All commands (14,187)


  • 0
    seg() { for b in $(echo $1); do for x in $(seq 10); do echo $b.$x; done; done }
    Waldirio · 2009-10-20 18:14:25 3

  • 0
    seg() { echo -e "$1" | while read LINE; do for b in $(seq 10); do echo $LINE.$b; done; done; }
    Waldirio · 2009-10-20 17:45:43 3
  • This is a bit hacky, but if you're setting up a bunch of new LUNs, it can save a bunch of time. Also check out sfdisk. The fdisk will fail if, for example, a partition table already exists.


    -1
    echo -e "n\np\n1\n\n\nt\n8e\nw" | fdisk /dev/sdX
    sud0er · 2009-10-20 16:21:54 5

  • -12
    teste.txt < cut -d : -f 1,5 /etc/passwd | tr : \\t | tr a-z A-Z | cat teste.txt
    osvaldofilho · 2009-10-20 14:53:38 9
  • When you press "cmd+n" in TextMate, you can have "HTML" language as default document format... You can also define other languages too. You need to know the UUID of your language bundle.


    -1
    defaults write com.macromates.textmate OakDefaultLanguage 17994EC8-6B1D-11D9-AC3A-000D93589AF6
    vigo · 2009-10-20 07:10:34 4

  • 2
    ssh user@server 'dd if=sda.img' | dd of=/dev/sda
    newrain7803 · 2009-10-20 06:52:26 3

  • 12
    dd if=/dev/sda | ssh user@server 'dd of=sda.img'
    newrain7803 · 2009-10-20 06:47:01 7
  • See: http://imgur.com/JgjK2.png for example. Do some serious benchmarking from the commandline. This will write to a file with the time it took to compress n bytes to the file (increasing by 1). Run: gnuplot -persist <(echo "plot 'lzma' with lines, 'gzip' with lines, 'bzip2' with lines") To see it in graph form.


    3
    for a in bzip2 lzma gzip;do echo -n>$a;for b in $(seq 0 256);do dd if=/dev/zero of=$b.zero bs=$b count=1;c=$(date +%s%N);$a $b.zero;d=$(date +%s%N);total=$(echo $d-$c|bc);echo $total>>$a;rm $b.zero *.bz2 *.lzma *.gz;done;done
    matthewbauer · 2009-10-20 01:00:51 5
  • This is a quick and easy way of encrypting files in a datastream, without ever really creating an output file from gpg. Useful with cron also, when file(s) have to be sent based on a set schedule.


    3
    cat private-file | gpg2 --encrypt --armor --recipient "Disposable Key" | mailx -s "Email Subject" user@email.com
    slashdot · 2009-10-19 20:38:37 4
  • Use the hold space to preserve lines until data is needed.


    -3
    sed -ne '/^Package: \(.*\)/{s//\1/;h;};/^Installed-Size: \(.*\)/{s//\1/;G;s/\n/ /;p;}' /var/lib/dpkg/status | sort -rn
    arcege · 2009-10-19 19:01:17 24
  • I don't know if it's better but works fine :)


    -5
    awk '{if (NR == 3) print}' <file>
    yooreck · 2009-10-19 15:58:09 5
  • List packages and their disk usage in decreasing order. This uses the "Installed-Size" from the package metadata. It may differ from the actual used space, because e.g. data files (think of databases) or log files may take additional space. Show Sample Output


    0
    perl -ne '$pkg=$1 if m/^Package: (.*)/; print "$1\t$pkg\n" if m/^Installed-Size: (.*)/;' < /var/lib/dpkg/status | sort -rn | less
    hfs · 2009-10-19 12:55:59 7
  • Copying only wmv and mpg files recursively from to


    1
    rsync -rvtW --progress --include='*.wmv' --include='*.mpg' --exclude='*.*' <sourcedir> <destdir>
    MauricioVieira · 2009-10-19 10:38:11 4
  • I use it for embedding images in CSS for Stylish, the Firefox addon. Thought it might be useful to others.


    1
    uuencode -m $1 /dev/stdout | sed '1d' | sed '$d' | tr -d '\n' | xclip -selection clipboard
    caliburning · 2009-10-19 09:03:09 4
  • I often need to extract a function from a bash script and this command will do it. Show Sample Output


    8
    sed -n '/^function h\(\)/,/^}/p' script.sh
    haivu · 2009-10-19 07:55:35 33

  • 4
    geoip(){curl -s "http://www.geody.com/geoip.php?ip=${1}" | sed '/^IP:/!d;s/<[^>][^>]*>//g' ;}
    twfcc · 2009-10-19 05:48:07 17
  • This time I added a print to reemaining energy, every minute, time stamped. The example shown here is complete and point to large discrepancies as time passes, converging to accuracy near the end. Show Sample Output


