Commands using head sorted by votes

Commands using head (314)

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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 >

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List all files modified by a command

Often you run a command, but afterwards you're not quite sure what it did. By adding this prefix/suffix around [COMMAND], you can list any files that were modified. . Take a nanosecond timestamp: YYYY-MM-DD HH:MM:SS.NNNNNNNNN $ date "+%F %T.%N" . Find any files that have been modified since that timestamp: $ find . -newermt "$D" . This command currently only searches below the current directory. If you want to look elsewhere change the find parameter, e.g. $ find /var/log . -newermt "$D"

Convert seconds to [DD:][HH:]MM:SS

Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Shows size of dirs and files, hidden or not, sorted.

Enhanced version: fixes sorting by human readable numbers, and filters out non MB or GB entries that have a G or an M in their name.

Print Memory Utilization Percentage For a specific process and it's children

Change the name of the process and what is echoed to suit your needs. The brackets around the h in the grep statement cause grep to skip over "grep httpd", it is the equivalent of grep -v grep although more elegant.

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"

Create a new file

find out how many days since given date

Exactly the same number of characters, exactly the same results, but with bc

find external links in all html files in a directory list

Just a handy way to get all the unique links from inside all the html files inside a directory. Can be handy on scripts etc.

Insert the last argument of the previous command

for example if you did a: $ ls -la /bin/ls then $ ls !$ is equivalent to doing a $ ls /bin/ls

Repeatedly purge orphaned packages on Debian-like Linuxes

Upgraded Debian/Ubuntu/etc. systems may have a number of "orphaned" packages which are just taking up space, which can be found with the "deborphan" command. While you could just do "dpkg --purge $(deborphan)", the act of purging orphans will often create more orphans. This command will get them all in one shot.

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Commands using head (314)

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