All commands (14,187)

  • Felt like I need to win the lottery, and wrote this command so I train and develop my guessing abilities. Show Sample Output


    13
    A=1;B=100;X=0;C=0;N=$[$RANDOM%$B+1];until [ $X -eq $N ];do read -p "N between $A and $B. Guess? " X;C=$(($C+1));A=$(($X<$N?$X:$A));B=$(($X>$N?$X:$B));done;echo "Took you $C tries, Einstein";
    rodolfoap · 2009-12-16 13:24:23 140
  • Check general system error on AIX


    1
    errpt -a | more
    marousan · 2009-12-16 12:07:16 3
  • I wanted to create a copy of my whole laptop disk on an lvm disk of the same size. First I created the logical volume: lvcreate -L120G -nlaptop mylvms SOURCE: dd if=/dev/sda bs=16065b | netcat ip-target 1234 TARGET: nc -l -p 1234 | dd of=/dev/mapper/mylvms-laptop bs=16065b to follow its process you issue the following command in a different terminal STATS: on target in a different terminal: watch -n60 -- kill -USR1 $(pgrep dd) (see http://www.commandlinefu.com/commands/view/4356/output-stats-from-a-running-dd-command-to-see-its-progress)


    7
    SOURCE: dd if=/dev/sda bs=16065b | netcat ip-target 1234 TARGET: netcat -l -p 1234 | dd of=/dev/mapper/laptop bs=16065b STATS on target: watch -n60 -- kill -USR1 $(pgrep dd)
    bw · 2009-12-16 10:51:06 10
  • if you start a large dd and forgot about statistics, but you still wonder what the progress is this command in an OTHER terminal will show you the way. NOTE: the watch command by itself will not output anything NOTE: the kill command will not kill the process Show Sample Output


    2
    watch -n60 --kill -USR1 $(pgrep dd)
    bw · 2009-12-16 10:35:28 4
  • If you give tar a list of filenames, it will not add the directories, so if you don't care about directory ownership or permissions, you can save some space. Tar will create directories as necessary when extracting. This command is limited by the maximum supported size of the argument list, so if you are trying to tar up the whole OS for instance, you may just get "Argument list too long".


    3
    tar -cvzf arch.tgz $(find /path/dir -not -type d)
    pysquared · 2009-12-15 13:46:54 6
  • Tar - Compress by excluding folders Show Sample Output


    -1
    tar -cvf /path/dir.tar /path/dir* --exclude "/path/dir/name" --exclude "/path/dir/opt"
    sandeepverma · 2009-12-15 09:48:41 3

  • 8
    COL=$(( $(tput cols) / 2 )); clear; tput setaf 2; while :; do tput cup $((RANDOM%COL)) $((RANDOM%COL)); printf "%$((RANDOM%COL))s" $((RANDOM%2)); done
    sputnick · 2009-12-15 02:48:28 10
  • This can show all ls colors, with a demo.


    8
    echo $LS_COLORS | sed 's/:/\n/g' | awk -F= '!/^$/{printf("%s \x1b[%smdemo\x1b[0m\n",$0,$2)}'
    bones7456 · 2009-12-15 01:17:46 7
  • We force IPv4, compress the stream, specify the cypher stream to be Blowfish. I suppose you could use aes256-ctr as well for cypher spec. I'm of course leaving out things like master control sessions and such as that may not be available on your shell although that would speed things up as well.


    18
    ssh -4 -C -c blowfish-cbc
    vxbinaca · 2009-12-15 00:30:53 34
  • Not everyone reads manpages. Aliasing this command will help with the task of doing audits with RKhunter. It will check for the latest version, update the definitions and then run a check on the system. Hint: alias that in your .bashrc to make life for your fingers easier.


    2
    rkhunter --versioncheck --update --propupd --check
    vxbinaca · 2009-12-15 00:23:45 4
  • This command is a great way to check to see if acpi is doing damage to your disks by agressivly parking the read arm and wearing down it's life. As you can see, mine has lost half its life. I'm sure this could be shortened though somehow. It will use smartctl to dump the stats and then grep out just the temperature and load cycles for the disk (a load cycle is when a the read arm comes out of park and wears on the drive). Show Sample Output


    2
    watch -d 'sudo smartctl -a /dev/sda | grep Load_Cycle_Count ; sudo smartctl -a /dev/sda | grep Temp'
    vxbinaca · 2009-12-15 00:15:24 5
  • FLAC's built in integrity checks are far more useful then devising a scheme to use MD5 sum files. This will check all the FLAC in a directory and output only errors. Remove the "s" after the "t" and it will be somewhat verbose in the check.


    1
    flac -ts *.flac
    vxbinaca · 2009-12-15 00:07:51 5
  • This command is meant to be used to make a lightweight backup, for when you want to know which files might be missing or changed, but you don't care about their contents (because you have some way to recover them). Explanation of parts: "ls -RFal /" lists all files in and below the root directory, along with their permissions and some other metadata. I think sudo is necessary to allow ls to read the metadata of certain files. "| gzip" compresses the result, from 177 MB to 16 MB in my case. "> all_files_list.txt.gz" saves the result to a file in the current directory called all_files_list.txt.gz. This name can be changed, of course. Show Sample Output


    2
    sudo ls -RFal / | gzip > all_files_list.txt.gz
    roryokane · 2009-12-14 21:40:56 3
  • Remove security from PDF document using this very simple command on Linux and OSX. You need ghostscript for this baby to work.