    1
    echo start > battery.txt; watch -n 60 'date >> battery.txt ; acpi -b >> battery.txt'
    m33600 · 2009-10-19 05:28:15 4
  • Sample command to obtain a list of geographic localization for established connections, extracted from netstat. Need geoiplookup command ( part of geoip package under CentOS) Show Sample Output


    3
    for i in $(netstat --inet -n|grep ESTA|awk '{print $5}'|cut -d: -f1);do geoiplookup $i;done
    servermanaged · 2009-10-18 20:41:47 4
  • Fully recharge your computer battery and start this script. It will create or clean the file named battery.txt, print a start on it and every minute it will append a time stamp to it. Batteries last few hours, and each hour will have 60 lines of time stamping. Really good for assuring the system was tested in real life with no surprises. The last time stamp inside the battery.txt file is of interest. It is the time the computer went off, as the battery was dead! Turn on your computer after that, on AC power of course, and open battery.txt. Read the first and last time stamps and now you really know if you can trust your computer sensors. If you want a simple line of text inside the battery.txt file, use this: watch -n 60 'date > battery.txt' The time of death will be printed inside Show Sample Output


    0
    echo start > battery.txt; watch -n 60 'date >> battery.txt'
    m33600 · 2009-10-18 07:00:26 4
  • Scrape the National Weather Service Show Sample Output


    4
    weather() { lynx -dump "http://mobile.weather.gov/port_zh.php?inputstring=$*" | sed 's/^ *//;/ror has occ/q;2h;/__/!{x;s/\n.*//;x;H;d};x;s/\n/ -- /;q';}
    zude · 2009-10-17 23:47:47 4
  • printf treats first char after single ' as numeric equivalent


    1
    ord() { printf "%d\n" "'$1"; }
    zude · 2009-10-17 22:02:52 3

  • 2
    for file in *.iso; do mkdir `basename $file | awk -F. '{print $1}'`; sudo mount -t iso9660 -o loop $file `basename $file | awk -F. '{print $1}'`; done
    jaymzcd · 2009-10-17 20:07:31 4

  • 1
    time dd if=/dev/zero of=TEST bs=4k count=512000
    flojb · 2009-10-17 17:50:53 39
  • create iso image from directory . Usefull for virtualised machine To create CD ISO image of directories that contain long file name or non-8.3 format (particularly if you want to burn the CD image for use in Windows system), use the -J option switch that generates Joliet directory records in addition to regular iso9660 file names. For example, to create CD image of Vista SP1 directory: mkisofs -o VitaSP1.iso -J VistaSP1 Show Sample Output


    8
    mkisofs -o XYZ.iso XYZ/
    eastwind · 2009-10-17 16:28:47 53
  • the shortest command for character 'a' i know Show Sample Output


    1
    echo -n a | od -d | sed -n "s/^.* //gp"
    stf42 · 2009-10-17 15:46:00 7
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Show bash's function definitions you defined in .bash_profile or .bashrc
If you omit the function name, the command will display all definitions

Create full backups of individual folders using find and tar-gzip
Problem: I wanted to backup user data individually. In this example, all user data is located in "/mnt/storage/profiles", and about 25 folders inside, each with a username ( /mnt/storage/profiles/mike; /mnt/storage/profiles/lucy ...) I need each individual folder backed up, not the whole "/mnt/storage/profiles". So, using find while excluding directories depth and creating two variables (tarfile=username & desdir=destination), tar will create a .tgz file for each folder, resulting in a "mike_full.tgz" and "lucy_full.tgz".

copy remote ssh session output to local clipboard
ssh from local to remote and pipe output of file to the local clipboard

ssh -A user@somehost
the -A argument forwards your ssh private keys to the host you're going to. Useful in some scenarios where you have to hop to one server, and then login to another using a private key.

Start another X session in a window
You might have Xnest (older) rather than Xephyr. You can experiment with other desktops eg: startx /usr/bin/start-kde -- /usr/bin/Xephyr :2 You can start X on a remote machine (although I'd recommend vnc for anything slower than a LAN): startx /usr/bin/ssh -X gnome-session -- /usr/bin/Xephyr :2 Or just start another X session locally talking to the remote backend:

Who invoked me? / Get parent command
Get the name of the parent command. This might be helpful, if you need to react on that information. E. g. a script called directly via ssh has got sshd as parent, manually invoked the parent process will probably be bash

en/decrypts files in a specific directory
To decrypt the files replace "ccenrypt" with "ccdecrypt. ccrypt(1) must be installed. It uses the AES (Rijndael) block cipher. To make it handier create an alias.

Replicate a directory structure dropping the files
Here is how to replicate the directory structure in the current directory to a destination directory (given by the variable DESTDIR), without copying the files.

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"

sort list of email addresses by domain.tld
email random list can be created here: https://www.randomlists.com/email-addresses


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