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Commands using awk from sorted by
Terminal - Commands using awk - 1,188 results
tail -f /var/log/apache2/access.log | awk -W interactive '!x[$1]++ {print $1}'
2010-01-12 15:23:03
User: pykler
Functions: awk tail
1

Prints the unique IP Addresses as they arrive from an Apache `access.log` file.

The '-W interactive' tells awk to start writing to stdout immediately and not buffer the output.

This command builds on the uniq lines without sorting command (http://www.commandlinefu.com/commands/view/4389/remove-duplicate-entries-in-a-file-without-sorting.)

grep -e `date +%Y-%m-%d` /var/log/dpkg.log | awk '/install / {print $4}' | uniq | xargs apt-get -y remove
ps -ef | grep user | awk '{print $2}' | while read pid; do echo $pid ; pfiles $pid| grep portnum; done
2010-01-11 12:34:51
User: sharfah
Functions: awk echo grep ps read
0

My old Solaris server does not have lsof, so I have to use pfiles.

awk 'NR%3==1' file
2010-01-08 18:52:24
Functions: awk
4

A better way to show the file lines 3n + 1

awk '{print NR,$0}'
awk '{if (NR % 3 == 1) print $0}' foo > foo_every3_position1; awk '{if (NR % 3 == 2) print $0}' foo > foo_every3_position2; awk '{if (NR % 3 == 0) print $0}' foo > foo_every3_position3
2010-01-08 04:20:06
User: oshazard
Functions: awk
-1

awk extract every nth line.

Generic is:

awk '{if (NR % LINE == POSITION) print $0}' foo

where "last" position is always 0 (zero).

awk 'BEGIN{while (a++<50) s=s "-"; print s}'
2010-01-06 16:16:35
User: SuperFly
Functions: awk
0

Change the number 50 to whatever number of characters you want. Change the character inside the double quotes to whatever you want printed.

for x in `ptree | awk '{print $1}'`; do pfiles $x | grep ${PORT} > /dev/null 2>&1; if [ x"$?" == "x0" ]; then ps -ef | grep $x | grep -v grep; fi; done 2> /dev/null
2010-01-05 17:02:23
User: bpfx
Functions: awk grep ps
0

Can use lsof, but since it's not part of the base OS, it's not always available.

pfiles -F /proc/* 2>/dev/null | awk '/^[0-9]+/{proc=$1};/[s]ockname: AF_INET/{print proc $0}'
2010-01-04 21:21:32
User: hunternet
Functions: awk
1

Command line to get which PID is opening a socket on IP and PORT.

Only useful under Solaris.

(bzcat BZIP2_FILES && cat TEXT_FILES) | grep -E "Invalid user|PAM" | grep -o -E "from .+" | awk '{print $2}' | sort | uniq >> /etc/hosts.deny
2010-01-03 04:41:51
User: jayhawkbabe
Functions: awk cat grep sort uniq
3

Searches all log files (including archived bzip2 files) for invalid user and PAM authentication errors, both of which are indicative of brute force attempts at logging into computer. A list of all unique IP addresses and domain names is appended to hosts.deny. The command (and grep error messages) will work on Mac OS X 10.6, small adjustments may be needed for other OSs.

BACKUP_FILE_SIZE=`eval ls -l ${BACKUP_FILE} | awk {'print $5'}`; if [ $BACKUP_FILE_SIZE -le 20 ]; then echo "its empty"; else echo "its not empty"; fi
2009-12-29 08:34:37
User: Redrocket
Functions: awk echo ls
-2

If you gzip an empty file it becomes 20 bytes. Some backup checks i do check to see if the file is greater than zero size (-s flag) but this is no good here. Im sure someone has a better check than me for this? No check to see if file exists before checking it's size.

calc() { awk 'BEGIN { OFMT="%f"; print '"$*"'; exit}'; }
$class=ExampleClass; $path=src; for constant in `grep ' const ' $class.php | awk '{print $2;}'`; do grep -r "$class::$constant" $path; done
DIR=. ; FSTYPE=$(df -TP ${DIR} | grep -v Type | awk '{ print $2 }') ; echo "${FSTYPE}"
2009-12-22 14:01:50
User: unixhome
Functions: awk df echo grep
1

Exclude 400 client hosts with NFS auto-mounted home directories.

