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2011-03-12 - Confoo 2011 presentation
Slides are available from the commandlinefu presentation at Confoo 2011: http://presentations.codeinthehole.com/confoo2011/
2011-01-04 - Moderation now required for new commands
To try and put and end to the spamming, new commands require moderation before they will appear on the site.
2010-12-27 - Apologies for not banning the trolls sooner
Have been away from the interwebs over Christmas. Will be more vigilant henceforth.
2010-09-24 - OAuth and pagination problems fixed
Apologies for the delay in getting Twitter's OAuth supported. Annoying pagination gremlin also fixed.




Commands using awk from sorted by
Terminal - Commands using awk - 1,111 results
for i in `seq 1 255`; do ping -c 1 10.10.10.$i | tr \\n ' ' | awk '/1 received/ {print $2}'; done
2009-08-22 09:34:27
User: hemanth
Functions: awk ping tr
Tags: ping

Ping sweep without NMAP

mailq | grep DrWEB | awk {'print $1'} | sed s/*//g | postsuper -d -
ps -ef | awk '/process-name/ && !/awk/ {print}'
2009-08-19 11:22:09
User: dopeman
Functions: awk ps

This does the same thing as many of the 'grep' based alternatives but allows a more finite control over the output. For example if you only wanted the process ID you could change the command:

ps -ef | awk '/mingetty/ && !/awk/ {print $2}'

If you wanted to kill the returned PID's:

ps -ef | awk '/mingetty/ && !/awk/ {print $2}' | xargs -i kill {}
mysql -u<user> -p<password> -s -e 'DESCRIBE <table>' <database> | tail -n +1 | awk '{ printf($1",")}' | head -c -1
awk < file.name '{ system("resolveip -s " $1) }'
2009-08-17 08:09:39
Functions: awk

Given a file of FQDN, this simple command resolves the IP addresses of those Useful for log files or anything else that outputs domain names.

FFPID=$(pidof firefox-bin) && lsof -p $FFPID | awk '{ if($7>0) print ($7/1024/1024)" MB -- "$9; }' | grep ".mozilla" | sort -rn
2009-08-16 08:58:22
User: josue
Functions: awk grep pidof sort

Check which files are opened by Firefox then sort by largest size (in MB). You can see all files opened by just replacing grep to "/". Useful if you'd like to debug and check which extensions or files are taking too much memory resources in Firefox.

egrep "^lease" /var/lib/dhcp/db/dhcpd.leases |awk '{ print $2 }'
2009-08-14 07:31:00
User: peshay
Functions: awk egrep

You can use that to create a excludefile for nmap, to find hosts, with no DHCP lease in your DHCP range.

echo $PATH|awk -F: ' { for (i=1; i <= NF; i++) print $i }'
awk -F ',' '{ x = x + $4 } END { print x }' test.csv
find . -name \*.pdf -exec pdfinfo {} \; | grep Pages | sed -e "s/Pages:\s*//g" | awk '{ sum += $1;} END { print sum; }'
ls -1 *.jpg | while read fn; do export pa=`exiv2 "$fn" | grep timestamp | awk '{ print $4 " " $5 ".jpg"}' | tr ":" "-"`; mv "$fn" "$pa"; done
2009-08-10 00:52:22
User: axanc
Functions: awk export grep ls mv read tr

Renames all the jpg files as their timestamps with ".jpg" extension.

awk /./ filename
2009-08-09 02:04:46
Functions: awk
Tags: awk

?Cat and grep? You can use only grep ("grep \. filename"). Better option is awk.

nslookup commandlinefu.com|sed 's/[^0-9. ]//g'|tail -n 1|awk -F " " '{print $2}'
2009-08-07 17:32:55
User: thundernode
Functions: awk nslookup sed tail

I use this in a script on my openwrt router to check if my DynDNS needs to be updated, saves your account from being banned for blank updates.

ifconfig | grep "0xffffffff" | awk '{ print $2 }' | xargs -n 1 ifconfig em0 delete
2009-08-04 05:18:36
User: vwal
Functions: awk grep ifconfig xargs

