxre
Functions: head
Tags: bash Linux postgresql
0
Up
Down
Get a PostgreSQL servers version

-t, --tuples-only print rows only

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
history |awk '{print $3}' |awk 'BEGIN {FS="|"} {print $1}'|sort|uniq -c |sort -rn |head -10
2014-04-20 06:40:56
User: cypggs
Functions: awk head sort uniq
0
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&#26368;&#24120;&#20351;&#29992;&#30340;10&#20010;&#21629;&#20196;

最常使用的10个命令

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
google() { Q="$@"; GOOG_URL='https://www.google.com/search?q='; AGENT="Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/33.0.1750.152 Safari/537.36" elinks -dump "${GOOG_URL}${Q//\ /+}" | grep "\*" | head -1 }
2014-04-17 07:37:25
User: runvnc
Functions: grep head
Tags: google
0
Up
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Return the one-liner google response for queries like "12*24" or "what time is it in the uk"
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
du -hsx * | sort -rh | head -10
2014-04-14 17:54:23
User: mirams
Functions: du head sort
Tags: disk usage folder folder size
3
Up
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Provide the ten largest subfolders in the current folder
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< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c${1:-16};echo;
2014-04-07 10:07:22
User: opexxx
Functions: head tr
0
Up
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16 Character Random Password

This snippet will produce an alpha-numeric 16 character password

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo $(sudo lshw -businfo | grep -B 1 -m 1 $(df "/path/to/file" | tail -1 | awk '{print $1}' | cut -c 6-8) | head -n 1 | awk '{print $1}' | cut -c 5- | tr ":" "-") | sudo tee /sys/bus/usb/drivers/usb/unbind
2014-04-06 12:06:29
User: tweet78
Functions: awk cut df echo grep head sudo tail tee tr
Tags: usb filename filepath
30
Up
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Given a file path, unplug the USB device on which the file is located (the file must be on an USB device !)

You have an external USB drive or key.

Apply this command (using the file path of anything on your device) and it will simulate the unplug of this device.

If you just want the port, just type :

echo $(sudo lshw -businfo | grep -B 1 -m 1 $(df "/path/to/file" | tail -1 | awk '{print $1}' | cut -c 6-8) | head -n 1 | awk '{print $1}' | cut -c 5- | tr ":" "-")

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VAR=$(head -5)
2014-04-05 13:45:18
User: rodolfoap
Functions: head
Tags: read stdin head,
-2
Up
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Multiline read

Reads n lines from stdin and puts the contents in a variable. Yes, I know the read command and its options, but find this logical even for one line.

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function brainwallet_exponent () { printf %s "$1"|sha256sum|head -c 64; }
2014-02-18 01:49:09
User: nixnax
Functions: head printf
Tags: openssl redirection substitution printf sha256 bitcoin brainwallet
5
Up
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Bitcoin Brainwallet Exponent Calculator

A bitcoin "brainwallet" is a secret passphrase you carry in your brain.

The Bitcoin Brainwallet Exponent Calculator is one of three functions needed to calculate the bitcoin PRIVATE key. Roughly, the formula is exponent = sha256 (passphrase)

Note that this is a bash function, which means you have to type its name to invoke it.

You can check the accuracy of the results here http://brainwallet.org

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cat /dev/urandom | env LC_CTYPE=C tr -dc a-zA-Z0-9 | head -c 16; echo
2014-02-05 15:04:07
User: yakovlev
Functions: cat env head tr
Tags: password random generate mac os x
2
Up
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Generate random password on Mac OS X

Feel free to put this in your ~/.profile:

random(){ cat /dev/urandom | env LC_CTYPE=C tr -dc $1 | head -c $2; echo; }

Then use it to generate passwords:

random [:alnum:] 16

Or DNA sequences:

random ACGT 256
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wget -q -O- http://bitinfocharts.com/markets/btc-e/btc-usd.html |grep -o -P 'lastTrade">([0-9]{1,})(.){0,1}[0-9]{0,}' |grep -o -P '(\d)+(\.){0,1}(\d)*' |head -n 1
2014-01-25 23:40:00
User: peter1337
Functions: grep head wget
Tags: wget grep bitcoin btc
0
Up
Down
grep BTC last trading price from BTC-E, but u can change it.. they got em all
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sysctl -a | grep boottime | head -n 1
2014-01-24 13:03:48
User: lgarron
Functions: grep head sysctl
Tags: osx
1
Up
Down
Find last reboot time

Specific to OSX.

