Hide

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.
Hide

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:

Hide

News

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!
Hide

Top Tags

Hide

Functions

Commands using awk from sorted by
Terminal - Commands using awk - 1,202 results
echo one 22 three | awk -F'[0-9][0-9]' '{print $2}'
get_iplayer --type=radio --channel "Radio 4 Extra" | grep : | awk '{ if ( NR > 1 ) { print } }'|sed 's/:.*//' |sed '$ d' > pidlist && while read p; do get_iplayer --get --fields=pid $p; done <pidlist && rm pidlist
2016-01-16 17:20:54
User: dunryc
Functions: awk grep read rm sed
0

use get_iplay to download all listed content from http://www.bbc.co.uk/radio4extra run every night to make sure no episodes are missed

for f in `git status | grep new | awk '{print $3}'`; do git reset HEAD $f ; done
s3cmd du s3://bucket-name | awk '{print $0/1024/1024/1024" GB"}'
awk 'BEGIN{srand()} match($0, /DELTA=([0-9]+);/, a) {w[i++]=a[1]} END {print w[int(rand()*i)]}' file.name
2015-11-13 17:56:34
User: jkirchartz
Functions: awk
Tags: awk regex random
0

seed the random number generator,

find all matches in a file

put all matches from the capture group into an array

return a random element from the array

F=bigdata.xz; lsof -o0 -o -Fo $F | awk -Ft -v s=$(stat -c %s $F) '/^o/{printf("%d%%\n", 100*$2/s)}'
2015-09-19 22:22:43
User: flatcap
Functions: awk stat
6

Imagine you've started a long-running process that involves piping data,

but you forgot to add the progress-bar option to a command.

e.g.

xz -dc bigdata.xz | complicated-processing-program > summary

.

This command uses lsof to see how much data xz has read from the file.

lsof -o0 -o -Fo FILENAME

Display offsets (-o), in decimal (-o0), in parseable form (-Fo)

This will output something like:

.

p12607

f3

o0t45187072

.

Process id (p), File Descriptor (f), Offset (o)

.

We stat the file to get its size

stat -c %s FILENAME

.

Then we plug the values into awk.

Split the line at the letter t: -Ft

Define a variable for the file's size: -s=$(stat...)

Only work on the offset line: /^o/

.

Note this command was tested using the Linux version of lsof.

Because it uses lsof's batch option (-F) it may be portable.

.

Thanks to @unhammer for the brilliant idea.

while cat energy_now; do sleep 1; done |awk -v F=$(cat energy_full) -v C=60 'NR==1{P=B=$1;p=100/F} {d=$1-P; if(d!=0&&d*D<=0){D=d;n=1;A[0]=B=P}; if(n>0){r=g=($1-B)/n;if(n>C){r=($1-A[n%C])/C}}; A[n++%C]=P=$1; printf "%3d %+09.5f %+09.5f\n", p*$1, p*g, p*r}'
2015-09-19 15:45:40
User: sqweek
Functions: awk cat printf sleep
-1

Needs to be run in a battery sysfs dir, eg. /sys/class/power_supply/BAT0 on my system.

Displays the battery's current charge and the rate per-second at which energy is {dis,}charging. All values are displayed as percentages of "full" charge.

The first column is the current charge. The second is the rate of change averaged over the entire lifetime of the command (or since the AC cable was {un,}plugged), and the third column is the rate of change averaged over the last minute (controlled by the C=60 variable passed to awk).

The sample output captures a scenario where I ran 'yes' in another terminal to max out a CPU. My battery was at 76% charge and you can see the energy drain starts to rise above 0.01% per-second as the cpu starts working and the fan kicks in etc. While idle it was more like 0.005% per-second.

I tried to use this to estimate the remaining battery life/time until fully charged, but found it to be pretty useless... As my battery gets more charged it starts to charge slower, which meant the estimate was always wrong. Not sure if that's common for batteries or not.

pidstat -t | sed 's/,/./4' | awk -v seuil='10.0' '{if (NR>3 && $8>seuil) print }'
while true; do date; ps auxf | awk '{if($8=="D") print $0;}'; sleep 1; done
last|grep `whoami`|grep -v logged|cut -c61-71|sed -e 's/[()]//g'|awk '{ sub("\\+", ":");split($1,a,":");if(a[3]){print a[1]*60*60+a[2]*60+a[3]} else {print a[1]*60+a[2] }; }'|paste -s -d+ -|bc|awk '{printf "%dh:%dm:%ds\n",$1/(60*60),$1%(60*60)/60,$1%60}'
2015-09-19 03:02:43
User: donjuanica
Functions: awk cut grep last paste sed
-1

Add -n to last command to restrict to last num logins, otherwise it will pull all available history.

sudo lsof -nP | awk '/deleted/ { sum+=$8 } END { print sum }'
2015-09-19 00:45:23
Functions: awk sudo sum
0

A potential source of a full filesystem are large files left open but have been deleted. On Linux, a file may be deleted (removed/unlinked) while a process has it open. When this happens, the file is essentially invisible to other processes, but it still takes on physical space on the drive. Tools like du will not see it.

