Commands tagged awk (348)

  • This oneliner uses Imagemagic's identify utility to show the exif GPS information of an image an also converts Grad/MIn/Sec representation to a decimal degree number Show Sample Output


    5
    identify -verbose my_image.jpg | awk 'function cf(i){split(i,a,"/");if(length(a)==2){return a[1]/a[2]}else{return a[1]}}/GPS/{if($1~/GPSLatitude:|GPSLongitude:/){s=$0;gsub(/,/,"",$0);printf("%s (%f)\n", s, $2+cf($3)/60+cf($4)/3600)}else{print}}'
    ichbins · 2022-02-20 10:17:49 322
  • Outputs utf-8 smileys Show Sample Output


    5
    printf "$(awk 'BEGIN{c=127;while(c++<191){printf("\xf0\x9f\x98\\%s",sprintf("%o",c));}}')"
    ichbins · 2022-04-06 12:10:37 437
  • "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


    4
    seq 100 | awk '{sum+=$1} END {print sum}'
    kaan · 2009-03-24 20:30:40 5
  • This appends a random number as a first filed of all lines in SOMEFILE then sorts by the first column and finally cuts of the random numbers.


    4
    awk 'BEGIN{srand()}{print rand(),$0}' SOMEFILE | sort -n | cut -d ' ' -f2-
    axelabs · 2009-05-29 01:20:50 11
  • just change the date following the -r flag, and/or the user name in the user== conditional statement, and substitute yms_web with the name of your module


    4
    svn log -v -r{2009-05-21}:HEAD | awk '/^r[0-9]+ / {user=$3} /yms_web/ {if (user=="george") {print $2}}' | sort | uniq
    jemptymethod · 2009-06-05 14:07:28 11
  • This will calculate a running standard deviation in one pass and should never have the possibility for overflow that can happen with other implementations. I suppose there is a potential for underflow in the corner case where the deltas are small or the values themselves are small.


    4
    awk '{delta = $1 - avg; avg += delta / NR; mean2 += delta * ($1 - avg); } END { print sqrt(mean2 / NR); }'
    ashawley · 2009-09-11 04:46:01 5

  • 4
    svn ci `svn stat |awk '/^A/{printf $2" "}'`
    realist · 2009-11-04 03:30:07 3

  • 4
    renice +5 -p $(pidof <process name>)
    0x2142 · 2010-01-19 22:16:24 3
  • (Apparently it is too long so I put it in sample output, I hope that is OK.) Run the long command (or put it in your .bashrc) in sample output then run: fbemailscraper YourFBEmail Password Voila! Your contacts' emails will appear. Facebook seems to have gotten rid of the picture encoding of emails and replaced it with a text based version making it easy to scrape! Needs curl to run and it was made pretty quickly so there might be bugs. Show Sample Output


    4
    fbemailscraper YourFBEmail Password
    dabom · 2010-01-31 00:44:35 45
  • Ever gone to a site that has an MP3 embedded into a pesky flash player, but no download link? Well, this one-liner will yank the names of those tunes straight out of FF's cache in a nice, easy to read list. What you do with them after that is *ahem* no concern of mine. ;) Show Sample Output


    4
    for i in `ls ~/.mozilla/firefox/*/Cache`; do file $i | grep -i mpeg | awk '{print $1}' | sed s/.$//; done
    BoxingOctopus · 2010-04-11 23:14:18 7
  • Case Insensitive! and Works even if the "<title>...</title>" spans over multiple line. Simple! :-) Show Sample Output


    4
    awk 'BEGIN{IGNORECASE=1;FS="<title>|</title>";RS=EOF} {print $2}' file.html
    sata · 2010-04-20 10:54:03 5
  • Searches for web radio by submitted keyword and returns the station name and the link for listing . May be enhanced to read user's selection and submit it to mplayer. Show Sample Output


