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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
March 2, 2015 - New Management
I'm Jon, I'll be maintaining and improving clfu. Thanks to David for building such a great resource!

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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

  • » The open beta is running a copy of the database that will not carry over to the final version. Don't post anything you don't mind losing.
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Your feedback is appreciated via the form on the beta page. Thanks! -Jon & CLFU Team

Commands using awk from sorted by
Terminal - Commands using awk - 1,210 results
sudo apt-get remove --purge `dpkg -l | awk '{print $2}' | grep gnome` && apt-get autoremove
2009-04-28 10:34:42
User: kelevra
Functions: awk grep sudo
Tags: awk apt-get dpkg

Useful for removes a package and its depends, for example to remove the gnome desktop environment, also configuration files will be removed, you should be carefully and sure that you want to do this.

ifconfig en1 | awk '/inet / {print $2}' | mail -s "hello world" [email protected]
2009-04-28 06:01:52
User: rez0r
Functions: awk ifconfig mail

This is useful if you have need to do port forwarding and your router doesn't assign static IPs, you can add it to a script in a cron job that checks if you IP as recently changed or with a trigger script.

This was tested on Mac OSX.

netstat -an | grep ESTABLISHED | awk '{print $5}' | awk -F: '{print $1}' | sort | uniq -c | awk '{ printf("%s\t%s\t",$2,$1) ; for (i = 0; i < $1; i++) {printf("*")}; print "" }'
2009-04-27 22:02:19
User: knassery
Functions: awk grep netstat sort uniq

Written for linux, the real example is how to produce ascii text graphs based on a numeric value (anything where uniq -c is useful is a good candidate).

awk 'BEGIN {srand()} {print int(rand()*1000000) "\t" $0}' FILE | sort -n | cut -f 2-
2009-04-19 20:04:58
User: udim
Functions: awk cut sort

Replace FILE with a filename (or - for stdin).

find /path/to/my/files/ -type f -name "*txt*" | xargs du -k | awk 'BEGIN{x=0}{x=x+$1}END{print x}'
2009-04-16 14:17:04
Functions: awk du find xargs

Use the find command to match certain files and summarise their total size in KBytes.

awk '/sshd/ && /Failed/ {gsub(/invalid user/,""); printf "%-12s %-16s %s-%s-%s\n", $9, $11, $1, $2, $3}' /var/log/auth.log
2009-04-16 00:56:23
User: frailotis
Functions: awk printf

A variation of a script I found on this site and then slimmed down to just use awk. It displays all users who have attempted to login to the box and failed using SSH. Pipe it to the sort command to see which usernames have the most failed logins.

/sbin/ifconfig -a | awk '/(cast)/ { print $2 }' | cut -d':' -f2 | head -1
find | sed -e "s/^.*\///" | awk ' BEGIN { FS=""} { print NF " " $0 } ' | sort -nrf | head -10
cd ~/.mozilla/firefox/ && sqlite3 `cat profiles.ini | grep Path | awk -F= '{print $2}'`/formhistory.sqlite "select * from moz_formhistory" && cd - > /dev/null
2009-04-13 20:23:37
User: klipz
Functions: awk cd grep

When you fill a formular with Firefox, you see things you entered in previous formulars with same field names. This command list everything Firefox has registered. Using a "delete from", you can remove anoying Google queries, for example ;-)

svn status | grep "^\?" | awk '{print $2}' | xargs svn add
svn status | grep '^?' | awk '{ print $2; }' | xargs svn add
2009-04-10 21:55:37
Functions: awk grep xargs
Tags: svn awk xargs

Lists the local files that are not present in the remote repository (lines beginning with ?)

and add them.

grep "install " /var/log/dpkg.log | awk '{print $4}' | xargs apt-get -y remove --purge
history|awk '{print $2}'|awk 'BEGIN {FS="|"} {print $1}'|sort|uniq -c|sort -r
2009-04-05 13:40:56
User: kayowas
Functions: awk sort uniq