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phpunit --log-json php://stdout | awk '$NF ~ '/,/' && $1 ~ /"(test|time)"/' | cut -d: -f2- | sed "N;s/\n/--/" | sed "s/,//"| awk 'BEGIN{FS="--"}; {print $2 $1}' | sort -r | head -n 5
2014-01-24 12:50:02
User: adri
Functions: awk cut head sed sort
Tags: PHP phpunit
0
Up
Down
PHPUnit: Show the 5 slowest tests with their runtime
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curl -s -k https://www.kernel.org/feeds/kdist.xml | sed -n -e 's@.*<guid>\(.*\)</guid>.*@\[email protected]' | grep 'stable' | head -1 | awk -F , '{print $3}'
2013-12-17 23:59:27
User: Wafelijzer
Functions: awk grep head sed
Tags: kernel
0
Up
Down
Get current stable kernel version string from kernel.org

Fetches latest stable release version from first entry between tags

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
wget "us.download.nvidia.com$(wget -qO- "$(wget -qO- "nvidia.com/Download/processFind.aspx?psid=95&pfid=695&osid=19&lid=1&lang=en-us"|awk '/driverResults.aspx/ {print $4}'|cut -d "'" -f2|head -n 1)"|awk '/url=/ {print $2}'|cut -d '=' -f3|cut -d '&' -f1)"
2013-11-21 03:04:59
User: lowjax
Functions: awk cut head wget
Tags: windows sed awk wget cut nvidia drivers x64 geforce
1
Up
Down
Download latest NVIDIA Geforce x64 Windows driver

Download latest NVIDIA Geforce x64 Windows7-8 driver from Nvidia's website. Pulls the latest download version (which includes beta). This is the "English" version. The following command includes a 'sed' line to replace "english" with "international" if needed. You can also replace the starting subdomain with "eu." "uk." and others. Enjoy this one liner! 1 character under the max :)

wget "us.download.nvidia.com$(wget -qO- "$(wget -qO- "nvidia.com/Download/processFind.aspx?psid=95&pfid=695&osid=19&lid=1&lang=en-us" | awk '/driverResults.aspx/ {print $4}' | cut -d "'" -f2 | head -n 1)" | awk '/url=/ {print $2}' | sed -e "s/english/international/" | cut -d '=' -f3 | cut -d '&' -f1)"
Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
base64 /dev/urandom | head -c 33554432 | split -b 8192 -da 4 - dummy.
2013-11-12 17:56:23
User: pdxdoughnut
Functions: head split
Tags: random split base64 dummy file, null file, test file /dev/urandom
10
Up
Down
Create a bunch of dummy text files

Avoiding a for loop brought this time down to less than 3 seconds on my old machine. And just to be clear, 33554432 = 8192 * 4086.

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for i in {1..4096}; do base64 /dev/urandom | head -c 8192 > dummy$i.rnd ; done
2013-11-12 00:36:10
User: pdxdoughnut
Functions: head
Tags: random base64 for loop dummy file, null file, test file /dev/urandom
1
Up
Down
Create a bunch of dummy text files

Using the 'time' command, running this with 'tr' took 28 seconds (and change) each time but using base64 only took 8 seconds (and change). If the file doesn't have to be viewable, pulling straight from urandom with head only took 6 seconds (and change)

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for i in `seq 1 4096`; do tr -dc A-Za-z0-9 </dev/urandom | head -c8192 > dummy$i.rnd; done
2013-11-11 21:27:15
User: TuxOtaku
Functions: head tr
Tags: random for loop dummy file, null file, test file /dev/urandom
1
Up
Down
Create a bunch of dummy text files
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echo $(< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c10)
2013-11-07 21:51:38
User: santizo
Functions: echo head tr
0
Up
Down
Generate a random password.

Uses urandom and tr to generate a random password. Change the value of head -c## for the lenght of the password.

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wget --no-check-certificate https://www.kernel.org/$(wget -qO- --no-check-certificate https://www.kernel.org | grep tar | head -n1 | cut -d\" -f2)
2013-11-07 18:46:14
User: glaudiston
Functions: cut grep head tar wget
0
Up
Down
Download current stable kernel version from kernel.org

Access www.kernel.org and download the last stable linux kernel release.

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find . -name '*pdf*' -print0 | xargs -0 ls -lt | head -20
2013-10-03 21:58:51
User: fuats
Functions: find head ls xargs
Tags: last, modfiied find xargs
1
Up
Down
Prints the latest modified files in a directory tree recursively

Sorts by latest modified files by looking to current directory and all subdirectories

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du -ah | sort -hr | head -n50 | cat -n
2013-10-01 10:16:13
User: rgregor
Functions: cat du head sort
0
Up
Down
Display a numbered list of 50 biggets files sorted by size (human readable)
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head -c 24 /dev/urandom | base64
2013-09-28 16:32:47
User: henix
Functions: head
Tags: random
0
Up
Down
Generate a random password 30 characters long

Use less random number resources and less commands

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shuf /usr/share/dict/words |grep "^[^']\{3,6\}$" |head -n4 | sed -e "s/\b\(.\)/\u\1/g" | tr -d '\n'; echo
2013-09-06 03:05:31
User: chijonutor
Functions: grep head sed tr
Tags: tr xkcd shuf
0
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Down
Generate an XKCD #936 style 4 word password

Took one of the samples, added capitalization and removes in between spaces.

The final "echo" is just for readability.

Cheers

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