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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 - 1,112 results
echo /home/foo/dir1/bar | awk -F/ -v OFS=/ '{$3 = "dir2"}1'
2012-10-26 16:17:20
User: zlemini
Functions: awk echo

Awk replaces the value of a specific field while retaining the field separator "/" .

ls /var/log/sa/sa[0-9]*|xargs -I '{}' sar -u -f {}|awk '/^[0-9]/&&!/^12:00:01|RESTART|CPU/{print "%user: "$4" %system: "$6" %iowait: "$7" %nice: "$5" %idle: "$9}'|sort -nk10|head
awk '{word=(substr($0,index($0,"blah"),5));print word}'
for i in $(ps -eo pid|grep -v PID);do echo ""; echo -n "==$i== ";awk '/^read|^write/{ORS=" "; print}' /proc/$i/io 2>/dev/null; echo -n " ==$i=="; done|sort -nrk5|awk '{printf "%s\n%s %s\n%s %s\n%s\n\n",$1,$2,$3,$4,$5,$6}'
ls /var/log/sa/sa[0-9]*|xargs -I '{}' sar -q -f {}| awk '/Average/'|awk '{runq+=$2;plist+=$3}END{print "average runq-sz:",runq/NR; print "average plist-sz: "plist/NR}'
for i in `ls /var/log/sa/|grep -E "sa[0-9][0-9]"`;do echo -ne "$i -- ";sar -r -f /var/log/sa/$i|awk '{ printf "%3.2f\n",($4-$6-$7)*100/(3+$4)}'|grep -Eiv "average|linux|^ --|0.00|^-" |awk '{sum+=$1 }END{printf "Average = %3.2f%%\n",sum/NR}';done
echo "abcdefg"|awk 'BEGIN {FS="''"} {print $2}'
/sbin/ifconfig |awk '/bond|eth/{getline i;printf $0" ";printf "%s\n", i" "}'|awk '{print $1,substr($7,6)}'
echo 1268727836 | awk '{print strftime("%c",$1)}'
awk '{print NR "\t" $0}'
ompload() { wget -O- - "$1" --quiet|curl -# -F file1=@- http://ompldr.org/upload|awk '/Info:|File:|Thumbnail:|BBCode:/{gsub(/<[^<]*?\/?>/,"");$1=$1;print}';}
2012-10-19 22:54:55
User: dzup
Functions: awk wget

Like i said, i havent test it yet, all becouse my internet its soo slow, if you try and works please share, also be nice to do it using the direct url link.

a=$(stty -a -F /dev/tty1| awk -F'[ ;]' '/columns/ { print $9 }'); fold -w$a /dev/vcs1;echo
export proc=chrome && ps aux | grep $proc | grep -v grep |awk '{print $2}'
tshark -qr [cap] -z conv,tcp | awk '{printf("%s:%s:%s\n",$1,$3,$10)}' | awk -F: '{printf("%s %s %s\n",$1,$3,substr($5,1,length($5)-10))}' | sort | uniq -c | sort -nr
for P in $(mount | awk '/type nfs / {print $3;}'); do echo $P; sudo umount $P && sudo mount $P && echo "ok :)"; done
2012-10-14 22:39:58
User: amatix
Functions: awk echo mount sudo umount
Tags: Linux mount nfs

`mount -o remount` doesn't pick up new NFS options (eg. timeo, soft, retrans, etc) so you need to do a full mount/remount cycle. This one-liner makes it quick and easy :) Update your fstab with the new options, then run it.

netstat -tn | awk '($4 ~ /:22\s*/) && ($6 ~ /^EST/) {print substr($5, 0, index($5,":"))}'
NUMCPUS=`grep ^proc /proc/cpuinfo | wc -l`; FIRST=`cat /proc/stat | awk '/^cpu / {print $5}'`; sleep 1; SECOND=`cat /proc/stat | awk '/^cpu / {print $5}'`; USED=`echo 2 k 100 $SECOND $FIRST - $NUMCPUS / - p | dc`; echo ${USED}% CPU Usage
2012-10-02 03:57:51
User: toxick
Functions: awk echo sleep wc

Using the output of 'ps' to determine CPU usage is misleading, as the CPU column in 'ps' shows CPU usage per process over the entire lifetime of the process. In order to get *current* CPU usage (without scraping a top screen) you need to pull some numbers from /proc/stat. Here, we take two readings, once second apart, determine how much IDLE time was spent across all CPUs, divide by the number of CPUs, and then subtract from 100 to get non-idle time.

find . \( -iname '*.cpp' -o -iname '*.h' \) -exec wc -l {} \; | sort -n | cut --delimiter=. -f 1 | awk '{s+=$1} END {print s}'
2012-09-19 15:21:01
User: jecxjoopenid
Functions: awk cut find sort wc

Searches for *.cpp and *.h in directory structure, counts the number of lines for each matching file and adds the counts together.

awk '{a[$3]++} END {for(i in a) print i}' /var/log/squid/access.log
for file in `svn st | awk '{print $2}'`; do svn revert $file; done
function ptop(){ `ps -ef | grep $* | awk 'BEGIN{printf "top "}{printf "-p" $2 " " }'` }
for i in $(multipath -ll | grep "3PARdata,VV"|awk '{print $1}') ; do parted -a optimal /dev/mapper/$i --script -- mklabel gpt mkpart primary 1 -1 set 1 lvm on ; done
2012-09-12 15:30:36
User: mhs
Functions: awk grep set

`multipath -ll` requires Device Mapper multipath.conf configuration. And of course, replace "3PARdata,VV" with your disk array's SCSI vendor,LUN name.

- GPT partition table allows you to create >2TB partitions

sudo lastb | awk '{if ($3 ~ /([[:digit:]]{1,3}\.){3}[[:digit:]]{1,3}/)a[$3] = a[$3]+1} END {for (i in a){print i " : " a[i]}}' | sort -nk 3
2012-09-11 14:51:10
User: sgowie
Functions: awk lastb sort sudo

The lastb command presents you with the history of failed login attempts (stored in /var/log/btmp). The reference file is read/write by root only by default. This can be quite an exhaustive list with lots of bots hammering away at your machine. Sometimes it is more important to see the scale of things, or in this case the volume of failed logins tied to each source IP.

The awk statement determines if the 3rd element is an IP address, and if so increments the running count of failed login attempts associated with it. When done it prints the IP and count.

The sort statement sorts numerically (-n) by column 3 (-k 3), so you can see the most aggressive sources of login attempts. Note that the ':' character is the 2nd column, and that the -n and -k can be combined to -nk.

Please be aware that the btmp file will contain every instance of a failed login unless explicitly rolled over. It should be safe to delete/archive this file after you've processed it.

apt-popcon() { (echo \#rank; apt-cache search "$@" |awk '$1 !~ /^lib/ {print " "$1" "}') |grep -Ff- <(wget -qqO- http://popcon.debian.org/by_inst.gz |gunzip); }
2012-09-08 00:29:31
User: khopesh
Functions: apt awk echo grep wget

This will take the packages matching a given `apt-cache search` query (a collection of AND'd words or regexps) and tell you how popular they are. This is particularly nice for those times you have to figure out which solution to use for e.g. a PDF reader or a VNC client.

Substitute "ubuntu.com" for "debian.org" if you want this to use Ubuntu's data instead. Everything else will work perfectly.

top -n2 -d 0.5 | grep ^Cpu | sed 's/[[:alpha:]%]*//g' | awk 'NR == 2 {printf("%.2f\n",100-$5)}'
2012-09-06 12:56:26
User: wizzra
Functions: awk grep sed top

Get the current cpu % usage on your system.