It will return a ranked list of your most commonly-entered commands using your command history

find . -type f -size +25000k -exec ls -lh {} \; | awk '{ print $8 ": " $5 }'
nmap -sP your network/submask | awk "/^Host/"'{ print $2 }'
2009-04-02 12:41:54
User: rauhmaru
Functions: awk

This command will display only the hosts that are active in the network.

find ./ -not -type d | xargs wc -l | cut -c 1-8 | awk '{total += $1} END {print total}'
man beep | sed -e '1,/Note/d; /BUGS/,$d' | awk '{print $2}' | xargs -IX sudo beep -f X -l 500
2009-04-01 06:48:48
User: jnash
Functions: awk man sed sudo xargs

Are there any creative pieces of music that can be created using beep and the shell? I'd love to hear it!

awk '{print > $3".txt"}' FILENAME
2009-03-31 15:14:13
User: alperyilmaz
Functions: awk

This command will sort the contents of FILENAME by redirecting the output to individual .txt files in which 3rd column will be used for sorting. If FILENAME contents are as follows:

foo foo A foo

bar bar B bar

lorem ipsum A lorem

Then two files called A.txt and B.txt will be created and their contents will be:


foo foo A foo

lorem ipsum A lorem

and B.txt will be

bar bar B bar

[[ $(COLUMNS=200 ps faux | awk '/grep/ {next} /ssh -N -R 4444/ {i++} END {print i}') ]] || nohup ssh -N -R 4444:localhost:22 [email protected] &
2009-03-31 09:39:59
User: j0rn
Functions: awk nohup ps ssh
Tags: ssh cronjob

I find it ugly & sexy at the same time isn't it ?

cat /var/log/secure | grep smtp | awk '{print $9}' | cut -f2 -d= | sort | uniq -c | sort -n | tail
2009-03-30 15:49:54
User: empulse
Functions: awk cat cut grep sort uniq

Searches /var/log/secure for smtp connections then lists these by number of connections made and hosts.

cat /var/log/secure | grep sshd | grep Failed | sed 's/invalid//' | sed 's/user//' | awk '{print $11}' | sort | uniq -c | sort -n
2009-03-30 15:48:24
User: empulse
Functions: awk cat grep sed sort sshd uniq

Searches the /var/log/secure log file for Failed and/or invalid user log in attempts.

netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n
2009-03-28 21:02:26
User: tiagofischer
Functions: awk cut netstat sort uniq

Here is a command line to run on your server if you think your server is under attack. It prints our a list of open connections to your server and sorts them by amount.

BSD Version:

netstat -na |awk '{print $5}' |cut -d "." -f1,2,3,4 |sort |uniq -c |sort -nr
awk '/start_pattern/,/stop_pattern/' file.txt
2009-03-28 14:28:59
User: atoponce
Functions: awk

I find this terribly useful for grepping through a file, looking for just a block of text. There's "grep -A # pattern file.txt" to see a specific number of lines following your pattern, but what if you want to see the whole block? Say, the output of "dmidecode" (as root):

dmidecode | awk '/Battery/,/^$/'

Will show me everything following the battery block up to the next block of text. Again, I find this extremely useful when I want to see whole blocks of text based on a pattern, and I don't care to see the rest of the data in output. This could be used against the '/etc/securetty/user' file on Unix to find the block of a specific user. It could be used against VirtualHosts or Directories on Apache to find specific definitions. The scenarios go on for any text formatted in a block fashion. Very handy.

netstat -atn | awk ' /tcp/ {printf("%s\n",substr($4,index($4,":")+1,length($4) )) }' | sed -e "s/://g" | sort -rnu | awk '{array [$1] = $1} END {i=32768; again=1; while (again == 1) {if (array[i] == i) {i=i+1} else {print i; again=0}}}'
2009-03-27 20:38:43
User: mpb
Functions: awk netstat sed sort

Some commands (such as netcat) have a port option but how can you know which ports are unused?

while true; do X=$Y; sleep 1; Y=$(ifconfig eth0|grep RX\ bytes|awk '{ print $2 }'|cut -d : -f 2); echo "$(( Y-X )) bps"; done