All commands (14,187)

  • Command to build one or more network segments - with for

    Show Sample Output


    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
  • Command to build one or more network segments - with while

    Show Sample Output


    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
  • Partition a new disk as all one partition tagged as "LInux LVM"

    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
  • List system's users


    -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
  • Set default "New Page" as HTML in TextMate

    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
  • Restore a local drive from the image on remote host via ssh


    2
    ssh user@server 'dd if=sda.img' | dd of=/dev/sda
    newrain7803 · 2009-10-20 06:52:26 3
  • Backup a local drive into a file on the remote host via ssh


    12
    dd if=/dev/sda | ssh user@server 'dd of=sda.img'
    newrain7803 · 2009-10-20 06:47:01 7
  • Compression formats Benchmark

    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
  • Quickly Encrypt a file with gnupg and email it with mailx

    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
  • List your largest installed packages (on Debian/Ubuntu)

    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
  • To print a specific line from a file

    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 your largest installed packages (on Debian/Ubuntu)

    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
  • Copy recursivelly files of specific filetypes

    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
  • encode image to base64 and copy to clipboard

    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
  • Extract a bash function

    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
  • geoip lookup


    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
  • Battery real life energy vs predicted remaining plotted

    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
  • Localize provenance of current established connections

    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
  • Do you really believe on Battery Remaining Time? Confirm it from time to time!

    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
  • Show current weather for any US city or zipcode

    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
  • Get decimal ascii code from character

    printf treats first char after single ' as numeric equivalent


    1
    ord() { printf "%d\n" "'$1"; }
    zude · 2009-10-17 22:02:52 3
  • Make directories for and mount all iso files in a folder

    Show Sample Output


    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
  • Testing hard disk writing speed


    1
    time dd if=/dev/zero of=TEST bs=4k count=512000
    flojb · 2009-10-17 17:50:53 39
  • create iso image from a directory

    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
  • Get decimal ascii code from character

    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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Get your bash scripts to handle options (-h, --help etc) and spit out auto-formatted help or man page when asked!!
This will make your bash scripts better!! process-getopt is a wrapper around getopt(1) for bash that lets you define command line options (eg -h, --help) and descriptions through a single function call. These definitions are then used in runtime processing of command line options as well as in generating help and man pages. It also saves a little time in coding and in producing nicely formatted documentation. It is quite similar to GNU's argp in glibc for compiled languages and OptionParse for python. See: Linux Gazette article 162: http://tldp.org/LDP/LGNET/162/hepple.html, http://sourceforge.net/projects/process-getopt, http://bhepple.freeshell.org/oddmuse/wiki.cgi/process-getopt

Determine if photos have been rotated to portrait orientation instead of normal landscape orientation
Most people take photos in landscape orientation (wider than it is tall). Sometimes though you turn the camera sideways to capture a narrow/tall subject. Assuming you then manually rotate those picture files 90 degrees for proper viewing on screen or photo frame, you now have a mix of orientations in your photos directory. This command will print out the names of all the photos in the current directory whose vertical resolution is larger than its horizontal resolution (i.e. portrait orientation). You can then take that list of files and deal with them however you need to, like re-rotating back to landscape for consistent printing with all the others. This command requires the "identify" command from the ImageMagick command-line image manipulation suite. Sample output from identify: $ identify PICT2821.JPG PICT2821.JPG JPEG 1536x2048 1536x2048+0+0 8-bit DirectClass 688KB 0.016u 0:00.006

Connect to remote machine with other enconding charset

Measures download speed on eth0

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" }

cpu stress test
For each cpu set mask and then monitor your cpu infos. Temp,load avg. etc. For example for 2nd cpu or 2nd core taskset 0x00000002 yes > /dev/null & For example for 3rd cpu or 3rd core taskset 0x00000004 yes > /dev/null & For example for 4th cpu or 4th core taskset 0x00000008 yes > /dev/null & Monitor your cpu temp with this command if you want watch -n1 "acpi -t" Load avg. from top command top kerim@bayner.com http://www.bayner.com/

list files recursively by size

find text in a file
this will find text in the directory you specify and give you line where it appears.

Send pop-up notifications on Gnome
The title is optional. Options: -t: expire time in milliseconds. -u: urgency (low, normal, critical). -i: icon path. On Debian-based systems you may need to install the 'libnotify-bin' package. Useful to advise when a wget download or a simulation ends. Example: $ wget URL ; notify-send "Done"

Detect encoding of a text file
This command gives you the charset of a text file, which would be handy if you have no idea of the encoding.

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