Commands using sed (1,319)

  • This will generate 3 paragraphs with random text. Change the 3 to any number. Show Sample Output


    5
    lynx -source http://www.lipsum.com/feed/xml?amount=3|perl -p -i -e 's/\n/\n\n/g'|sed -n '/<lipsum>/,/<\/lipsum>/p'|sed -e 's/<[^>]*>//g'
    houghi · 2010-04-26 17:26:44 5
  • This command will format your alias or function to a single line, trimming duplicate white space and newlines and inserting delimiter semi-colons, so it continues to work on a single line. Show Sample Output


    5
    goclf() { type "$1" | sed '1d' | tr -d "\n" | tr -s '[:space:]'; echo }
    meathive · 2010-06-26 21:44:17 17
  • Tired copy paste to get opcode from objdump huh ? Get more @ http://gunslingerc0de.wordpress.com Show Sample Output


    5
    objdump -d ./PROGRAM|grep '[0-9a-f]:'|grep -v 'file'|cut -f2 -d:|cut -f1-6 -d' '|tr -s ' '|tr '\t' ' '|sed 's/ $//g'|sed 's/ /\\x/g'|paste -d '' -s |sed 's/^/"/'|sed 's/$/"/g'
    gunslinger_ · 2010-07-11 15:44:48 112
  • If you're going to use od, here's how to suppress the labels at the beginning. Also, it doesn't output the \x, hence the sed command at the end. Remove it for space separated hex values instead Show Sample Output


    5
    echo -n "text" | od -A n -t x1 |sed 's/ /\\x/g'
    camocrazed · 2010-07-14 15:31:36 8

  • 5
    sed -r "s:\x1B\[[0-9;]*[mK]::g"'
    roylez · 2010-07-22 05:37:25 6
  • Default output-file is "liveh.txt". This uses only BRE, in case you're using an older version of sed(1) that doesn't have support for ERE added. With a modern sed(1), to reduce false positive matches, you might do something like: liveh(){ tcpdump -lnnAs512 -i ${1-} tcp |sed 's/.*GET /GET /;s/.*Host: /Host: /;s/.*POST /POST /;/GET |Host: |POST /!d;/[\"'"'"]/d;/\.\./d;w '"${2-liveh.txt}"'' >/dev/null ;} Anyway, it's easy to clean up the output file with sed(1) later.


    5
    liveh(){ tcpdump -lnAs512 ${1-} tcp |sed ' s/.*GET /GET /;s/.*Host: /Host: /;s/.*POST /POST /;/[GPH][EOo][TSs]/!d;w '"${2-liveh.txt}"' ' >/dev/null ;} # usage: liveh [-i interface] [output-file] && firefox &
    argv · 2010-10-11 01:01:11 3
  • substitute "example" with desired string; tl = target language (en, fr, de, hu, ...); you can leave sl parameter as-is (autodetection works fine) Show Sample Output


    5
    wget -U "Mozilla/5.0" -qO - "http://translate.google.com/translate_a/t?client=t&text=translation+example&sl=auto&tl=fr" | sed 's/\[\[\[\"//' | cut -d \" -f 1
    sairon · 2011-03-06 13:46:16 109
  • Modify file in place to remove empty lines and create a backup of the original with the extension .bak Show Sample Output


    5
    sed -e '/^$/d' -i .bak filewithempty.lines
    donnoman · 2011-03-24 00:03:25 6
  • Gets a BOFH excuse from the BOFH excuse server (towel.blinkenlights.nl port 666), and passes it through sed and tr to get rid of telnet connection stuff. Show Sample Output


    5
    telnet towel.blinkenlights.nl 666 | sed "s/=== The BOFH Excuse Server ===//" | tr -d '\n' && echo
    hintss · 2011-03-31 05:50:57 3
  • This command outputs a table of sighting opportunities for the International Space Station. Find the URL for your city here: http://spaceflight.nasa.gov/realdata/sightings/ Show Sample Output


    5
    links -dump "http://spaceflight.nasa.gov/realdata/sightings/cities/view.cgi?country=United_States&region=Wisconsin&city=Portage" | sed -n '/--/,/--/p'
    eightmillion · 2011-05-03 12:15:56 7
  • usage: mem memcache-command [arguments] where memcache-command might be: set add get[s] append prepend replace delete incr decr cas stats verbosity version notes: exptime argument is set to 0 (no expire) flags argument is set to 1 (arbitrary)


    5
    mem(){ { case $1 in st*|[vgid]*) printf "%s " "$@";; *) dd if=$3 2>&1|sed '$!d;/^0/d;s/ .*//;s/^/'"$1"' '"$2"' 1 0 /; r '"$3"'' 2>/dev/null;;esac;printf "\r\nquit\r\n";}|nc -n 127.0.0.1 11211; }
    argv · 2011-06-17 06:39:07 6
  • Using the sed -i (inline), you can replace the beginning of the first line of a file without redirecting the output to a temporary location.