Easily modified for inclusion in your scripts.

curl -s search.twitter.com | awk -F'</?[^>]+>' '/\/intra\/trend\//{print $2}'
curl --silent search.twitter.com | sed -n '/div id=\"hot\"/,/div/p' | awk -F\> '{print $2}' | awk -F\< '{print $1}' | sed '/^$/d'
ps -ylC httpd --sort:rss | awk '{ SUM += $8 } END { print SUM/1024 }'
2009-12-20 15:41:50
User: nasser
Functions: awk ps
0

This command will show you amount of memory used by apache

awk '!x[$0]++' <file>
2009-12-20 02:33:21
User: din7
Functions: awk
67

Using awk, find duplicates in a file without sorting, which reorders the contents. awk will not reorder them, and still find and remove duplicates which you can then redirect into another file.

awk '/.*{$/{s[$1]=z[$1]=j+0}{l[j++]=$0}END{asorti(s);for(v in s){while(l[z[s[v]]]!~/}$/)print l[z[s[v]]++];print"}"ORS}}'
tar -cf - . | pv -s $(du -sb . | awk '{print $1}') | gzip > out.tgz
2009-12-18 17:09:08
User: opertinicy
Functions: awk du gzip tar
26

What happens here is we tell tar to create "-c" an archive of all files in current dir "." (recursively) and output the data to stdout "-f -". Next we specify the size "-s" to pv of all files in current dir. The "du -sb . | awk ?{print $1}?" returns number of bytes in current dir, and it gets fed as "-s" parameter to pv. Next we gzip the whole content and output the result to out.tgz file. This way "pv" knows how much data is still left to be processed and shows us that it will take yet another 4 mins 49 secs to finish.

Credit: Peteris Krumins http://www.catonmat.net/blog/unix-utilities-pipe-viewer/

awk -F":" '{ print $1 }' /etc/passwd | while read UU ; do STATUS=$(passwd -S ${UU} | grep locked 2>/dev/null) ; if [[ ! -z ${STATUS} ]] ; then echo "Account ${UU} is locked." ; fi ; done
echo $LS_COLORS | sed 's/:/\n/g' | awk -F= '!/^$/{printf("%s \x1b[%smdemo\x1b[0m\n",$0,$2)}'
2009-12-15 01:17:46
User: bones7456
Functions: awk echo sed
8

This can show all ls colors, with a demo.

zcat access_log.*.gz | awk '{print $7}' | sort | uniq -c | sort -n | tail -n 20
curl -sL 'dynamic.xkcd.com/comic/random/' | awk -F\" '/^<img/{printf("<?xml version=\"1.0\"?>\n<xkcd>\n<item>\n <title>%s</title>\n <comment>%s</comment>\n <image>%s</image>\n</item>\n</xkcd>\n", $6, $4, $2)}'
wget -q http://dynamic.xkcd.com/comic/random/ -O-| sed -n '/<img src="http:\/\/imgs.xkcd.com\/comics/{s/.*\(http:.*\)" t.*/\1/;p}' | awk '{system ("wget -q " $1 " -O- | display -title $(basename " $1") -write /tmp/$(basename " $1")");}'
2009-12-09 13:41:25
User: laugg
Functions: awk sed wget
Tags: sed awk wget comic
0

Only need to install Image Magick package.

Display a xkcd comic with its title and save it in /tmp directory

If you prefer to view the newest xkcd, use this command:

wget -q http://xkcd.com/ -O-| sed -n '/<img src="http:\/\/imgs.xkcd.com\/comics/{s/.*\(http:.*\)" t.*/\1/;p}' | awk '{system ("wget -q " $1 " -O- | display -title $(basename " $1") -write /tmp/$(basename " $1")");}'