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Commands tagged awk

Commands tagged awk from sorted by
Terminal - Commands tagged awk - 216 results
sudo apt-get remove --purge `dpkg -l | awk '{print $2}' | grep gnome` && apt-get autoremove
2009-04-28 10:34:42
User: kelevra
Functions: awk grep sudo
Tags: awk apt-get dpkg
-3
Up
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Remove packages by pattern on debian and based systems

Useful for removes a package and its depends, for example to remove the gnome desktop environment, also configuration files will be removed, you should be carefully and sure that you want to do this.

Show sample output | Comments (6) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
ifconfig en1 | awk '/inet / {print $2}' | mail -s "hello world" email@email.com
2009-04-28 06:01:52
User: rez0r
Functions: awk ifconfig mail
Tags: ifconfig awk macosx IP osx mac email
8
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sends your internal IP by email

This is useful if you have need to do port forwarding and your router doesn't assign static IPs, you can add it to a script in a cron job that checks if you IP as recently changed or with a trigger script.

This was tested on Mac OSX.

Comments (4) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
svn status | grep '^?' | awk '{ print $2; }' | xargs svn add
2009-04-10 21:55:37
User: unixmonkey4200
Functions: awk grep xargs
Tags: svn awk xargs
1
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sync svn working copy and remote repository (auto adding new files)

Lists the local files that are not present in the remote repository (lines beginning with ?)

and add them.

Show sample output | Comments (2) | 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

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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
12
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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 (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
3
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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.

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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
12
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Fibonacci numbers with awk

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

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seq 100 | awk '{sum+=$1} END {print sum}'
2009-03-24 20:30:40
User: kaan
Functions: awk seq
Tags: awk seq
3
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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
cat file.txt | sort | uniq -dc
2009-03-21 18:15:14
User: Vadi
Functions: cat sort uniq
Tags: sort awk uniq duplicate occur
1
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Display duplicated lines in a file

Displays the duplicated lines in a file and their occuring frequency.

Comments (3) | 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
20
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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
cat count.txt | awk '{ sum+=$1} END {print sum}'
2009-03-16 00:22:13
User: duxklr
Functions: awk cat
Tags: awk
7
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Using awk to sum/count a column of numbers.

Takes a input file (count.txt) that looks like:

1

2

3

4

5

It will add/sum the first column of numbers.

Comments (7) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
zgrep "Failed password" /var/log/auth.log* | awk '{print $9}' | sort | uniq -c | sort -nr | less
2009-03-03 13:45:56
User: dbart
Functions: awk sort uniq zgrep
Tags: ssh sort zgrep awk uniq
7
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Check for login failures and summarize

This command checks for the number of times when someone has tried to login to your server and failed. If there are a lot, then that user is being targeted on your system and you might want to make sure that user either has remote logins disabled, or has a strong password, or both. If your output has an "invalid" line, it is a summary of all logins from users that don't exist on your system.

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netstat -alpn | grep :80 | awk '{print $4}' |awk -F: '{print $(NF-1)}' |sort | uniq -c | sort -n
2009-02-19 04:59:32
User: nitins
Functions: awk grep netstat sort uniq
Tags: sort awk uniq netstat ddos
-2
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Checking total connections to each Ip inserver

Useful to check DDoS attacks on servers.

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