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awk, bash, curl, find, grep, Linux, sed
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Functions

Commands using head from sorted by
Terminal - Commands using head - 256 results
head -n1 sample.txt | tail -n1
2011-06-14 17:45:04
User: gtcom
Functions: head tail
Tags: tail HEAD
0
Up
Down
Extract specific lines from a text file using Stream Editor (sed)

You can actually do the same thing with a combination of head and tail. For example, in a file of four lines, if you just want the middle two lines:

head -n3 sample.txt | tail -n2

Line 1 --\

Line 2 } These three lines are selected by head -n3,

Line 3 --/ this feeds the following filtered list to tail:

Line 4

Line 1

Line 2 \___ These two lines are filtered by tail -n2,

Line 3 / This results in:

Line 2

Line 3

being printed to screen (or wherever you redirect it).

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history | tail -(n+1) | head -(n) | sed 's/^[0-9 ]\{7\}//' >> ~/script.sh
2011-06-08 13:40:58
User: unixmonkey15842
Functions: head sed tail
Tags: history bash sed tail script
1
Up
Down
Create a bash script from last n commands

Uses history to get the last n+1 commands (since this command will appear as the most recent), then strips out the line number and this command using sed, and appends the commands to a file.

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find . -maxdepth 1 -printf '%[email protected]\t%p\n' | sort -r | cut -f 2,2 | head -1
2011-05-27 11:22:47
User: dullgiulio
Functions: cut find head sort
0
Up
Down
get newest file in current directory

Uses UNIX time for sorting.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ls -t1 | head -n1
2011-05-27 09:49:30
User: altern
Functions: head ls
-2
Up
Down
get newest file in current directory
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od /dev/urandom -w6 -tx1 -An|sed -e 's/ //' -e 's/ /:/g'|head -n 1
2011-05-16 15:05:34
User: karel1980
Functions: head od sed
2
Up
Down
Generat a Random MAC address

Just increase the 1 at the end if you want to generate more than one.

(Alternative to "| head -n N" you could use the -b flag of od: -b $[6*N]

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo $(( $( date +%s ) - $( stat -c %Y * | sort -nr | head -n 1 ) ))
2011-05-12 14:29:45
User: depesz
Functions: date echo head sort stat
Tags: bash awk stat mtime
-1
Up
Down
Show seconds since modified of newest modified file in directory
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alias screenr='screen -r $(screen -ls | egrep -o -e '[0-9]+' | head -n 1)'
2011-05-12 05:44:39
User: yababay
Functions: alias egrep head screen
0
Up
Down
Quick enter into a single screen session
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cut -f1 -d" " ~/.bash_history | sort | uniq -c | sort -nr | head -n 30
2011-04-25 04:40:33
User: AncientPC
Functions: cut head sort uniq
0
Up
Down
Show the most commonly used commands from .bash_history
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while true; do while [ `date +%H%M` == "1857" ] ; do sleep 1s; yes | head -n 2000 > /dev/dsp; done; done;
2011-04-23 14:44:26
User: mrwill
Functions: head sleep yes
-1
Up
Down
a simple alarm

this command will beep like an alarm for one minute from 18:57. you can change "1857" to your desired time.

you should have alsa-oss package installed, and you should also be root or part of "audio" group.

Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
function command_not_found_handle(){ apt-get install $( apt-file search "$1" | grep bin | grep -w "$1" | head -n1 | cut -d ':' -f 1 ) && $* ; }
2011-04-06 19:58:32
User: Juluan
Functions: cut grep head install
-7
Up
Down
Install and run when a command is not found

Work only with bash and apt-file installed.

When it found an unknow command, it will search for a file named "scribus" (in my example), in a folder named bin and then install the corresponding package.

After installation, it will run the command.

Usefull juste after reinstalling linux and missing lot of package.

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echo Selected $(ls -1 | sort -R | head -n 1)
2011-03-13 22:06:54
User: Juluan
Functions: echo head ls sort
Tags: sort random
-3
Up
Down
Selecting a random file/folder of a folder
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ps -eo pmem,pid,comm --no-headers | sort -k1 -rn | head -10
2011-03-11 04:51:35
User: dexterhu
Functions: head ps sort
0
Up
Down
show top 10 most memory hungry process with a simple format of (%mem, pid, short command)

Pros: the format is very simple, there is no need to show every columns, and full command with args

the first column is memory consumption %

the second column is pid

the third is just the command (without full arguments, most application's arguments are too long)

You can decide which application to kill then.