    4
    echo "Keyword?";read keyword;query="http://www.shoutcast.com/sbin/newxml.phtml?search="$keyword"";curl -s $query |awk -F '"' 'NR <= 4 {next}NR>15{exit}{sub(/SHOUTcast.com/,"http://yp.shoutcast.com/sbin/tunein-station.pls?id="$6)}{print i++" )"$2}'
    benyounes · 2010-05-03 00:44:10 8

  • 4
    tail -n2000 /var/www/domains/*/*/logs/access_log | awk '{print $1}' | sort | uniq -c | sort -n | awk '{ if ($1 > 20)print $1,$2}'
    allrightname · 2010-05-10 19:08:37 3
  • This one is a bit more robust -- the remote machine may not have an .ssh directory, and it may not have an authorized_keys file, but if it does already, and you want to replace your ssh public key for some reason, this will work in that case as well, without duplicating the entry.


    4
    cat ~/.ssh/id_rsa.pub | ssh <REMOTE> "(cat > tmp.pubkey ; mkdir -p .ssh ; touch .ssh/authorized_keys ; sed -i.bak -e '/$(awk '{print $NF}' ~/.ssh/id_rsa.pub)/d' .ssh/authorized_keys; cat tmp.pubkey >> .ssh/authorized_keys; rm tmp.pubkey)"
    tamouse · 2011-09-30 07:39:24 18
  • Read all lines using decimal marker as point, then add all them up and outputs the result. Show Sample Output


    4
    awk '{a+=$0}END{print a}' file
    bugmenot · 2022-08-15 23:04:31 476
  • 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


    3
    seq 6 | awk '{for(x=1; x<=5; x++) {printf ("%f ", rand())}; printf ("\n")}'
    kaan · 2009-03-24 21:33:38 5
  • Sometimes jittery data hides trends, performing a rolling average can give a clearer view.


    3
    awk 'BEGIN{size=5} {mod=NR%size; if(NR<=size){count++}else{sum-=array[mod]};sum+=$1;array[mod]=$1;print sum/count}' file.dat
    mungewell · 2009-05-29 00:07:24 4
  • The grep switches eliminate the need for awk and sed. Modifying vim with -p will show all files in separate tabs, -o in separate vim windows. Just wish it didn't hose my terminal once I exit vim!!


    3
    grep -Hrli 'foo' * | xargs vim
    dere22 · 2009-09-03 15:44:05 12
  • This pipeline will find, sort and display all files based on mtime. This could be done with find | xargs, but the find | xargs pipeline will not produce correct results if the results of find are greater than xargs command line buffer. If the xargs buffer fills, xargs processes the find results in more than one batch which is not compatible with sorting. Note the "-print0" on find and "-0" switch for perl. This is the equivalent of using xargs. Don't you love perl? Note that this pipeline can be easily modified to any data produced by perl's stat operator. eg, you could sort on size, hard links, creation time, etc. Look at stat and just change the '9' to what you want. Changing the '9' to a '7' for example will sort by file size. A '3' sorts by number of links.... Use head and tail at the end of the pipeline to get oldest files or most recent. Use awk or perl -wnla for further processing. Since there is a tab between the two fields, it is very easy to process. Show Sample Output


    3
    find $HOME -type f -print0 | perl -0 -wn -e '@f=<>; foreach $file (@f){ (@el)=(stat($file)); push @el, $file; push @files,[ @el ];} @o=sort{$a->[9]<=>$b->[9]} @files; for $i (0..$#o){print scalar localtime($o[$i][9]), "\t$o[$i][-1]\n";}'|tail
    drewk · 2009-09-21 22:11:16 11
  • You set the file/dirname transfer variable, in the end point you set the path destination, this command uses pipe view to show progress, compress the file outut and takes account to change the ssh cipher. Support dirnames with spaces. Merged ideas and comments by http://www.commandlinefu.com/commands/view/4379/copy-working-directory-and-compress-it-on-the-fly-while-showing-progress and http://www.commandlinefu.com/commands/view/3177/move-a-lot-of-files-over-ssh Show Sample Output


