Commands using head sorted by votes

Commands using head (314)

sorted by

20char long alpahnumeric "password"

20characters long alpahnumeric "password" Show Sample Output
This is sample output - yours may be different.
```
5698d846bfe078d67aef43fc0eebe4233401ad23
```
-1

head -c20 /dev/urandom | xxd -ps

opexxx · 2013-07-16 10:14:21 8
Get current stable kernel version string from kernel.org

Fetches latest stable release version from first entry between tags Show Sample Output
This is sample output - yours may be different.
```
3.12.5
```
-1

curl -s -k https://www.kernel.org/feeds/kdist.xml | sed -n -e 's@.*<guid>$.*$</guid>.*@\1@p' | grep 'stable' | head -1 | awk -F , '{print $3}'

Wafelijzer · 2013-12-17 23:59:27 7
Parse logs for IP addresses and how many hits from each IP
This is sample output - yours may be different.
-1

cat "log" | grep "text to grep" | awk '{print $1}' | sort -n | uniq -c | sort -rn | head -n 100

jmorganwalker · 2014-07-08 15:07:24 10
get line#1000 from text.
This is sample output - yours may be different.
-2

head -1000 < lines.txt | tail -1

wbx · 2009-02-08 06:41:20 15
Creates a random passwort from /dev/urandom [0-9A-za-z]

Replace < pw-length > with the desired password-length. The password-length is not always correct, but wayne...
This is sample output - yours may be different.
-2

head -c $((<pw-lenght>-2)) /dev/urandom | uuencode -m - | sed -e '1d' -e '3d' | sed -e 's/=.*$//g'

P17 · 2009-03-24 20:05:16 9
gzip vs bzip2 at compressing random strings?

Does that count as a win for bzip2? Show Sample Output
This is sample output - yours may be different.
```
$ \ls -l out*
-rw-r--r-- 1 chillu users 789711 2009-04-04 19:01 out.bz
-rw-r--r-- 1 chillu users 789947 2009-04-04 19:01 out.gz
```
-2

< /dev/urandom tr -dc A-Za-z0-9_ | head -c $((1024 * 1024)) | tee >(gzip -c > out.gz) >(bzip2 -c > out.bz) > /dev/null

jnash · 2009-04-04 13:23:01 11
Find the svn directory that a commit was made in. Usefull if you have many projects in one repository.
This is sample output - yours may be different.
-2

echo "12345,12346" |sed -e's/ //'|tr "," "\n"| while read line; do echo -n $line" "; svn log -vr $line https://url/to/svn/repository/|grep "/"|head -1|cut -d"/" -f2; done

psytek · 2009-04-15 15:21:20 4
print random commandlinefu.com submission

ok I'm sure it's not pretty Show Sample Output
This is sample output - yours may be different.
```
Terminal - runs a bash script in debugging mode    
bash -x ./post_to_commandlinefu.sh
```
-2

lynx -source http://www.commandlinefu.com/commands/random | sed 's/<[^>]*>//g' | head -1037 | tail -10 | sed -e 's/^[ \t]*//' | sed '/^$/d' | head -2

lxtips · 2009-06-02 09:48:59 11
Get name of first configured interface

Get the line containing "inet addr:" and the line before that, get down to only the first line, and then get the first word on that line, which should be the interface. Show Sample Output
This is sample output - yours may be different.
```
eth0
```
-2

ifconfig | grep -B 1 "inet addr:" | head -1 | cut -d" " -f1

jasonwalsh · 2010-01-04 23:02:57 5
List top ten files/directories sorted by size

If a directory name contains space xargs will do the wrong thing. Parallel https://savannah.nongnu.org/projects/parallel/ deals better with that. Show Sample Output
This is sample output - yours may be different.
```
33M     a b
17M     libxnee
3.6M    doc
3.0M    gnee
```
-2

du -s * | sort -nr | head | cut -f2 | parallel -k du -sh

unixmonkey8046 · 2010-01-28 12:59:14 6
Find MAC address of Active Eth connection
This is sample output - yours may be different.
-2

/sbin/ifconfig|grep -B 1 inet |head -1 | awk '{print $5}'

octopus · 2010-04-22 06:35:29 6
Set background image to random file from current dir.
This is sample output - yours may be different.
-2

feh --bg-center `ls -U1 |sort -R |head -1`

unixmonkey11903 · 2010-09-06 12:35:35 3
get a list of top 1000 sites from alexa

this will dump a list of domains one per line into a text file
This is sample output - yours may be different.
-2

curl -s -O http://s3.amazonaws.com/alexa-static/top-1m.csv.zip ; unzip -q -o top-1m.csv.zip top-1m.csv ; head -1000 top-1m.csv | cut -d, -f2 | cut -d/ -f1 > topsites.txt

chrismccoy · 2010-11-01 01:25:53 4
get newest file in current directory
This is sample output - yours may be different.
-2

ls -t1 | head -n1

altern · 2011-05-27 09:49:30 5
Grep with one result at a time

Not perfect but working (at least on the project i wrote it ;) ) Specify what you want search in var search, then it grep the folder and show one result at a time. Press enter and then it will show the next result. It can work bad on result in the firsts lines, and it can be improved to allow to come back. But in my case (a large project, i was checking if a value wasn't used withouth is corresponding const and the value is "1000" so there was a lot of result ...) it was perfect ;)
This is sample output - yours may be different.
-2

search="whatyouwant";data=$(grep "$search" * -R --exclude-dir=.svn -B2 -A2);for((i=$(echo "$data" | wc -l);$i>0;i=$(($i-6)) )); do clear;echo "$data"| tail -n $i | head -n 5; read;done

