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2011-03-12 - Confoo 2011 presentation
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Commands using awk from sorted by
Terminal - Commands using awk - 1,096 results
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.

git status --porcelain | awk '{print $2}' | xargs git add
2012-09-05 18:07:26
User: brandizzi
Functions: awk xargs

Uses the --porcelain option, which is garanteed to be stable among git versions and configurations - also, is way easier to parse.

git status|awk '/modified:/ { printf("git add %s\n",$3) }; NF ==2 { printf("git add %s\n",$2) }'|sh
2012-09-03 00:09:04
User: jetdillo
Functions: awk

I came up with this because I don't have a problem remembering the big major changes I made deep inside my tree for a specific feature or bugfix but always manage to forget the trivial stuff I tweaked or touched along the way that needs to get pushed as well.

SUBNET="192.168.41" ; diff -y <(nmap -sP -n ${SUBNET}.0/24 | grep ${SUBNET}. | awk '{print $5}' | sort -t"." -k4 -n) <(for i in $(seq 1 254); do echo ${SUBNET}.$i; done)
2012-08-28 09:11:18
User: michel_p
Functions: awk diff echo grep seq sort

The command will make it easy to determine free IP ranges in a crowded sub-net.

awk '!array[$1]++' file.txt
2012-08-23 21:04:51
User: bede
Functions: awk

Removes duplicates in the specified field/column while outputting entire lines. An elegant command for processing tab (or otherwise) delimited data.

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 }'
curl -s "http://subfusion.net/cgi-bin/quote.pl?quote=futurama&number=1" |awk '/<body><br><br><b><hr><br>/ {flag=1;next} /<br><br><hr><br>/{flag=0} flag {print}'
2012-08-17 20:57:28
User: wreck23
Functions: awk

Random Futurama quote from http://cubemonkey.net/quotes/. Change the quote= to change the quote source.

awk '{print $1}' /proc/net/dev|grep :|sed "s/:.*//g"
grep -e "[sh]d[a-l][0-9]\?" /proc/partitions | awk '{print $4}'
2012-08-17 13:15:46
User: kro
Functions: awk grep

grep -e "[sh]d[a-l]$" /proc/partitions | awk '{print $4}' # for disks only

grep -e "[sh]d[a-l][0-9]\+" /proc/partitions | awk '{print $4}' # for partitions only

screen -x $(screen -ls | awk 'NR == 2 { print $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.

wget --no-use-server-timestamps $(curl $(curl http://wallbase.cc/random/23/eqeq/1920x1080/0/100/20 | grep 'wallpaper/' | awk -F'"' '{print $2}' | head -n1) | grep -A4 bigwall | grep img | awk -F'"' '{print $2}'); feh --bg-center $(ls -1t | head -n1)
ps wwwwuax|awk '/command/ { printf("kill -9 %s\n",$2) }'|/bin/sh
2012-08-14 21:44:38
User: jetdillo
Functions: awk ps

Okay, commands like this are a bit of a personal peeve. awk(1) operates on a /pattern/ {action} paradigm and yet I see people leave out the /pattern/ portion of an awk command all the time, opting to use grep or sed instead. You'll save yourself some typing and time if you include the /pattern/ with your {action}.

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.

find . -type f -exec file '{}' + | grep shell | awk -F':' '{print $1}' | xargs chmod u+x
2012-08-09 18:53:08
User: llebegue
Functions: awk chmod file find grep xargs

Allows to change 'shell' compatible files execution bit even if their name is not *.sh

lsof -p `pidof pidgin` | awk '{ print $9 }'|egrep `hostname` | grep -o ">[^:]\+:" | tr -d ":>" | while read line; do host $line; done;
export PATH= $(echo $PATH | tr ':' '\n' | awk '!/matching string/' | paste -sd:)