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Commands using awk from sorted by
Terminal - Commands using awk - 1,149 results
grep "install " /var/log/dpkg.log | awk '{print $4}' | xargs apt-get -y remove --purge
history|awk '{print $2}'|awk 'BEGIN {FS="|"} {print $1}'|sort|uniq -c|sort -r
2009-04-05 13:40:56
User: kayowas
Functions: awk sort uniq
7

It will return a ranked list of your most commonly-entered commands using your command history

find . -type f -size +25000k -exec ls -lh {} \; | awk '{ print $8 ": " $5 }'
nmap -sP your network/submask | awk "/^Host/"'{ print $2 }'
2009-04-02 12:41:54
User: rauhmaru
Functions: awk
0

This command will display only the hosts that are active in the network.

find ./ -not -type d | xargs wc -l | cut -c 1-8 | awk '{total += $1} END {print total}'
man beep | sed -e '1,/Note/d; /BUGS/,$d' | awk '{print $2}' | xargs -IX sudo beep -f X -l 500
2009-04-01 06:48:48
User: jnash
Functions: awk man sed sudo xargs
4

Are there any creative pieces of music that can be created using beep and the shell? I'd love to hear it!

awk '{print > $3".txt"}' FILENAME
2009-03-31 15:14:13
User: alperyilmaz
Functions: awk
2

This command will sort the contents of FILENAME by redirecting the output to individual .txt files in which 3rd column will be used for sorting. If FILENAME contents are as follows:

foo foo A foo

bar bar B bar

lorem ipsum A lorem

Then two files called A.txt and B.txt will be created and their contents will be:

A.txt

foo foo A foo

lorem ipsum A lorem

and B.txt will be

bar bar B bar

[[ $(COLUMNS=200 ps faux | awk '/grep/ {next} /ssh -N -R 4444/ {i++} END {print i}') ]] || nohup ssh -N -R 4444:localhost:22 user@relay &
2009-03-31 09:39:59
User: j0rn
Functions: awk nohup ps ssh
Tags: ssh cronjob
4

I find it ugly & sexy at the same time isn't it ?

cat /var/log/secure | grep smtp | awk '{print $9}' | cut -f2 -d= | sort | uniq -c | sort -n | tail
2009-03-30 15:49:54
User: empulse
Functions: awk cat cut grep sort uniq
-2

Searches /var/log/secure for smtp connections then lists these by number of connections made and hosts.

cat /var/log/secure | grep sshd | grep Failed | sed 's/invalid//' | sed 's/user//' | awk '{print $11}' | sort | uniq -c | sort -n
2009-03-30 15:48:24
User: empulse
Functions: awk cat grep sed sort sshd uniq
8

Searches the /var/log/secure log file for Failed and/or invalid user log in attempts.

netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n
2009-03-28 21:02:26
User: tiagofischer
Functions: awk cut netstat sort uniq
14

Here is a command line to run on your server if you think your server is under attack. It prints our a list of open connections to your server and sorts them by amount.

BSD Version:

netstat -na |awk '{print $5}' |cut -d "." -f1,2,3,4 |sort |uniq -c |sort -nr
awk '/start_pattern/,/stop_pattern/' file.txt
2009-03-28 14:28:59
User: atoponce
Functions: awk
80

I find this terribly useful for grepping through a file, looking for just a block of text. There's "grep -A # pattern file.txt" to see a specific number of lines following your pattern, but what if you want to see the whole block? Say, the output of "dmidecode" (as root):

dmidecode | awk '/Battery/,/^$/'

Will show me everything following the battery block up to the next block of text. Again, I find this extremely useful when I want to see whole blocks of text based on a pattern, and I don't care to see the rest of the data in output. This could be used against the '/etc/securetty/user' file on Unix to find the block of a specific user. It could be used against VirtualHosts or Directories on Apache to find specific definitions. The scenarios go on for any text formatted in a block fashion. Very handy.

netstat -atn | awk ' /tcp/ {printf("%s\n",substr($4,index($4,":")+1,length($4) )) }' | sed -e "s/://g" | sort -rnu | awk '{array [$1] = $1} END {i=32768; again=1; while (again == 1) {if (array[i] == i) {i=i+1} else {print i; again=0}}}'
2009-03-27 20:38:43
User: mpb
Functions: awk netstat sed sort
4

Some commands (such as netcat) have a port option but how can you know which ports are unused?

while true; do X=$Y; sleep 1; Y=$(ifconfig eth0|grep RX\ bytes|awk '{ print $2 }'|cut -d : -f 2); echo "$(( Y-X )) bps"; done
arp -s $(route -n | awk '/^0.0.0.0/ {print $2}') \ $(arp -n | grep `route -n | awk '/^0.0.0.0/ {print $2}'`| awk '{print $3}')
awk '{sum+=$1; sumsq+=$1*$1} END {print sqrt(sumsq/NR - (sum/NR)**2)}' file.dat
seq 0 0.1 20 | awk '{print $1, cos(0.5*$1)*sin(5*$1)}' | graph -T X
2009-03-24 21:46:59
User: kaan
Functions: awk seq
2

The arguments of "seq" indicate the starting value, step size, and the end value of the x-range. "awk" outputs (x, f(x)) pairs and pipes them to "graph", which is part of the "plotutils" package.

seq 6 | awk '{for(x=1; x<=5; x++) {printf ("%f ", rand())}; printf ("\n")}'
2009-03-24 21:33:38
User: kaan
Functions: awk printf seq
Tags: awk seq
3

Displays six rows and five columns of random numbers between 0 and 1. If you need only one column, you can dispense with the "for" loop.

awk '{sum1+=$1; sum2+=$2} END {print sum1/NR, sum2/NR}' file.dat
2009-03-24 21:22:14
User: kaan
Functions: awk
Tags: awk
2

This example calculates the averages of column one and column two of "file.dat". It can be easily modified if other columns are to be averaged.

seq 50| awk 'BEGIN {a=1; b=1} {print a; c=a+b; a=b; b=c}'
2009-03-24 20:39:24
User: kaan
Functions: awk seq
Tags: awk seq
13

Another combination of seq and awk. Not very efficient, but sufficiently quick.

seq 100 | awk '{sum+=$1} END {print sum}'
2009-03-24 20:30:40
User: kaan
Functions: awk seq
Tags: awk seq
4

"seq 100" outputs 1,2,..,100, separated by newlines. awk adds them up and displays the sum.

"seq 1 2 11" outputs 1,3,..,11.

Variations:

1+3+...+(2n-1) = n^2

seq 1 2 19 | awk '{sum+=$1} END {print sum}' # displays 100

1/2 + 1/4 + ... = 1

seq 10 | awk '{sum+=1/(2**$1)} END {print sum}' # displays 0.999023
ps ax | grep <processname> | grep -v grep | awk '{print $1}' | sudo xargs kill -9
/usr/sbin/arp -i eth0 | awk '{print $3}' | sed 1d
ps aux | grep 'httpd ' | awk {'print $2'} | xargs kill -9
mysql --database=dbname -B -N -e "SHOW TABLES" | awk '{print "ALTER TABLE", $1, "CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci;"}' | mysql --database=dbname &
2009-03-21 18:45:15
User: root
Functions: awk
Tags: mysql
18

This loops through all tables and changes their collations to UTF8. You should backup beforehand though in case some data is lost in the process.