du -x --max-depth=1|sort -rn|awk -F / -v c=$COLUMNS 'NR==1{t=$1} NR>1{r=int($1/t*c+.5); b="\033[1;31m"; for (i=0; i<r; i++) b=b"#"; printf " %5.2f%% %s\033[0m %s\n", $1/t*100, b, $2}'|tac
2015-09-12 10:36:49
Functions: awk du printf sort
9

A more efficient way, with reversed order to put the focus in the big ones.

awk -F, '{gsub(/ /,"");for(f=1;f<=NF;f++) print f,$f;exit}' file.csv
2015-08-26 09:30:43
User: sesom42
Functions: awk
-1

-F,

use , as field separator

gsub()

deletes all spaces

for(){}

loops over all input fields and print their index and value

exit

exit after first line

head -1 file.csv | tr ',' '\n' | tr -d " " | awk '{print NR,$0}'
2015-08-26 05:46:15
User: neomefistox
Functions: awk head tr
0

Useful to identify the field number in big CSV files with large number of fields. The index is the reference to use in processing with commands like 'cut' or 'awk' involved.

curl - https://graph.facebook.com/fql?q=SELECT%20like_count,%20total_count,%20share_count,%20click_count,%20comment_count%20FROM%20link_stat%20WHERE%20url%20=%20%27<URL>%27 | awk -F\" '{ print $7 }' | awk -F":" '{ print $2 }' | awk -F"," '{ print $1 }'
2015-08-19 20:01:15
User: sxiii
Functions: awk
1

Replace the with your URL, for example http://rublacklist.net/12348/ and it will show likes number

sudo lsof | egrep 'w.+REG' | awk '{print $10}' | sort | uniq -c | sort -n
2015-08-18 14:09:02
User: kennethjor
Functions: awk egrep sort sudo uniq
1

This command run fine on my Ubuntu machine, but on Red Hat I had to change the awk command to `awk '{print $10}'`.

pyt() { id=$(curl -s 'https://www.youtube.com/results?search_query='$(tr \ + <<<"$1") | grep -om3 '"[[:alnum:]]\{11\}"' | awk NR==3 | tr -d \"); youtube-dl -q 'https://www.youtube.com/watch?v='"$id" -o - | mplayer -vo null /dev/fd/3 3<&0 </dev/tty; }
2015-07-20 05:30:27
User: snipertyler
Functions: awk grep tr
4

pyt 'Stairway to heaven - Led Zeppelin'

pyt 'brain damage - Pink Floyd'

No web browser or even X needed. Just a cli and internet connection!

mplayer is pauseable and can skip ahead

This may break if youtube changes their search html.

xmlpager() { xmlindent "$@" | awk '{gsub(">",">'`tput setf 4`'"); gsub("<","'`tput sgr0`'<"); print;} END {print "'`tput sgr0`'"}' | less -r; }
2015-07-12 09:22:10
User: hackerb9
Functions: awk less
0

Don't want to open up an editor just to view a bunch of XML files in an easy to read format? Now you can do it from the comfort of your own command line! :-) This creates a new function, xmlpager, which shows an XML file in its entirety, but with the actual content (non-tag text) highlighted. It does this by setting the foreground to color #4 (red) after every tag and resets it before the next tag. (Hint: try `tput bold` as an alternative). I use 'xmlindent' to neatly reflow and indent the text, but, of course, that's optional. If you don't have xmlindent, just replace it with 'cat'. Additionally, this example shows piping into the optional 'less' pager; note the -r option which allows raw escape codes to be passed to the terminal.

awk '{for(i=2;i<=NF;i++) printf("%s%s",$i,(i!=NF)?OFS:ORS)}'
awk '{ $1="";print}'
for p in $(pgrep -t $(cat /sys/class/tty/tty0/active)); do d=$(awk -v RS='\0' -F= '$1=="DISPLAY" {print $2}' /proc/$p/environ 2>/dev/null); [[ -n $d ]] && break; done; echo $d
2015-05-18 20:01:20
User: geyslan
Functions: awk cat echo
Tags: display xorg
1

It's useful when you cannot access your env (systemd) or the process DISPLAY variable is not set. Perhaps also when you have a multi-head/user configuration.

showip() { nmcli connection show $1|grep ipv4.addresses|awk '{print $2}' ; }
2015-05-13 16:24:28
User: nnsense
Functions: awk grep
1

Sometimes it's useful to output just the ip address. Or some other information, changing the "ipv4.addresses" in command. The power of awk! Show all possible "greps" with

nmcli connection show [yourInterfaceNameHere]
grep page.php /var/log/httpd/access_log|awk '{print $1}'|sort|uniq|perl -e 'while (<STDIN>){chomp; $cmd=`ipset add banned -! -q $_`; }'
mosth() { history | awk '{CMD[$2]++;count++;}END { for (a in CMD)print CMD[a] " " CMD[a]/count*100 "% " a;}' | grep -v "./" | column -c3 -s " " -t | sort -nr | nl | head -n10; }
2015-05-11 17:41:55
User: nnsense
Functions: awk column grep head nl sort
0

I copied this (let's be honest) somewhere on internet and I just made it as a function ready to be used as alias. It shows the 10 most used commands from history. This seems to be just another "most used commands from history", but hey.. this is a function!!! :D

wget -q -O- https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/ | grep Linux/7/pdf | cut -d \" -f 2 | awk '{print "https://access.redhat.com"$1}' | xargs wget