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Commands using head from sorted by
Terminal - Commands using head - 229 results
for f in *.html; do head -n -1 $f > temp; cat temp > $f; rm temp; done
2009-10-12 12:49:18
User: Sunng
Functions: cat head rm
-1

Some malicious program appends a iframe or script tag to you web pages on some server, use this command to clean them in batch.

head -c10 <(echo $RANDOM$RANDOM$RANDOM)
2009-10-09 15:09:02
User: jgc
Functions: echo head
Tags: HEAD random
0

Makes use of $RANDOM environment variable.

tr -c -d 0-9 < /dev/urandom | head -c 10
head -c4 /dev/urandom | od -N4 -tu4 | sed -ne '1s/.* //p'
find ~/Music -daystart -mtime -60 -name *mp3 -printf "%T@\t%p\n" | sort -f -r | head -n 30 | cut -f 2
awk '{print $1}' /var/log/httpd/access_log | sort | uniq -c | sort -rnk1 | head -n 10
for x in `seq 0 25 $(curl "http://www.commandlinefu.com/commands/browse"|grep "Terminal - All commands" |perl -pe 's/.+(\d+),(\d+).+/$1$2/'|head -n1)`; do curl "http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/$x" ; done > a.txt
2009-08-27 11:02:53
User: SuperFly
Functions: grep head perl
4

'jot' does not come with most *nix distros, so we need to use seq to make it work. This version tested good on Fedora 11.

for x in `jot - 0 \`curl "http://www.commandlinefu.com/commands/browse"|grep "Terminal - All commands" |perl -pe 's/.+(\d+),(\d+).+/$1$2/'|head -n1\` 25`; do curl "http://www.commandlinefu.com/commands/browse/sort-by-votes/plaintext/$x" ; done >a.txt
2009-08-25 21:57:15
Functions: grep head perl
0

This is an extension of a previous command by satyavvd on 2009-07-23 12:04:02, but this one grabs the whole archive. Hard coded numbers in previous script capped number of commands that could be fetched. This one grabs them all regardless of how big the archive gets.

find / -type f -exec wc -c {} \; | sort -nr | head -100
mysql -u<user> -p<password> -s -e 'DESCRIBE <table>' <database> | tail -n +1 | awk '{ printf($1",")}' | head -c -1
randpw(){ < /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c${1:-16};echo;}
2009-08-07 07:30:57
User: frozenfire
Functions: head tr
3

Generates password consisting of alphanumeric characters, defaults to 16 characters unless argument given.

seq 1 12 | sed 1,5d ; seq 1 12 | head --lines=-5
2009-08-01 00:41:52
User: flux
Functions: head sed seq
Tags: sed tail HEAD fun
0

Strangely enough, there is no option --lines=[negative] with tail, like the head's one, so we have to use sed, which is very short and clear, you see.

Strangely more enough, skipping lines at the bottom with sed is not short nor clear. From Sed one liner :

# delete the last 10 lines of a file

$ sed -e :a -e '$d;N;2,10ba' -e 'P;D' # method 1

$ sed -n -e :a -e '1,10!{P;N;D;};N;ba' # method 2

echo -e "HEAD / HTTP/1.1\nHost: slashdot.org\n\n" | nc slashdot.org 80 | head -n5 | tail -1 | cut -f2 -d-
ls -t1 | head -n1 | xargs tail -f
shuf file.txt | head -n 1
sort -R file.txt | head -1
head -$(($RANDOM % $(wc -l < file.txt) +1 )) file.txt | tail -1
ran=$(head /dev/urandom | md5sum); MAC=00:07:${ran:0:2}:${ran:3:2}:${ran:5:2}:${ran:7:2}; sudo ifconfig wlan0 down hw ether $MAC; sudo ifconfig wlan0 up; echo ifconfig wlan0:0
2009-07-16 16:21:44
User: workingsmart
Functions: echo head ifconfig sudo
7

Next time you are leaching off of someone else's wifi use this command before you start your bittorrent ...for legitimate files only of course.

It creates a hexidecimal string using md5sum from the first few lines of /dev/urandom and splices it into the proper MAC address format. Then it changes your MAC and resets your wireless (wlan0:0).

S=`pidof skype`;grep heap /proc/$S/maps|cut -f1 -d' '|awk -F- '{print "0x" $1 " 0x" $2}'|xargs echo "du me t ">l;gdb -batch -p $S -x l>/dev/null 2>&1;strings t|grep \(smirk|head -n1
2009-06-26 20:03:17
User: alvieboy
Functions: awk cut echo grep head xargs
0

Skype has an internal regex which depicts the emoticons it supports. However you cannot simply search the binary file for it. This small 181 character line will do just that, provided skype is running. And of course, only works in linux.

ls -1t | head -n10
2009-06-23 12:15:12
User: wires
Functions: head ls
Tags: ls
7

order the files by modification (thanks stanishjohnd) time, one file per output line and filter first 10

for k in `git branch|perl -pe s/^..//`;do echo -e `git show --pretty=format:"%Cgreen%ci %Cblue%cr%Creset" $k|head -n 1`\\t$k;done|sort -r
2009-06-03 08:25:00
User: brunost
Functions: echo head perl sort
14

Print out list of all branches with last commit date to the branch, including relative time since commit and color coding.

for i in `du --max-depth=1 $HOME | sort -n -r | awk '{print $1 ":" $2}'`; do size=`echo $i | awk -F: '{print $1}'`; dir=`echo $i | awk -F: '{print $NF}'`; size2=$(($size/1024)); echo "$size2 MB used by $dir"; done | head -n 10
lynx -source http://www.commandlinefu.com/commands/random | sed 's/<[^>]*>//g' | head -1037 | tail -10 | sed -e 's/^[ \t]*//' | sed '/^$/d' | head -2
find . -name \*.mp3 -printf "%C+ %h/%f\n" | sort -r | head -n20 | awk '{print "\""$2"\""}' | xargs -I {} cp {} ~/tmp
2009-05-17 07:06:10
User: bkinsey
Functions: awk cp find head sort xargs
2

Change ~/tmp to the destination directory, such as your mounted media. Change -n20 to whatever number of files to copy. It should quit when media is full. I use this to put my most recently downloaded podcasts onto my phone.

find / \( -name "*.log" -o -name "*.mylogs" \) -exec ls -lrt {} \; | sort -k6,8 | head -n1 | cut -d" " -f8- | tr -d '\n' | xargs -0 rm
2009-05-10 10:45:48
User: ghazz
Functions: cut find head ls sort tr xargs
1

This works on my ubuntu/debian machines.

I suspect other distros need some tweaking of sort and cut.

I am sure someone could provide a shorter/faster version.