    47
    gs -q -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -sOutputFile=OUTPUT.pdf -c .setpdfwrite -f INPUT.pdf
    deijmaster · 2009-12-14 21:30:22 27
  • The above url contains over 6700 of the common ad websites. The command just pastes these into your /etc/hosts. Show Sample Output


    7
    wget -q -O - http://someonewhocares.org/hosts/ | grep ^127 >> /etc/hosts
    torrid · 2009-12-14 17:11:16 8
  • Useful if a different user cannot access some directory and you want to know which directory on the way misses the x bit. Show Sample Output


    2
    dir=$(pwd); while [ ! -z "$dir" ]; do ls -ld "$dir"; dir=${dir%/*}; done; ls -ld /
    hfs · 2009-12-14 14:38:11 3
  • Displays a scrolling banner which loops until you hit Ctrl-C to terminate it. Make sure you finish your banner message with a space so it will loop nicely.


    11
    while [ 1 ]; do banner 'ze missiles, zey are coming! ' | while IFS="\n" read l; do echo "$l"; sleep 0.01; done; done
    craigds · 2009-12-14 07:40:07 10
  • If you want all the URLs from all the sessions, you can use : perl -lne 'print for /url":"\K[^"]+/g' ~/.mozilla/firefox/*/sessionstore.js Thanks to tybalt89 ( idea of the "for" statement ). For perl purists, there's JSON and File::Slurp modules, buts that's not installed by default.


    0
    perl -lne 'print for /url":"\K[^"]+/g' $(ls -t ~/.mozilla/firefox/*/sessionstore.js | sed q)
    sputnick · 2009-12-14 00:51:54 2
  • blue and yellow colored bash prompt for a Hanukkah celebration on your box


    3
    export PS1="\e[0;34m[\u\e[0;34m@\h[\e[0;33m\w\e[0m\e[0m\e[0;34m]#\e[0m "
    decept · 2009-12-13 18:35:06 8
  • This command, taken from play's manual page, plays a synthesized guitar tone for each of the strings on a standard tuned guitar. The command "play" is a part of the package "sox".


    18
    for n in E2 A2 D3 G3 B3 E4;do play -n synth 4 pluck $n repeat 2;done
    eightmillion · 2009-12-13 06:57:26 32

  • 11
    cpan -r
    sputnick · 2009-12-13 02:54:22 9
  • Thanks to comment if that works or not... If you have already typed that snippet or you know you already have IO::Interface::Simple perl module, you can type only the last command : perl -e 'use IO::Interface::Simple; my $ip=IO::Interface::Simple->new($ARGV[0]); print $ip->address,$/;' <INTERFACE> ( The first perl command will install the module if it's not there already... )


    1
    x=IO::Interface::Simple; perl -e 'use '$x';' &>/dev/null || cpan -i "$x"; perl -e 'use '$x'; my $ip='$x'->new($ARGV[0]); print $ip->address,$/;' <INTERFACE>
    sputnick · 2009-12-13 02:23:40 36
  • Knowing when a filesystem is created , you can deduce when an operating system was installed . find filesystem device (/dev/) informations by using the cat /etc/fstab command. Show Sample Output


    7
    dumpe2fs -h /dev/DEVICE | grep 'created'
    eastwind · 2009-12-12 14:47:33 14

  • 4
    du -sch ./*
    enderst · 2009-12-12 05:10:40 3

  • 1
    ffmpeg -i Your_video_file -s 320x240 FILE.flv
    eastwind · 2009-12-12 00:28:10 4
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quickly change all .html extensions on files in folder to .htm

Block known dirty hosts from reaching your machine
Blacklisted is a compiled list of all known dirty hosts (botnets, spammers, bruteforcers, etc.) which is updated on an hourly basis. This command will get the list and create the rules for you, if you want them automatically blocked, append |sh to the end of the command line. It's a more practical solution to block all and allow in specifics however, there are many who don't or can't do this which is where this script will come in handy. For those using ipfw, a quick fix would be {print "add deny ip from "$1" to any}. Posted in the sample output are the top two entries. Be advised the blacklisted file itself filters out RFC1918 addresses (10.x.x.x, 172.16-31.x.x, 192.168.x.x) however, it is advisable you check/parse the list before you implement the rules

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

Convert files from DOS line endings to UNIX line endings
Here "^M" is NOT "SHIFT+6" and "M". Type CTRL+V+M to get it instead. Its shortest and easy. And its sed!, which is available by default in all linux flavours.. no need to install extra tools like fromdos.

get a desktop notification from the terminal
tired of switching to the console to check if some command has finished yet? if notify-send does not work on your box try this one... e.g. rsync -av -e /usr/bin/lsh $HOME slowconnection.bar:/mnt/backup ; z (now fire up X, do something useful, get notified if this stuff has finished).

Undo mkdir -p new/directory/path
Removes all directories on given path, working from right to left, and stops when reaching a non-empty directory Counterpart of $ mkdir -p new/directory/path Shortcut (must be issues as next command immediately after mkdir): $ ^mk^rm ( see http://www.commandlinefu.com/commands/view/19/runs-previous-command-but-replacing )

Quick and Temporary Named Commands
* Add comment with # in your command * Later you can search that command on that comment with CTRL+R In the title command, you could search it later by invoking the command search tool by first typing CTRL+R and then typing "revert"

Reverse ssh
Both hosts must be running ssh and also the outside host must have a port forwarded to port 22.

Find the package that installed a command

Outputs each arg on its own line
This can be useful for transforming command-line args into input for xargs (one per line). This can also be done with ls if the args are filenames, but that's getting awfully close to Useless Use of Cat territory (http://partmaps.org/era/unix/award.html).


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