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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FAST Search and Replace for Strings in all Files in Directory
I needed a way to search all files in a web directory that contained a certain string, and replace that string with another string. In the example, I am searching for "askapache" and replacing that string with "htaccess". I wanted this to happen as a cron job, and it was important that this happened as fast as possible while at the same time not hogging the CPU since the machine is a server. So this script uses the nice command to run the sh shell with the command, which makes the whole thing run with priority 19, meaning it won't hog CPU processing. And the -P5 option to the xargs command means it will run 5 separate grep and sed processes simultaneously, so this is much much faster than running a single grep or sed. You may want to do -P0 which is unlimited if you aren't worried about too many processes or if you don't have to deal with process killers in the bg. Also, the -m1 command to grep means stop grepping this file for matches after the first match, which also saves time.

Equivalent to ifconfig -a in HPUX
not shown ifconfig error

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Watch the National Debt clock
The idea was originally stolen from Linux Journal. 'wget' pulls the debt clock and 'sed' reformats it for general consumption. Prefacing the command with 'watch' simply sets an interval - in this case every 10 seconds.

Never rewrites a file while copying (or moving)
Allows you to preserve your files when using cp, mv, ln, install or patch. When the target file exists, it will generate a file named XXX.~N~ (N is an auto-incremental number) instead of deleting the target file.

Print all commands of a user on commandlinefu.com
This utilizes the Requests and BeautifulSoup libraries in Python to retrieve a user page on commandlinefu, parse it (error-tolerant) and extract all the lines of the following format: gzip * To print them, a list comprehension is used to iterate over the values, and join() is called on a newline character.

List all symbolic links in a directory matching a string
Finds all symbolic links in the specified directory which match the specified string pattern. I used this when upgrading from an Apple-supported version of Java 6 (1.6.0_65) to an Oracle-supported version (1.7.0_55) on Mac OS X 10.8.5 to find out which executables were pointing to /System/Library/Frameworks/JavaVM.framework/Versions/Current/Commands (Apple version) vs. /Library/Java/JavaVirtualMachines/jdk1.7.0_55.jdk/Contents/Home/bin (Oracle version). However, it appears the current JDK installation script already takes care of modifying the links.

Be notified about overheating of your CPU and/or motherboard
You'll be notified if your core 1 temperature exceeds 50 degrees, you can change the monitored device by editing the "Core 1" or change the critical temperature by editing the "-gt 50" part. Note: you must have lm-sensors installed and configured in order to get this command working.

Generate a random password 30 characters long

Display the inodes number of /


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