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 8
  • 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 3
  • 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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Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Visit wikileaks.com
Who needs a DNS server

resume other user's screen session via su, without pty error
Normally, if you su to another user from root and try to resume that other user's screen session, you will get an error like "Cannot open your terminal '/dev/pts/0' - please check." This is because the other user doesn't have permission for root's pty. You can get around this by running a "script" session as the new user, before trying to resume the screen session. Note you will have to execute each of the three commands separately, not all on the same line as shown here. Credit: I found this at http://www.hjackson.org/blog/archives/2008/11/29/cannot-open-your-terminal-dev-pts-please-check.

Place the NUM-th argument of the most recent command on the shell
After executing a command with multiple arguments like cp ./temp/test.sh ~/prog/ifdown.sh you can paste any argument of the previous command to the console, like ls -l ALT+1+. is equivalent to ls -l ./temp/test.sh ALT+0+. stands for command itself ('ls' in this case) Simple ALT+. cycles through last arguments of previous commands.

Get your external IP address without curl
Curl is not installed by default on many common distros anymore. wget always is :) $ wget -qO- ifconfig.me/ip

power off system in X hours form the current time, here X=2

awk date convert
Convert readable date/time with `date` command

Alias TAIL for automatic smart output
Run the alias command, then issue $ps aux | tail and resize your terminal window (putty/console/hyperterm/xterm/etc) then issue the same command and you'll understand. $ ${LINES:-`tput lines 2>/dev/null||echo -n 12`} Insructs the shell that if LINES is not set or null to use the output from `tput lines` ( ncurses based terminal access ) to get the number of lines in your terminal. But furthermore, in case that doesn't work either, it will default to using the default of 80. The default for TAIL is to output the last 10 lines, this alias changes the default to output the last x lines instead, where x is the number of lines currently displayed on your terminal - 7. The -7 is there so that the top line displayed is the command you ran that used TAIL, ie the prompt. Depending on whether your PS1 and/or PROMPT_COMMAND output more than 1 line (mine is 3) you will want to increase from -2. So with my prompt being the following, I need -7, or - 5 if I only want to display the commandline at the top. ( http://www.askapache.com/linux/bash-power-prompt.html ) 275MB/748MB [7995:7993 - 0:186] 06:26:49 Thu Apr 08 [askapache@n1-backbone5:/dev/pts/0 +1] ~ $ In most shells the LINES variable is created automatically at login and updated when the terminal is resized (28 linux, 23/20 others for SIGWINCH) to contain the number of vertical lines that can fit in your terminal window. Because the alias doesn't hard-code the current LINES but relys on the $LINES variable, this is a dynamic alias that will always work on a tty device.

generate a unique and secure password for every website that you login to
usage: sitepass MaStErPaSsWoRd example.com description: An admittedly excessive amount of hashing, but this will give you a pretty secure password, It also eliminates repeated characters and deletes itself from your command history. tr '!-~' 'P-~!-O' # this bit is rot47, kinda like rot13 but more nerdy rev # this avoids the first few bytes of gzip payload, and the magic bytes.

Route outbound SMTP connections through a addtional IP address rather than your primary


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