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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!

Top Tags



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.
  • » If you wish to use your user account, you will probably need to reset your password.
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
ifconfig | awk -F: '/inet addr:/ { sub(/\.[^.]+$/, "", $2); if (!seen[$2]++ && $2 != "127.0.0") print $2 }'
2016-09-01 14:02:43
User: chrismccoy
Functions: awk ifconfig
Tags: ifconfig awk

For machines that have many ip blocks spanning different Class C's, this will show which ones.

tail -v -f $(php -i | grep "^[ \t]*error_log" | awk -F"=>" '{ print $2; }' | sed 's/^[ ]*//g')
2016-08-31 12:13:31
User: paulera
Functions: awk grep sed tail

Runs "php -i", filter the error_log location, then watches it using "tail"

ps auxw | grep -E 'sbin/(apache|httpd)' | awk '{print"-p " $2}' | xargs strace -F
2016-08-04 10:59:58
User: gormux
Functions: awk grep ps strace xargs
Tags: awk grep ps strace

Will open strace on all apache process, on systems using sbin/apache (debian) or sbin/httpd (redhat), and will follow threads newly created.

while true; do A=$(ls -l FILE | awk '{print $5}'); sleep 1; B=$(ls -l FILE | awk '{print $5}'); echo -en "\r"$(($B-$A))" Bps"; done
2016-06-27 20:33:02
User: Zort
Functions: awk echo ls sleep

Muestra el crecimiento de un archivo por segundo.

Cambia el texto "FILE" por el nombre del archivo a monitorear.

Comando LS + AWK

awk '/CurrConns/{print $NF}' <<< "$(echo "show info" | sudo nc -U /var/lib/haproxy/stats)"
ps -u jboss -o nlwp= | awk '{ num_threads += $1 } END { print num_threads }'
ASN=32934; for s in $(whois -H -h riswhois.ripe.net -- -F -K -i $ASN | grep -v "^$" | grep -v "^%" | awk '{ print $2 }' ); do echo " blocking $s"; sudo iptables -A INPUT -s $s -j REJECT &> /dev/null || sudo ip6tables -A INPUT -s $s -j REJECT; done
ss -t -o state established '( dport = :443 || dport = :80 )'|grep tcp|awk '{ print $5 }'|sed s/:http[s]*//g|sort -u|netcat whois.cymru.com 43|grep -v "AS Name"|sort -t'|' -k3
function df_func { local dfts=$(ssh $1 "df -lP | tail -n +2 | sed 's/%//'"); echo $dfts | awk '$5 > 90 {exit 1}' > /dev/null; if [ $? == 1 ]; then echo -n "$1 "; echo $dfts | awk '$5 > 90 {printf "%s %d%%\n", $6, $5}'; fi }
awk -F= '/^(psk|id)/{print $2}' /etc/NetworkManager/system-connections/"$(iwgetid -r)"
ps -eo pmem,comm | grep java | awk '{sum+=$1} END {print sum " % of RAM"}'
2016-02-10 09:00:56
User: bugmenot
Functions: awk grep ps sum

This command will add up RAM usage of all processes whose name contains "java" and output the sum of percentages in HRF. Also, unlike the original #15430, it wont fail on processes with a usage of >9.9%.

Pleases note that this command wont work reliably in use cases where a significant portion of processes involved are using less than 0.1% of RAM, because they will be counted as "0", even though a great number of them could add up to significant amounts.

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

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

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

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

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


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:






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

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

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

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

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


use , as field separator


deletes all spaces


loops over all input fields and print their index and value


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

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.