Juluan · 2011-08-29 18:14:16 4
Show the single most recently modified item in a directory

wrap it in a function if you like... lastfile () { ls -ltp | sed '1 d' | head -n1 } Show Sample Output
This is sample output - yours may be different.
```
-rw-r--r--    1 root     root           118 Dec 31  1969 default.prop
```
-2

ls -ltp | sed '1 d' | head -n1

linuxrawkstar · 2011-10-17 16:21:15 7
Get memory total from /proc/meminfo in Gigs

Probably more trouble than its worth, but worked for the obscure need.
This is sample output - yours may be different.
-2

memnum=$(awk '{ print $2 }' /proc/meminfo |head -n1); echo "$memnum / 1024 / 1024" | bc -l

wekoch · 2011-11-08 16:28:25 3
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. Show Sample Output
This is sample output - yours may be different.
```
$ A=$(head -3)
Line1
line2
line3

$ echo "$A"
Line1
line2
line3
```
-2

VAR=$(head -5)

rodolfoap · 2014-04-05 13:45:18 7
Generrate Cryptographically Secure RANDOM PASSWORD

Change :alnum: to :graph: for all printable characters Show Sample Output
This is sample output - yours may be different.
```
FH170AB1DXb4dHlX
```
-2

cat /dev/urandom |tr -c -d '[:alnum:]'|head -c 16;echo

AndrewM · 2019-06-17 17:51:04 36
Delete tens of thousans of files at one go

Deletes thousands of files at one go, I'm not able to recall the exact # of files that rm can delete at one go(apprx. around 7000.)
This is sample output - yours may be different.
-3

rm -rf `ls | head -5000`

rockon · 2009-02-25 22:52:23 7
Random password generating function

This uses urandom to produce a random password. The random values are uuencoded to ensure only printable characters. This only works for a number of characters between 1 and 60. Show Sample Output
This is sample output - yours may be different.
```
$ mkpasswd 56
AB:C[)\"=H#J:E()EY>HA6J,R741+ACL&08PC)P4Z#3R^YZ*3L0@O<<6
$ mkpasswd 9
YMO;<&.FB
```
-3

mkpasswd() { head -c $(($1)) /dev/urandom | uuencode - | sed -n 's/.//;2s/$.\{'$1'\}$.*/\1/p' ;}

taliver · 2009-11-19 14:27:52 5
Echo several blank lines
This is sample output - yours may be different.
-3

yes '' | head -n100

John_W · 2010-09-08 14:59:34 4
Selecting a random file/folder of a folder
This is sample output - yours may be different.
-3

echo Selected $(ls -1 | sort -R | head -n 1)

Juluan · 2011-03-13 22:06:54 3
open the last folder created
This is sample output - yours may be different.
-3

cd $(ls -1t --color=never | head -1)

tchepo · 2011-06-29 15:23:50 3
Cut a large wordlist into smaller chunks

Useful for situations where you have word lists or dictionaries that range from hundreds of megabytes to several gigabytes in size. Replace file.lst with your wordlist, replace 50000 with however many lines you want the resulting list to be in total. The result will be redirected to output.txt in the current working directory. It may be helpful to run wc -l file.lst to find out how many lines the word list is first, then divide that in half to figure out what value to put for the head -n part of the command.
This is sample output - yours may be different.
-3

less file.lst | head -n 50000 > output.txt

Richie086 · 2011-09-05 05:26:04 8
‹ First < 10 11 12 13 >

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands

Check These Out

Create a listing of all possible permissions and their octal representation.

Convert PDF to JPG

(relies on 'imagemagick') This command will convert all .pdf files in a directory into a 800px (wide or height, whichever is smaller) image (with the aspect ratio kept) .jpg. If the file is named 'example1.pdf' it will be named 'example1.jpg' when it is complete. This is a VERY worthwhile command! People pay hundreds of dollars for this in the Windows world. My .jpg files average between 150kB to 300kB, but your's may differ.

Deleting / Ignoring lines from the top of a file

Install pip with Proxy

Installs pip packages defining a proxy

Watch a movie in linux without the X windows system.

Read and write to TCP or UDP sockets with common bash tools

Ever needed to test firewalls but didn't have netcat, telnet or even FTP? Enter /dev/tcp, your new best friend. /dev/tcp/(hostname)/(port) is a bash builtin that bash can use to open connections to TCP and UDP ports. This one-liner opens a connection on a port to a server and lets you read and write to it from the terminal. How it works: First, exec sets up a redirect for /dev/tcp/$server/$port to file descriptor 5. Then, as per some excellent feedback from @flatcap, we launch a redirect from file descriptor 5 to STDOUT and send that to the background (which is what causes the PID to be printed when the commands are run), and then redirect STDIN to file descriptor 5 with the second cat. Finally, when the second cat dies (the connection is closed), we clean up the file descriptor with 'exec 5>&-'. It can be used to test FTP, HTTP, NTP, or can connect to netcat listening on a port (makes for a simple chat client!) Replace /tcp/ with /udp/ to use UDP instead.

Query an NFS host for its list of exports

translate what is in the clipboard in english and write it to the terminal

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

stringContains: Determining if a String Contains a Substring

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:

» all commands
» commands with 3 up-votes (commandlinefu3)
» commands with 10 up-votes (commandlinefu10)
» commands using head

Commands using head (314) the last day the last week the last month all time sorted by date votes

What's this?

Check These Out

Stay in the loop…

Commands using head (314)

sorted by