    5
    sed -i '1s/^/text to prepend\n/' file1
    xeor · 2011-06-25 12:02:11 14
  • - grep for the word in a files, use recursion (to find files in sub directories), and list only file matches -| xargs passes the results from the grep command to sed -sed -i uses a regular expression (regex) to evaluate the change: s (search) / search word / target word / g (global replace)


    5
    grep -lr -e '<oldword>' * | xargs sed -i 's/<oldword>/<newword>/g'
    o0110o · 2011-08-27 02:42:51 7
  • This should work with anything://url.whatever etc etc ;)


    5
    sed "s/\([a-zA-Z]*\:\/\/[^ ]*\)\(.*\)/\<a href=\"\1\"\>\1\<\/a\>\2/"
    c3w · 2012-01-04 02:08:29 7
  • pgrep foo may return several pids for process foobar footy01 etc. like this: 11427 12576 12577 sed puts "-p " in front and we pass a list to top: top -p 11427 -p 12576 -p 12577


    5
    top $(pgrep foo | sed 's|^|-p |g')
    michelsberg · 2012-06-14 15:13:00 3
  • This makes your commandlinefu.com's favorites appear as most recent commands in your history.


    5
    (cat ~/.bash_history;U='curl -s www.commandlinefu.com';$U/users/signin -c/tmp/.c -d'username=<USER>&password=<PASS>&submit=1'|$U/commands/favourites/json -b/tmp/.c|grep -Po 'nd":.*?[^\\]",'|sed -re 's/.*":"(.*)",/\1/g')>~/.h;HISTFILE=~/.h bash --login
    xenomuta · 2012-08-17 12:31:51 34
  • (Please see sample output for usage) script.bash is your script, which will be crypted to script.secure script.bash --> script.secure You can execute script.secure only if you know the password. If you die, your script dies with you. If you modify the startup line, be careful with the offset calculation of the crypted block (the XX string). Not difficult to make script editable (an offset-dd piped to a gpg -d piped to a vim - piped to a gpg -c directed to script.new ), but not enough space to do it on a one liner. Show Sample Output


    5
    echo "eval \"\$(dd if=\$0 bs=1 skip=XX 2>/dev/null|gpg -d 2>/dev/null)\"; exit" > script.secure; sed -i s:XX:$(stat -c%s script.secure): script.secure; gpg -c < script.bash >> script.secure; chmod +x script.secure
    rodolfoap · 2013-03-09 11:16:48 20
  • Automatically drops mount points that have non-numeric sizes (e.g. /proc). Tested in bash on Linux and AIX. Show Sample Output


    5
    for m in `df -P | awk -F ' ' '{print $NF}' | sed -e "1d"`;do n=`df -P | grep "$m$" | awk -F ' ' '{print $5}' | cut -d% -f1`;i=0;if [[ $n =~ ^-?[0-9]+$ ]];then printf '%-25s' $m;while [ $i -lt $n ];do echo -n '=';let "i=$i+1";done;echo " $n";fi;done
    drockney · 2013-07-29 20:12:39 6
  • Opposite: Convert an one-liner to script: foo() { <one-liner> ; } ... typeset -f foo ... unset -f foo


    5
    (sed 's/#.*//g'|sed '/^ *$/d'|tr '\n' ';'|xargs echo) < script.sh
    knoppix5 · 2013-10-26 23:23:51 16
  • Show the current load of the CPU as a percentage. Read the load from /proc/loadavg and convert it using sed: Strip everything after the first whitespace: sed -e 's/ .*//' Delete the decimal point: sed -e 's/\.//' Remove leading zeroes: sed -e 's/^0*//' Show Sample Output


    5
    sed -e 's/ .*//' -e 's/\.//' -e 's/^0*//' /proc/loadavg
    flatcap · 2014-04-18 19:12:05 10
  • weather 97405 Show Sample Output


    5
    weather() { curl -s "http://www.wunderground.com/q/zmw:$1.1.99999" | grep "og:title" | cut -d\" -f4 | sed 's/&deg;/ degrees F/'; }
    cadejscroggins · 2015-09-19 07:57:47 12
  • Very quick way to change a word in a file. I use it all the time to change variable names in my PHP scripts (sed -i 's/$oldvar/$newvar/g' index.php)


    4
    sed -i 's/OLD/NEW/g' FILE
    nanexcool · 2009-02-05 18:07:41 26
  • Very useful when the ssh key of a host has changed and ssh refuses to connect to the machine, while giving you the line number that has changed in ~/.ssh/known_hosts.


