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Commands using awk from sorted by
Terminal - Commands using awk - 1,097 results
nmap -sP your network/submask | awk "/^Host/"'{ print $2 }'
2009-04-02 12:41:54
User: rauhmaru
Functions: awk
0
Up
Down
Display only hosts up in network

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

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
find ./ -not -type d | xargs wc -l | cut -c 1-8 | awk '{total += $1} END {print total}'
2009-04-01 15:14:15
User: benschw
Functions: awk cut find wc xargs
1
Up
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Recursive Line Count
Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
man beep | sed -e '1,/Note/d; /BUGS/,$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
Up
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Play musical notes from octave of middle C

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

Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
awk '{print > $3".txt"}' FILENAME
2009-03-31 15:14:13
User: alperyilmaz
Functions: awk
Tags: awk sorting redirection
2
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sorting file contents into individual files with awk

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

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
[[ $(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
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ensure your ssh tunnel will always be up (add in crontab)

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

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Up
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List SMTP connections by host

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

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
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Find brute force attempts on SSHd

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

Show sample output | Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Tags: sort awk uniq netstat cut
14
Up
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Number of open connections per ip.

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
Show sample output | Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
awk '/start_pattern/,/stop_pattern/' file.txt
2009-03-28 14:28:59
User: atoponce
Functions: awk
79
Up
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Display a block of text with AWK

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.

Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Up
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find an unused unprivileged TCP port

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

Show sample output | Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
2009-03-27 08:26:39
User: stuntdawg
Functions: awk cut echo grep ifconfig sleep
Tags: bash Linux ifconfig
10
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Measures download speed on eth0
Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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}')
2009-03-25 09:53:10
User: aramosf
Functions: arp awk grep route
Tags: Network Security
2
Up
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add static arp entry to default gateway, arp poison protection
Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
awk '{sum+=$1; sumsq+=$1*$1} END {print sqrt(sumsq/NR - (sum/NR)**2)}' file.dat
2009-03-24 21:56:40
User: kaan
Functions: awk
Tags: awk
6
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Display the standard deviation of a column of numbers with awk
Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
Tags: awk graph plotutils
2
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Quick plotting of a function

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.

Comments (3) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
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Display rows and columns of random numbers with awk

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.

Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
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Averaging columns of numbers

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.

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
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Fibonacci numbers with awk

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

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
seq 100 | awk '{sum+=$1} END {print sum}'
2009-03-24 20:30:40
User: kaan
Functions: awk seq
Tags: awk seq
4
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Calculating series with awk: add numbers from 1 to 100

"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
Show sample output | Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ps ax | grep <processname> | grep -v grep | awk '{print $1}' | sudo xargs kill -9
2009-03-24 19:52:47
User: copyhacker
Functions: awk grep kill ps sudo xargs
-5
Up
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Kill a bunch of processes with the same name
Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
/usr/sbin/arp -i eth0 | awk '{print $3}' | sed 1d
2009-03-24 18:53:26
User: prayer
Functions: awk sed
Tags: Network
-1
Up
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List nearbies
Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ps aux | grep 'httpd ' | awk {'print $2'} | xargs kill -9
2009-03-23 16:15:06
User: thisduck
Functions: awk grep kill ps xargs
Tags: kill
-5
Up
Down
kills all processes for a certain program e.g. httpd
Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
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
17
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Convert all MySQL tables and fields to UTF8

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.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
sudo zcat /var/log/auth.log.*.gz | awk '/Failed password/&&!/for invalid user/{a[$9]++}/Failed password for invalid user/{a["*" $11]++}END{for (i in a) printf "%6s\t%s\n", a[i], i|"sort -n"}'
2009-03-21 06:41:59
User: point_to_null
Functions: awk printf sudo zcat
Tags: Security awk brute force
21
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Brute force discover

Show the number of failed tries of login per account. If the user does not exist it is marked with *.

Show sample output | Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ropened='p4 opened | awk -F# "{print \$1}" | p4 -x - revert'
2009-03-20 11:10:47
User: Alexander
Functions: awk
Tags: p4 SCM Perforce
1
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Revert back all files currently checked out by Perforce SCM for edit
Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
alias opened='p4 opened | awk -F# "{print \$1}"'
2009-03-20 11:06:41
User: Alexander
Functions: alias awk
Tags: p4 SCM Perforce
0
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Print the list of all files checked out by Perforce SCM

Just type 'opened' and get all files currently opened for edit.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate