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May 19, 2015 - A Look At The New Commandlinefu
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Commands using awk from sorted by
Terminal - Commands using awk - 1,210 results
ls -l --time-style=+%Y-%m-%d | awk "/$(date +'%Y-%m-%d')/ {print \$7}"
2010-07-29 05:30:29
Functions: awk ls
1

This version eliminates the grep before the awk, which is always good. It works for GNU core utils and ensures that the date output of ls matches the format in the pattern match, regardless of locale, etc.

On BSD-based systems, you can easily eliminate both the grep and the awk:

find . -maxdepth 1 -Btime -$(date +%kh%lm) -type f

TODAY=`date +"%b %d"`;ls -l | grep "$TODAY" | awk '{print $9}'
netstat -l -p --tcp | egrep -e 'www.*[0-9]{3,4}\/(apache2|httpd)' | awk '{print$7}'
lsof /dev/snd/pcm*p /dev/dsp | awk ' { print $2 }' | xargs kill
2010-07-23 20:24:16
User: alustenberg
Functions: awk xargs
2

for when a program is hogging the sound output. finds, and kills. add -9 to the end for wedged processes. add in 'grep ^program' after lsof to filter.

awk '$1~/^DocumentRoot/{print $2}' /etc/apache2/sites-available/default
git log --format='%aN <%aE>' | awk '{arr[$0]++} END{for (i in arr){print arr[i], i;}}' | sort -rn | cut -d\ -f2-
2010-07-19 11:40:52
Functions: awk cut sort
Tags: git
4

Gets the authors, sorts by number of commits (as a vague way of estimating how much of the project is their work, i.e. the higher in the list, the more they've done) and then outputs the results.

for i in {a..z} ; do man -k $i |grep -i "^$i" |wc | awk 'BEGIN { OFS = ":"; ORS = "" }{print $1, "\t"}' && echo $i ;done
awk '{print $1}' < three-column.txt > first-column.txt
netstat -an | grep ESTABLISHED | awk '\''{print $5}'\'' | awk -F: '\''{print $1}'\'' | sort | uniq -c | awk '\''{ printf("%s\t%s\t",$2,$1); for (i = 0; i < $1; i++) {printf("*")}; print ""}'\''
2010-07-09 00:25:45
User: mramos
Functions: awk grep netstat sort uniq
7

Displays a connection histogram of active tcp connections. Works even better under an alias. Thanks @Areis1 for sharing this one.

awk 'NR==4'
awk 'NR==linenumber' filename
cat WAR_AND_PEACE_By_LeoTolstoi.txt | tr -cs "[:alnum:]" "\n"| tr "[:lower:]" "[:upper:]" | awk '{h[$1]++}END{for (i in h){print h[i]" "i}}'|sort -nr | cat -n | head -n 30
2010-07-05 06:39:20
User: cp
Functions: awk cat head sort tr
11

using

cat WAR_AND_PEACE_By_LeoTolstoi.txt | tr -cs "[:alnum:]" "\n"| tr "[:lower:]" "[:upper:]" | sort -S16M | uniq -c |sort -nr | cat -n | head -n 30

("sort -S1G" - Linux/GNU sort only) will also do the job but as some drawbacks (caused by space/time complexity of sorting) for bigger files...

ifconfig | awk '/^eth0/ {print $5}'
curl -s "http://www.socrata.com/api/views/vedg-c5sb/rows.json?search=Axelrod" | grep "data\" :" | awk '{ print $17 }'
2010-07-01 23:54:54
User: mheadd
Functions: awk grep
Tags: awk grep curl
2

Query the Socrata Open Data API being used by the White House to find any employee's salary using curl, grep and awk.

Change the value of the search parameter (example uses Axelrod) to the name of any White House staffer to see their annual salary.

for i in `grep -n "SomeRegEx" foo.txt | sed 's/:/ /' | awk '{print $1}'`; do echo "head -n `echo "$i+4" | bc` foo.txt | tail -n 5"; done > headsandtails.sh
2010-07-01 05:48:02
User: reklis
Functions: awk echo sed
-2

Finds the line number matching the regex, then passes that to BC for some math, passes that to head, and uses tail to trim off the unwanted section at the top. The whole thing is spit out to a script that can then be shared or run. Comes in handy for reading select sections from error logs.

grep '^MemFree:' /proc/meminfo | awk '{ mem=($2)/(1024) ; printf "%0.0f MB\n", mem }'
2010-06-30 18:33:29
User: dbbolton
Functions: awk grep printf
4

This will show the amount of physical RAM that is left unused by the system.

ps auxwww | grep outofcontrolprocess | awk '{print $2}' | xargs kill -9
ip addr show eth0 | awk '/inet / {FS = "/"; $0 = $2; print $1}'
2010-06-30 14:33:48
User: kniht
Functions: awk
2

Combines wgzhao's grep | awk | sed into one awk command.

ifconfig eth0 | awk '/inet / {print $2}' | cut -d ':' -f2
wget -O - http://www.commandlinefu.com/commands/browse/rss 2>/dev/null | awk '/\s*<title/ {z=match($0, /CDATA\[([^\]]*)\]/, b);print b[1]} /\s*<description/ {c=match($0, /code>(.*)<\/code>/, d);print d[1]} ' | grep -v "^$"
2010-06-29 16:22:03
User: nikunj
Functions: awk grep wget
Tags: awk grep meta
2

A Quick variation to the latest commands list with the new-lines skipped. This is faster to read.

ifconfig eth0 | grep "inet " | cut -d ':' -f2 | awk '{print $1}'
2010-06-29 00:06:08
User: jaimerosario
Functions: awk cut grep ifconfig
5

I've been using it in a script to build from scratch proxy servers.

free -m | awk '/buffer/ {print $4}'
2010-06-27 23:30:27
User: DaveQB
Functions: awk free
Tags: ram free
3

Here we instead show a more real figure for how much free RAM you have when taking into consideration buffers that can be freed if needed.

Unix machines leave data in memory but marked it free to overwrite, so using the first line from the "free" command will mostly give you back a reading showing you are almost out of memory, but in fact you are not, as the system can free up memory as soon as it is needed.

I just noticed the free command is not on my OpenBSD box.

free -m | awk '/Mem/ {print $4}'
awk 'BEGIN { ARGV[ARGC++]=ARGV[ARGC-1] } NR!=FNR { if(num==0) num=NR-1; if(FNR<num) {print} else { ORS=""; print } } ' abc1.txt > abc2.txt
ip addr show eth0 |grep 'inet\b' |awk '{print $2}' |sed -r -e 's/\/.*?//g'