The example command deletes all aliases for network interface 'em0' assuming that the aliases have netmask of and the master IP has some other netmask (such as See here -> http://my.galagzee.com/2009/07/22/deleting-all-network-interface-aliases/ for more on the rationale of this command.

curl -s http://isc.sans.org/sources.html|grep "ipinfo.html"|awk -F"ip=" {'print $2'}|awk -F"\"" {'print $1'}|xargs -n1 sudo iptables -A OUTPUT -j DROP -d > 2&>1
du -aB1m|awk '$1 >= 100'
netstat -ant | grep :80 | grep ESTABLISHED | awk '{print $5}' | awk -F: '{print $1}' | sort | uniq -c | sort -n
ifconfig | awk '/ddr:[0-9]/ {sub(/addr:/, ""); print $2}'
2009-07-31 09:30:54
User: danny_b85
Functions: awk ifconfig
Tags: Linux ifconfig

The initial version of this command also outputted extra empty lines, so it went like this:

This happened on Ubuntu, i haven't tested on anything else.

ls foo*.jpg | awk '{print("mv "$1" "$1)}' | sed 's/foo/bar/2' | /bin/sh
svn ls -R | egrep -v -e "\/$" | xargs svn blame | awk '{print $2}' | sort | uniq -c | sort -r
2009-07-29 02:10:45
User: askedrelic
Functions: awk egrep ls sort uniq xargs
Tags: svn count

I'm working in a group project currently and annoyed at the lack of output by my teammates. Wanting hard metrics of how awesome I am and how awesome they aren't, I wrote this command up.

It will print a full repository listing of all files, remove the directories which confuse blame, run svn blame on each individual file, and tally the resulting line counts. It seems quite slow, depending on your repository location, because blame must hit the server for each individual file. You can remove the -R on the first part to print out the tallies for just the current directory.

ifconfig | awk -F':| +' '/ddr:/{print $4}'
2009-07-25 22:51:08
User: 0x89
Functions: awk ifconfig
Tags: Linux ifconfig

and, a lot uglier, with sed:

ifconfig | sed -n '/inet addr:/s/[^:]\+:\(\S\+\).*/\1/p'


Wanted to be shorter than the perl version. Still think that the perl version is the best..

cat /var/log/secure.log | awk '{print substr($0,0,12)}' | uniq -c | sort -nr | awk '{printf("\n%s ",$0) ; for (i = 0; i<$1 ; i++) {printf("*")};}'
2009-07-24 07:20:06
User: knassery
Functions: awk cat sort uniq

Busiest seconds:

cat /var/log/secure.log | awk '{print substr($0,0,15)}' | uniq -c | sort -nr | awk '{printf("\n%s ",$0) ; for (i = 0; i<$1 ; i++) {printf("*")};}'
awk '{print NR": "$0; for(i=1;i<=NF;++i)print "\t"i": "$i}'
2009-07-23 06:25:31
User: recursiverse
Functions: awk
Tags: awk

Breaks down and numbers each line and it's fields. This is really useful when you are going to parse something with awk but aren't sure exactly where to start.

$ awk '{ split(sprintf("%1.3e", $1), b, "e"); p = substr("yzafpnum_kMGTPEZY", (b[2]/3)+9, 1); o = sprintf("%f", b[1] * (10 ^ (b[2]%3))); gsub(/\./, p, o); print substr( gensub(/_[[:digit:]]*/, "", "g", o), 1, 4); }' < test.dat
2009-07-22 16:54:14
User: mungewell
Functions: awk
Tags: awk

converts any number on the 'stdin' to SI notation. My version limits to 3 digits of precious (working with 10% resistors).

curl -u 'username' https://api.del.icio.us/v1/posts/all | sed 's/^.*href=//g;s/>.*$//g;s/"//g' | awk '{print $1}' | grep 'http'
2009-07-22 07:32:59
User: bubo
Functions: awk grep sed

a variation of avi4now's command - thanks by the way!