What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again.

Delete that bloated snippets file you've been using and share your personal repository with the world. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

If you have a new feature suggestion or find a bug, please get in touch via http://commandlinefu.uservoice.com/

Get involved!

You can sign-in using OpenID credentials, or register a traditional username and password.

First-time OpenID users will be automatically assigned a username which can be changed after signing in.

Universal configuration monitoring and system of record for IT.

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for:



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!

Top Tags





Commands tagged awk from sorted by
Terminal - Commands tagged awk - 301 results
a=$(xwininfo |gawk 'BEGIN {FS="[x+ \t]*"} /-geometry/ {print int(($3+1)/2)*2"x"int(($4+1)/2)*2"+"$5"+"$6}') ; echo ${a} ; ffmpeg -f x11grab -s ${a} -r 10 -i :0.0 -sameq -f mp4 -s wvga -y /tmp/out.mpg
2012-08-31 14:48:41
User: dwygo
Functions: echo gawk

Now we can capture only a specific window (we have to chose by clicking on it)

ffmpeg complains about "Frame size must be a multiple of 2" so we calculate the upper even number with (g)awk trickery.

We remove the grep, we are already using (g)awk here ....why losing time with grep !!! ;)

tcpdump -ntr NAME_OF_CAPTURED_FILE.pcap 'tcp[13] = 0x02 and dst port 80' | awk '{print $4}' | tr . ' ' | awk '{print $1"."$2"."$3"."$4}' | sort | uniq -c | awk ' {print $2 "\t" $1 }'
sudo apt-get remove $(dpkg -l|awk '/^ii linux-image-/{print $2}'|sed 's/linux-image-//'|awk -v v=`uname -r` 'v>$0'|sed 's/-generic*//'|awk '{printf("linux-headers-%s\nlinux-headers-%s-generic*\nlinux-image-%s-generic*\n",$0,$0,$0)}')
2012-08-15 10:02:12
User: mtron
Functions: awk sed sudo

Remove old kernels (*-generic and *-generic-pae) via apt-get on debian/ubuntu based systems. Tested on ubuntu 10.04 - 12.04.

cat /dev/urandom|od -t x1|awk 'NR > line { pos=int(rand()*15)+2;printf("%s",$pos);line=NR+(rand()*1000);digits = digits+2 } digits == 64 { print("\n");exit }'
2012-08-14 19:02:00
User: jetdillo
Functions: awk cat exit od

Use this the next time you need to come up with a reasonably random bitstring, like for a WPA/WPA2 PSK or something. Takes a continuous stream of bytes coming from /dev/urandom, runs it through od(1), picking a random field ($0 and $1 excluded) from a random line and then prints it.

egrep '.*(("STATUS)|("HEAD)).*' http_access.2012.07.18.log | awk '{sum+=$11; ++n} END {print "Tot="sum"("n")";print "Avg="sum/n}'
2012-07-27 12:18:29
User: fanchok
Functions: awk egrep

Depending on your Apache access log configuration you may have to change the sum+=$11 to previous or next awk token.

Beware, usually in access log last token is time of response in microseconds, penultimate token is size of response in bytes. You may use this command line to calculate sum and average of responses sizes.

You can also refine the egrep regexp to match specific HTTP requests.

hostname -I
2012-07-18 19:43:48
User: bashfan
Functions: hostname
Tags: awk IP ip address

That's the easiest way to do it. -I (or capital i) display all network addresses of a host

ip -f inet a | awk '/inet / { print $2 }'
2012-07-18 15:13:10
User: BorneBjoern
Functions: awk
Tags: awk IP ip address

gives u each configured IP in a seperate line.

netstat -tn | grep :80 | awk '{print $5}'| grep -v ':80' | cut -f1 -d: |cut -f1,2,3 -d. | sort | uniq -c| sort -n
2012-06-26 08:29:37
User: krishnan
Functions: awk cut grep netstat sort uniq

cut -f1,2 - IP range 16

cut -f1,2,3 - IP range 24

cut -f1,2,3,4 - IP range 24

svn status | grep "^M" | while read entry; do file=`echo $entry | awk '{print $2}'`; echo $file; svn revert $file; done
2012-06-17 16:01:06
User: wsams
Functions: awk echo grep read

