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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Test network speed without wasting disk
The above command will send 4GB of data from one host to the next over the network, without consuming any unnecessary disk on either the client nor the host. This is a quick and dirty way to benchmark network speed without wasting any time or disk space. Of course, change the byte size and count as necessary. This command also doesn't rely on any extra 3rd party utilities, as dd, ssh, cat, /dev/zero and /dev/null are installed on all major Unix-like operating systems.

File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.

Make shell (script) low priority. Use for non interactive tasks

Get notified when a job you run in a terminal is done, using NotifyOSD
This is an alias you can add to your .bashrc file to get notified when a job you run in a terminal is done. example of use sleep 20; alert Source:http://www.webupd8.org/2010/07/get-notified-when-job-you-run-in.html

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"

determine if a shared library is compiled as 32bit or 64bit
Determines the flavor of a shared library by looking at the addresses of its exposed functions and seeing if they are 16 bytes or 8 bytes long. The command is written so the library you are querying is passed to a variable up font -- it would be simple to convert this to a bash function or script using this format.

View disk usage

Set pcap & SUID Bit for priv. network programs (like nmap)

How to copy CD/DVD into hard disk (.iso)
A dear friend of mine asked me how do I copy a DVD to your hard drive? If you want to make a copy of the ISO image that was burned to a CD or DVD, insert that medium into your CD/DVD drive and (assuming /dev/cdrom is associated with your computer?s CD drive) type the following command

Get your external IP address


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