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2011-03-12 - Confoo 2011 presentation
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Commands using head from sorted by
Terminal - Commands using head - 226 results
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
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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 (5) | 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
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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.

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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.

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
0
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

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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.

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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 (6) | 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
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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 (1) | 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 (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
(netstat -atn | awk '{printf "%s\n%s\n", $4, $4}' | grep -oE '[0-9]*$'; seq 32768 61000) | sort -n | uniq -u | head -n 1
2010-12-15 09:27:59
User: depesz
Functions: awk grep head netstat seq sort uniq
2
Up
Down
find an unused unprivileged TCP port

perl-less way

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function where(){ COUNT=0; while [ `where_arg $1~$COUNT | wc -w` == 0 ]; do let COUNT=COUNT+1; done; echo "$1 is ahead of "; where_arg $1~$COUNT; echo "by $COUNT commits";};function where_arg(){ git log $@ --decorate -1 | head -n1 | cut -d ' ' -f3- ;}
2010-12-08 15:41:39
User: noisy
Functions: cut echo head wc
Tags: git
0
Up
Down
telling you from where your commit come from

usage:

where COMMIT

for instance:

where 1178c5950d321a8c5cd8294cd67535157e296554

where HEAD~5

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echo `cat /dev/urandom | base64 | tr -dc "[:alnum:]" | head -c64`
2010-12-06 21:04:57
User: Dereckson
Functions: echo head tr
-1
Up
Down
create random string from /dev/urandom (or another length)

The same command, but with a base64 filter, more forgiving for special characters than tr.

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
echo `cat /dev/urandom |tr -dc "[:alnum:]" | head -c64`
2010-12-06 20:01:56
User: unixmonkey14859
Functions: echo head tr
1
Up
Down
create random string from /dev/urandom (or another length)
Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
( apache2ctl -t && service apache2 restart || (l=$(apache2ctl -t 2>&1|head -n1|sed 's/.*line\s\([0-9]*\).*/\1/'); vim +$l $(locate apache2.conf | head -n1)))
2010-11-26 18:12:08
User: cicatriz
Functions: head locate sed vim
Tags: apache apache2 services
3
Up
Down
Check apache config syntax and restart or edit the file

Checks the apache configuration syntax, if is OK then restart the service otherwise opens the configuration file with VIM on the line where the configuration fails.

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