This command allows you to revert every modified file one-by-one in a while loop, but also after "echo $file;" you can do any sort of processing you might want to add before the revert happens.

awk -F'\t' '{print $0 >>$5.tsv}'
2012-05-16 18:18:16
User: pykler
Functions: awk
Tags: awk split tsv

Will split the std input lines into files grouped by the 5th column content.

cal 04 2012 | awk '{ $7 && X=$7 } END { print X }'
2012-05-06 23:43:21
User: flatcap
Functions: awk cal

If your locale has Monday as the first day of the week, like mine in the UK, change the two $7 into $6

echo `disklabel mfid1s4 | sed -n '$p' | awk '{print $2}'` / 1024 / 1024 | bc -l
cal 04 2012 | awk 'NF <= 7 { print $7 }' | grep -v "^$" | tail -1
2012-05-03 16:57:45
User: javidjamae
Functions: awk cal grep tail

This is a little trickier than finding the last Sunday, because you know the last Sunday is in the first position of the last line. The trick is to use the NF less than or equal to 7 so it picks up all the lines then grep out any empty lines.

lynx -dump http://www.cooks4arab.com | awk '/http/{print $2}' | egrep "^https{0,1}"
lynx -dump http://www.domain.com | awk '/http/{print $2}' | egrep "^https{0,1}"
for k in $(git branch | sed /\*/d); do echo "$(git log -1 --pretty=format:"%ct" $k) $k"; done | sort -r | awk '{print $2}'
2012-04-07 11:19:00
User: dahuie
Functions: awk echo sed sort
Tags: bash git sed awk

Simpler and without all of the coloring gimmicks. This just returns a list of branches with the most recent first. This should be useful for cleaning your remotes.

ps h --ppid $(cat /var/run/apache2.pid) | awk '{print"-p " $1}' | xargs sudo strace
2012-03-21 01:59:41
Functions: awk cat ps sudo xargs

Like the original version except it does not include the parent apache process or the grep process and adds "sudo" so it can be run by user.

curl -s mobile.twitter.com/search | sed -n '/trend_footer_list/,/\ul>/p' | awk -F\> '{print $3}' | awk -F\< '{print $1}' | sed '/^$/d'
2012-03-15 17:17:06
User: articmonkey
Functions: awk sed
Tags: twitter awk curl

Prints top 5 twitter topics. Not very well written at all but none of the others worked.

find /path/to/dir -iname "*.ext" -print0 | xargs -0 mplayer -really-quiet -cache 64 -vo dummy -ao dummy -identify 2>/dev/null | awk '/ID_LENGTH/{gsub(/ID_LENGTH=/,"")}{SUM += $1}END{ printf "%02d:%02d:%02d\n",SUM/3600,SUM%3600/60,SUM%60}'
2012-03-11 12:28:48
User: DarkSniper
Functions: awk find printf xargs

Improvement on Coderjoe's Solution. Gets rid of grep and cut (and implements them in awk) and specifies some different mplayer options that speed things up a bit.

awk 'FNR==100 {print;exit}' file
2012-03-04 20:25:57
User: Testuser_01
Functions: awk
Tags: awk time LINES

This will save parsing time for operations on very big files.

awk '{cmd="date --date=\""$1"\" +\"%Y/%m/%d %H:%M:%S\" "; cmd | getline convdate; print cmd";"convdate }' file.txt
2012-02-28 14:08:52
User: EBAH
Functions: awk

Convert readable date/time with `date` command

print "$(lsvg -Lo |xargs lsvg -L|grep "TOTAL PPs"|awk -F"(" '{print$2}'|sed -e "s/)//g" -e "s/megabytes/+/g"|xargs|sed -e "s/^/(/g" -e "s/+$/)\/1000/g"|bc ) GB"
2012-02-03 13:58:41

Not figured by me, but a colleague of mine.

See the total amount of data on an AIX machine.

sed -r 's/(\[|])//g' | awk ' { $1=strftime("%D %T",$1); print }'
2012-02-03 13:07:37
User: Zulu
Functions: awk sed
Tags: sed awk timestamp

It remove the square bracket and convert UNIX time to human readable time for all line of a stream (or file).

ps -fea | grep PATTERN | awk {'print $2'} | xargs kill -9
awk -F":" '!list[$3]++{print $3}' /etc/passwd