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env LC_CTYPE=C tr -dc "a-zA-Z0-9-_\$\?" < /dev/urandom | head -c 10
2011-02-22 17:09:44
User: aerickson
Functions: env head tr
Tags: password random generate mac os x
3
Up
Down
generate random password (works on Mac OS X)

Prepending

env LC_CTYPE=C

fixes a problem with bad bytes in /dev/urandom on Mac OS X

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
nice -n 5 electricsheep -window-id `xwininfo -root|head -n 2|grep xwininfo|cut -c 22-26`
2011-02-14 03:58:58
User: kbaegis
Functions: cut grep head nice
0
Up
Down
Animated Desktop: electricsheep

This is a simple command which makes electricsheep render directly to your background

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find . -type f -name '*.pm' -printf '%6s %p\n' | sort -nr | head -n 50
2011-02-09 16:19:11
User: depesz
Functions: find head sort
0
Up
Down
List 50 largest source files in a project

Will work with filenames with spaces inside. Will not break in case of someone making directory that matches *.pm. And sorts from largest. Where largest is file size, not line count.

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curl http://www.discogs.com/search?q=724349691704 2> /dev/null | grep \/release\/ | head -2 | tail -1 | sed -e 's/^<div>.*>\(.*\)<\/a><\/div>/\1/'
2011-01-30 23:45:50
User: mrman
Functions: grep head sed tail
Tags: sed grep curl discogs UPC
0
Up
Down
Find artist and title of a music cd, UPC code given (first result only)

Changed wget to curl and it doesn't create a file anymore.

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wget http://www.discogs.com/search?q=724349691704 -O foobar &> /dev/null ; grep \/release\/ foobar | head -2 | tail -1 | sed -e 's/^<div>.*>\(.*\)<\/a><\/div>/\1/' ; rm foobar
2011-01-30 23:34:54
User: TetsuyO
Functions: grep head rm sed tail wget
Tags: sed wget grep discogs UPC
-1
Up
Down
Find artist and title of a music cd, UPC code given (first result only)

Substitute that 724349691704 with an UPC of a CD you have at hand, and (hopefully) this oneliner should return the $Artist - $Title, querying discogs.com.

Yes, I know, all that head/tail/grep crap can be improved with a single sed command, feel free to send "patches" :D

Enjoy!

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while true; do lynx --dump http://whatthecommit.com/ | head -n 1 | cowsay; sleep 2; done
2011-01-27 14:36:12
User: linuxswords
Functions: head sleep
4
Up
Down
let the cow suggest some commit messages for you
Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
curl -s http://www.last.fm/user/$LASTFMUSER | grep -A 1 subjectCell | sed -e 's#<[^>]*>##g' | head -n2 | tail -n1 | sed 's/^[[:space:]]*//g'
2011-01-24 08:16:48
User: sn0opy
Functions: grep head sed tail
Tags: sed tail grep HEAD last.fm
-1
Up
Down
Fetch current song from last.fm
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ls -S|head -1find
2011-01-15 10:20:31
User: liyuance
Functions: head ls
1
Up
Down
find the biggest file in current folder
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finger | grep $(whoami) | head -n1 | awk '{print $2 " " $3}'
2011-01-07 16:54:11
User: mogoh
Functions: awk finger grep head
0
Up
Down
Prints out, what the users name, notifyed in the gecos field, is

finger - gets logged in users

grep $(whoami) - greps only the current user (if there are more logged in)

head -n1 - just one line

awk '{print $2 " " $3}' - second and third word, seperated with a space (the users name)

OT: My first commandlinefu-command :)

Show sample output | Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
seq -w 50 | sort -R | head -6 |fmt|tr " " "-"
2011-01-05 01:12:58
User: metalx1000
Functions: head seq sort tr
Tags: random range shuf
0
Up
Down
lotto generator
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find -type f | xargs -I{} du -s "{}" | sort -rn | head | cut -f2 | xargs -I{} du -sh "{}"
2011-01-04 11:10:56
User: glaudiston
Functions: cut du find head sort xargs
Tags: size find filesize
-1
Up
Down
Find the biggest files

Show the top file size in human readable form

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head -100000 /dev/urandom | strings|tr '[A-Z]' '[a-z]'|sort >temp.txt && wget -q http://www.mavi1.org/web_security/wordlists/webster-dictionary.txt -O-|tr '[A-Z]' '[a-z]'|sort >temp2.txt&&comm -12 temp.txt temp2.txt
2010-12-26 11:04:42
User: marssi
Functions: head sort tr wget
6
Up
Down
Look for English words in /dev/urandom

Little faster alternative.

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head -100000 /dev/urandom | strings > temp.txt && for w in $(cat webster-dictionary.txt); do if [ ${#w} -gt 3 ]; then grep -io $w temp.txt; fi; done
2010-12-23 01:58:56
User: rugina
Functions: cat grep head strings
6
Up
Down
Look for English words in /dev/urandom

* to get the English dictionary: wget http://www.mavi1.org/web_security/wordlists/webster-dictionary.txt

Show sample output | Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate