Commands tagged awk (348)

  • Upload images to omploader.org from the command line.

    This function uploads images to http://omploader.org and then prints out the links to the file. Some coloring can also be added to the command with: ompload() { curl -F file1=@"$1" http://omploader.org/upload|awk '/Info:|File:|Thumbnail:|BBCode:/{gsub(/<[^<]*?\/?>/,"");$1=$1;sub(/^/,"\033[0;34m");sub(/:/,"\033[0m:");print}';} Show Sample Output


    8
    ompload() { curl -# -F file1=@"$1" http://ompldr.org/upload|awk '/Info:|File:|Thumbnail:|BBCode:/{gsub(/<[^<]*?\/?>/,"");$1=$1;print}';}
    eightmillion · 2009-11-07 20:56:52 5
  • Remove all unused kernels with apt-get

    This should do the same thing and is about 70 chars shorter. Show Sample Output


    8
    aptitude remove $(dpkg -l|egrep '^ii linux-(im|he)'|awk '{print $2}'|grep -v `uname -r`)
    dbbolton · 2010-06-10 21:23:00 10
  • Find default gateway


    8
    ip route | awk '/default/{print $3}'
    rthemocap · 2010-08-10 21:16:40 51
  • Find the cover image for an album

    This bash function uses albumart.org to find the cover for an album. It returns an amazon.com url to the image. Usage: albumart [artist] [album] These arguments can be reversed and if the album name is distinct enough, it may be possible to omit the artist. The command can be extended with wget to automatically download the matching image like this: albumart(){ local x y="$@";x=$(awk '/View larger image/{gsub(/^.*largeImagePopup\(.|., .*$/,"");print;exit}' <(curl -s 'http://www.albumart.org/index.php?srchkey='${y// /+}'&itempage=1&newsearch=1&searchindex=Music'));[ -z "$x" ]&&echo "Not found."||wget "$x" -O "${y}.${x##*.}";} Show Sample Output


    7
    albumart(){ local y="$@";awk '/View larger image/{gsub(/^.*largeImagePopup\(.|., .*$/,"");print;exit}' <(curl -s 'http://www.albumart.org/index.php?srchkey='${y// /+}'&itempage=1&newsearch=1&searchindex=Music');}
    eightmillion · 2009-11-15 19:54:16 11
  • Print trending topics on Twitter


    7
    curl -s search.twitter.com | awk -F'</?[^>]+>' '/\/intra\/trend\//{print $2}'
    putnamhill · 2009-12-22 01:01:02 12
  • Remove all unused kernels with apt-get

    Note the double space: "...^ii␣␣linux-image-2..." Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel). I'm bummed that this took 228 characters. I'd like to see a simpler version. Show Sample Output


    7
    aptitude remove $(dpkg -l|awk '/^ii linux-image-2/{print $2}'|sed 's/linux-image-//'|awk -v v=`uname -r` 'v>$0'|sed 's/-generic//'|awk '{printf("linux-headers-%s\nlinux-headers-%s-generic\nlinux-image-%s-generic\n",$0,$0,$0)}')
    __ · 2010-12-11 11:38:15 7
  • easily strace all your apache processes

    This one-liner will use strace to attach to all of the currently running apache processes output and piped from the initial "ps auxw" command into some awk. Show Sample Output


    7
    ps auxw | grep sbin/apache | awk '{print"-p " $2}' | xargs strace
    px · 2011-03-14 21:45:22 34
  • Print one . instead of each line

    If you're running a command with a lot of output, this serves as a simple progress indicator. This avoids the need to use `/dev/null` for silencing. It works for any command that outputs lines, updates live (`fflush` avoids buffering), and is simple to understand. Show Sample Output


    7
    alias ...="awk '{fflush(); printf \".\"}' && echo \"\""
    lgarron · 2014-02-22 22:20:22 15
  • Check how far along (in %) your program is in a file

    Imagine you've started a long-running process that involves piping data, but you forgot to add the progress-bar option to a command. e.g. xz -dc bigdata.xz | complicated-processing-program > summary . This command uses lsof to see how much data xz has read from the file. lsof -o0 -o -Fo FILENAME Display offsets (-o), in decimal (-o0), in parseable form (-Fo) This will output something like: . p12607 f3 o0t45187072 . Process id (p), File Descriptor (f), Offset (o) . We stat the file to get its size stat -c %s FILENAME . Then we plug the values into awk. Split the line at the letter t: -Ft Define a variable for the file's size: -s=$(stat...) Only work on the offset line: /^o/ . Note this command was tested using the Linux version of lsof. Because it uses lsof's batch option (-F) it may be portable. . Thanks to @unhammer for the brilliant idea. Show Sample Output


    7
    F=bigdata.xz; lsof -o0 -o -Fo $F | awk -Ft -v s=$(stat -c %s $F) '/^o/{printf("%d%%\n", 100*$2/s)}'
    flatcap · 2015-09-19 22:22:43 18
  • Generates a TV noise alike output in the terminal

    Generates a TV noise alike output in the terminal. Can be combined with https://www.commandlinefu.com/commands/view/9728/make-some-powerful-pink-noise


    7
    while true;do printf "$(awk -v c="$(tput cols)" -v s="$RANDOM" 'BEGIN{srand(s);while(--c>=0){printf("\xe2\x96\\%s",sprintf("%o",150+int(10*rand())));}}')";done
    ichbins · 2020-05-08 09:55:36 209
  • Display the standard deviation of a column of numbers with awk


    6
    awk '{sum+=$1; sumsq+=$1*$1} END {print sqrt(sumsq/NR - (sum/NR)**2)}' file.dat
    kaan · 2009-03-24 21:56:40 9
  • Check which files are opened by Firefox then sort by largest size.

    Check which files are opened by Firefox then sort by largest size (in MB). You can see all files opened by just replacing grep to "/". Useful if you'd like to debug and check which extensions or files are taking too much memory resources in Firefox. Show Sample Output


    6
    FFPID=$(pidof firefox-bin) && lsof -p $FFPID | awk '{ if($7>0) print ($7/1024/1024)" MB -- "$9; }' | grep ".mozilla" | sort -rn
    josue · 2009-08-16 08:58:22 7
  • Visualizing system performance data


    6
    (echo "set terminal png;plot '-' u 1:2 t 'cpu' w linespoints;"; sudo vmstat 2 10 | awk 'NR > 2 {print NR, $13}') | gnuplot > plot.png
    grokskookum · 2009-09-23 16:40:13 12
  • Capture video of a linux desktop


    6
    ffmpeg -f x11grab -s `xdpyinfo | grep 'dimensions:'|awk '{print $2}'` -r 25 -i :0.0 -sameq /tmp/out.mpg > /root/howto/capture_screen_video_ffmpeg
    brubaker · 2010-03-27 21:31:34 5
  • drop first column of output by piping to this


    6
    tr -s ' ' | cut -d' ' -f2-
    sesom42 · 2015-05-08 12:47:09 10
  • Replace Solaris vmstat numbers with human readable format

    % cat ph-vmstat.awk # Return human readable numbers function hrnum(a) { b = a ; if (a > 1000000) { b = sprintf("%2.2fM", a/1000000) ; } else if (a > 1000) { b = sprintf("%2.2fK", a/1000) ; } return(b) ; } # Return human readable storage function hrstorage(a) { b = a ; if (a > 1024000) { b = sprintf("%2.2fG", a/1024/1024) ; } else if (a > 1024) { b = sprintf("%2.2fM", a/1024) ; } return(b) ; } OFS=" " ; $1 !~ /[0-9].*/ {print} $1 ~ /[0-9].*/ { $4 = hrstorage($4) ; $5 = hrstorage($5) ; $9 = hrnum($9) ; $10 = hrnum($10) ; $17 = hrnum($17) ; $18 = hrnum($18) ; $19 = hrnum($19) ; print ; } Show Sample Output


    5
    vmstat 1 10 | /usr/xpg4/bin/awk -f ph-vmstat.awk
    MarcoN · 2009-05-04 04:55:00 4
  • Get line number of all matches in a file


    5
    awk '/match/{print NR}' file
    inof · 2009-06-03 17:34:13 7
  • Capture screen and mic input using FFmpeg and ALSA

    Yet another x11grab using ffmpeg. I also added mic input to the capturing video stream using alsa. Yet I need to find out how to capture audio which is currently playing. Show Sample Output


    5
    ffmpeg -f alsa -itsoffset 00:00:02.000 -ac 2 -i hw:0,0 -f x11grab -s $(xwininfo -root | grep 'geometry' | awk '{print $2;}') -r 10 -i :0.0 -sameq -f mp4 -s wvga -y intro.mp4
    mohan43u · 2010-03-31 09:33:05 6
  • Show interface/ip using awk

    Interfaces like lo can be omitted from the beginning, there are probably better ways of doing this, i'm a noob at awk. Show Sample Output


    5
    ifconfig -a| awk '/^wlan|^eth|^lo/ {;a=$1;FS=":"; nextline=NR+1; next}{ if (NR==nextline) { split($2,b," ")}{ if ($2 ~ /[0-9]\./) {print a,b[1]}; FS=" "}}'
    alf · 2010-04-15 04:34:28 16
  • Get IPv4 of eth0 for use with scripts

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


    5
    ifconfig eth0 | grep "inet " | cut -d ':' -f2 | awk '{print $1}'
    jaimerosario · 2010-06-29 00:06:08 4
  • Revert all modified files in an SVN repo


    5
    svn st | grep -e '^M' | awk '{print $2}' | xargs svn revert
    ethanmiller · 2010-08-11 14:24:05 3
  • Fibonacci numbers with awk

    recursive version, "pure" AWK Show Sample Output


    5
    awk 'func f(n){return(n<2?n:f(n-1)+f(n-2))}BEGIN{while(a<24){print f(a++)}}'
    unefunge · 2010-11-24 10:40:08 7
  • Lists all usernames in alphabetical order

    Save some CPU, and some PIDs. :)


    5
    awk -F ':' '{print $1 | "sort";}' /etc/passwd
    atoponce · 2011-12-20 12:46:52 3
  • Find duplicate UID in /etc/passwd

    You can use only awk


    5
    awk -F":" '!list[$3]++{print $3}' /etc/passwd
    richard · 2012-01-24 12:47:52 8
  • Found how how much memory in kB $PID is occupying in Linux

    The "proportional set size" is probably the closest representation of how much active memory a process is using in the Linux virtual memory stack. This number should also closely represent the %mem found in ps(1), htop(1), and other utilities. Show Sample Output


    5
    echo 0$(awk '/Pss/ {printf "+"$2}' /proc/$PID/smaps)|bc
    atoponce · 2013-09-26 18:20:22 10
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Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Redirect STDIN
Several times, I find myself hitting my up arrow, and changing the search term. Unfortunately, I find myself wasting too much time typing: $ grep kernel /var/log/messages Redirecting STDIN allows me to put the search term at the end so I less cursor movement to change what I'm searching for: $ < /var/log/messages grep kernel If you're using the emacs keyboard binding, then after you press your up arrow, press CTRL+w to erase the word. If this has already been submitted, I couldn't find it with the search utility.

Generate Random Passwords
If you want a password length longer than 6, changing the -c6 to read -c8 will give you 8 random characters instead of 6. To end up with a line-feed, use this with echo: # echo `< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c6` Modern systems need higher strenght, so add some special characters: # < /dev/urandom tr -dc '12345!@#$%qwertQWERTasdfgASDFGzxcvbZXCVB' | head -c8

Calculate pi with specific scale
a() function in bc is for arctangent, available if using -l option included.

Reset hosed terminal,
stty sane resets the tty to basic usable function. The ^J is a newline -- sometimes CR/LF interpretation is broken so use the ^J explicitly.

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Short and sweet output from dig(1)
Turn off almost all of dig's output except for what you'd see in a zone file. This can also be put into ~/.digrc.

watch iptables counters
Watch the number of packets/bytes coming through the firewall. Useful in setting up new iptables rules or chains. Use this output to reorder rules for efficiency.

Display a cool clock on your terminal
This command displays a clock on your terminal which updates the time every second. Press Ctrl-C to exit. A couple of variants: A little bit bigger text: $ watch -t -n1 "date +%T|figlet -f big" You can try other figlet fonts, too. Big sideways characters: $ watch -n 1 -t '/usr/games/banner -w 30 $(date +%M:%S)' This requires a particular version of banner and a 40-line terminal or you can adjust the width ("30" here).

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