Commands tagged awk (348)

  • Shows picture exif GPS info if any and converts coords to a decimal degree number

    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
  • Have a smile

    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 12:10:37 438
  • 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


    4
    seq 100 | awk '{sum+=$1} END {print sum}'
    kaan · 2009-03-24 20:30:40 5
  • Randomize lines in a file

    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
  • gets all files committed to svn by a particular user since a particular date

    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
  • Display the standard deviation of a column of numbers with awk

    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
  • Commit only newly added files to subversion repository


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


    4
    renice +5 -p $(pidof <process name>)
    0x2142 · 2010-01-19 22:16:24 3
  • Facebook Email Scraper

    (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
  • Grab a list of MP3s out of Firefox's cache

    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
  • Extract title from HTML files

    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
  • Search shoutcast web radio by keyword

    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
  • Count number of hits per IP address in last 2000 lines of apache logs and print the IP and hits if hits > 20


    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
  • Copy your ssh public key to a server from a machine that doesn't have ssh-copy-id

    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
  • How to sum lines with decimals in awk

    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
  • 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


    3
    seq 6 | awk '{for(x=1; x<=5; x++) {printf ("%f ", rand())}; printf ("\n")}'
    kaan · 2009-03-24 21:33:38 5
  • Awk: Perform a rolling average on a column of data

    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
  • Edit all files found having a specific string found by grep

    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
  • Find and display most recent files using find and perl

    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
  • improve copy file over ssh showing progress

    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
  • BASH: Print shell variable into AWK

    Alternatively: export MyVAR=84; awk '{ print ENVIRON["MyVAR"] }'


    3
    MyVAR=85 awk '{ print ENVIRON["MyVAR"] }'
    depesz · 2011-04-14 16:46:23 3
  • Numeric zero padding file rename

    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
  • Check your unread Gmail from the command line

    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
  • Generate Sha1, MD5 hash using echo

    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
  • easily strace all your apache *child* processes

    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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Lists unambigously names of all xml elements used in files in current directory
This set of commands was very convenient for me when I was preparing some xml files for typesetting a book. I wanted to check what styles I had to prepare but coudn't remember all tags that I used. This one saved me from error-prone browsing of all my files. It should be also useful if one tries to process xml files with xsl, when using own xml application.

Find files that have been modified on your system in the past 60 minutes
Useful mainly for debugging or troubleshooting an application or system, such as X11, Apache, Bind, DHCP and others. Another useful switch that can be combined with -mmin, -mtime and so forth is -daystart. For example, to find files that were modified in the /etc directory only yesterday: $ sudo find /etc -daystart -mtime 1 -type f

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

recursively change file name from uppercase to lowercase (or viceversa)
easier way to recursively change files to lowercase using rename instead

how many pages will my text files print on?
This gives a very rough estimate of how many pages your text files will print on. Assumes 60 lines per page, and does not take long lines into account.

Find and display most recent files using find and perl
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.

list files recursively by size

check open ports without netstat or lsof

Scans for open ports using telnet

Efficient count files in directory (no recursion)
$ time perl -e 'if(opendir D,"."){@a=readdir D;print $#a - 1,"\n"}' 205413 real 0m0.497s user 0m0.220s sys 0m0.268s $ time { ls |wc -l; } 205413 real 0m3.776s user 0m3.340s sys 0m0.424s ********* ** EDIT: turns out this perl liner is mostly masturbation. this is slightly faster: $ find . -maxdepth 1 | wc -l sh-3.2$ time { find . -maxdepth 1|wc -l; } 205414 real 0m0.456s user 0m0.116s sys 0m0.328s ** EDIT: now a slightly faster perl version $ perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' sh-3.2$ time perl -e 'if(opendir D,"."){++$c foreach readdir D}print $c-1,"\n"' 205414 real 0m0.415s user 0m0.176s sys 0m0.232s

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