    4
    sed -i '10d' <somefile>
    raphink · 2009-02-16 15:05:29 130

  • 4
    sed '/./,$!d'
    grep · 2009-02-16 20:39:40 9
  • The ctrl+v,ctrl+m portion represents key presses that you should do. If you do it successfully you should see a ^M character appear.


    4
    sed 's/$/<ctrl+v><ctrl+m>/'
    SiegeX · 2009-02-16 20:53:05 12
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defragment files
Thanks to flatcap for optimizing this command. This command takes advantage of the ext4 filesystem's resistance to fragmentation. By using this command, files that were previously fragmented will be copied / deleted / pasted essentially giving the filesystem another chance at saving the file contiguously. ( unlike FAT / NTFS, the *nix filesystem always try to save a file without fragmenting it ) My command only effects the home directory and only those files with your R/W (read / write ) permissions. There are two issues with this command: 1. it really won't help, it works, but linux doesn't suffer much (if any ) fragmentation and even fragmented files have fast I/O 2. it doesn't discriminate between fragmented and non-fragmented files, so a large ~/ directory with no fragments will take almost as long as an equally sized fragmented ~/ directory The benefits i managed to work into the command: 1. it only defragments files under 16mb, because a large file with fragments isn't as noticeable as a small file that's fragmented, and copy/ delete/ paste of large files would take too long 2. it gives a nice countdown in the terminal so you know how far how much progress is being made and just like other defragmenters you can stop at any time ( use ctrl+c ) 3. fast! i can defrag my ~/ directory in 11 seconds thanks to the ramdrive powering the command's temporary storage bottom line: 1. its only an experiment, safe ( i've used it several times for testing ), but probably not very effective ( unless you somehow have a fragmentation problem on linux ). might be a placebo for recent windows converts looking for a defrag utility on linux and won't accept no for an answer 2. it's my first commandlinefu command

cut audio file

Perl Simple Webserver
First we accept a socket and fork the server. Then we overload the new socket as a code ref. This code ref takes one argument, another code ref, which is used as a callback. The callback is called once for every line read on the socket. The line is put into $_ and the socket itself is passed in to the callback. Our callback is scanning the line in $_ for an HTTP GET request. If one is found it parses the file name into $1. Then we use $1 to create an new IO::All file object... with a twist. If the file is executable("-x"), then we create a piped command as our IO::All object. This somewhat approximates CGI support. Whatever the resulting object is, we direct the contents back at our socket which is in $_[0].

Set random background image in gnome
Changes your desktop background image in gnome. Update the directory to wherever you keep your wallpapers. I like to create a sub-directory in my Wallpaper folder called "cycle" that I use to define the wallpapers I wish to loop in cron. ex: $ gconftool-2 -t str -s /desktop/gnome/background/picture_filename "$(find ~/Wallpapers/cycle -type f | shuf -n1)"

Remove newlines from output
Pipe any output to "grep ." and blank lines will not be printed.

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Get a brief overview of how many files and directories are installed
To start, you first need to make sure updatedb has been run/updatedb, and initialized the db: $ su -l root -c updatedb This locate command is provided through the mlocate package, installed by default on most GNU/Linux distributions. It's available on the BSDs as well. Not sure about support for proprietary UNIX systems. The output is self-explanatory- it provides an overview of how many directories and files are on your system.

Backup file, create dir and set perms in one shot
Prior to working on/modifying a file, use the 'install -m' command which can both copy files, create directories, and set their permissions at the same time. Useful when you are working in the public_html folder and need to keep the cp'd file hidden.

One-liner to generate Self-Signed SSL Certificate+Key without any annoying prompts or CSRs
Handy if you want to quickly generate a self-signed certificate. Also can be used in your automated scripts for generating quick-use certificates.

To find which host made maximum number of specific tcp connections
This command is primarily going to work on linux boxes. and needs to be changed, for example IP=10\.194\.194\.2 PORT=389


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