    3
    file='path to file'; tar -cf - "$file" | pv -s $(du -sb "$file" | awk '{print $1}') | gzip -c | ssh -c blowfish user@host tar -zxf - -C /opt/games
    starchox · 2010-01-19 16:02:45 37
  • Alternatively: export MyVAR=84; awk '{ print ENVIRON["MyVAR"] }'


    3
    MyVAR=85 awk '{ print ENVIRON["MyVAR"] }'
    depesz · 2011-04-14 16:46:23 3
  • rename file name with fixed length nomeric format pattern Show Sample Output


    3
    ls *.jpg | awk -F'.' '{ printf "%s %04d.%s\n", $0, $1, $2; }' | xargs -n2 mv
    hute37 · 2011-05-01 13:32:58 6
  • Just an alternative with more advanced formating for readability purpose. It now uses colors (too much for me but it's a kind of proof-of-concept), and adjust columns. Show Sample Output


    3
    curl -u username --silent "https://mail.google.com/mail/feed/atom" | awk 'BEGIN{FS="\n";RS="(</entry>\n)?<entry>"}NR!=1{print "\033[1;31m"$9"\033[0;32m ("$10")\033[0m:\t\033[1;33m"$2"\033[0m"}' | sed -e 's,<[^>]*>,,g' | column -t -s $'\t'
    frntn · 2011-10-15 23:15:52 3
  • This is mostly for my own notes but this command will compute a md5 message digest from the command line. You can also replace md5sum with other checksum commands (e.g., sha1sum) Show Sample Output


    3
    echo -n "password"|md5sum|awk '{print $1}'
    windfold · 2011-11-08 21:34:50 5
  • Like the original version except it does not include the parent apache process or the grep process and adds "sudo" so it can be run by user.


    3
    ps h --ppid $(cat /var/run/apache2.pid) | awk '{print"-p " $1}' | xargs sudo strace
    colinmollenhour · 2012-03-21 01:59:41 3
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preserve disk; keep OS clean
if you use disk-based swap then it can defeat the purpose of this function.

using tee to echo to a system file with sudo privileges
We sometimes need to change kernel parameters by echoing the file . This needs root privilege and if we do it using sudo like this , it fails $ sudo echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor -bash: /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor: Permission denied We can achieve this with the tee command by just doing sudo without logging as root user http://www.zaman4linux.in/2010/09/using-tee-to-echo-to-system-file-with.html

list block devices
Shows all block devices in a tree with descruptions of what they are.

Uniquely (sort of) color text so you can see changes
Colorify colors input by converting the text to a number and then performing modulo 7 on it. This resulting number is used as the color escape code. This can be used to color the results of commands with complex outputs (like "482279054165371") so if any of the digits change, there's a good chance the color will change too. I say good chance because there's only 7 unique colors here, so assuming you were watching random numbers, there would be a 6/7 chance that the color would change when the number changed. This should really only be used to help quickly identify when things change, but should not be the only thing relied upon to positively assert that an output has not changed.

Backup a file with a date-time stamp
1. you don't need to prepend the year with 20 - just use Y instead of y 2. you may want to make your function a bit more secure: buf () { cp ${1?filename not specified}{,$(date +%Y%m%d_%H%M%S)}; }

Boot another OS at next startup

Bash prompt with user name, host, history number, current dir and just a touch of color
I put that line in my .bash_profile (OS X) and .bashrc (Linux). Here is a summary of what the \char means: n=new line, u=user name, h=host, !=history number, w=current work directory The \[\e[32m\] sequence set the text to bright green and \[\e[0m\] returns to normal color. For more information on what you can set in your bash prompt, google 'bash prompt'

Generate SHA1 hash for each file in a list
All output is placed in file SHA1SUMS which you can later check with 'sha1sum --check'. Works on most Linux distros where 'sha1sum' is installed.

Backup a local drive into a file on the remote host via ssh

Instantly load bash history of one shell into another running shell
By default bash history of a shell is appended (appended on Ubuntu by default: Look for 'shopt -s histappend' in ~/.bashrc) to history file only after that shell exits. Although after having written to the history file, other running shells do *not* inherit that history - only newly launched shells do. This pair of commands alleviate that.


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