Commands by totti (87)

  • Matched string reference in replacement text

    Use matched data and some other as replacement data Show Sample Output


    0
    echo "abcde" | sed 's/./& /g'
    totti · 2011-08-26 16:54:26 7
  • Notify on Battery power

    Works on Laptops, Desktop having communication b/w UPS & CPU Show Sample Output


    0
    NotifyOnBATTERY () { while :; do on_ac_power||notify-send "Running on BATTERY"; sleep 1m; done }
    totti · 2011-08-26 11:54:16 7
  • Download a set of files that are numbered


    0
    for i in `seq -w 1 50`; do wget --continue \ http://commandline.org.uk/images/posts/animal/$i.jpg; done
    totti · 2011-08-19 20:06:16 5
  • Get full from half remembered commands

    Show all commands having the part known by you. Eg: apropos pdf | less Show Sample Output


    2
    apropos <part_rember> | less
    totti · 2011-08-19 19:34:57 6
  • Alternative for basename using grep to extract file name

    fileName /path/to/file.ext quivalent to basename /path/to/file.ext Show Sample Output


    -1
    fileName() { echo "$1" | grep -o "[^/]*$"; }
    totti · 2011-08-19 18:16:22 3
  • Boot block devices as virtual devices in Virtual Box

    eg: VBoxManage internalcommands createrawvmdk -filename ~/.VBox_sdc.vmdk -rawdisk /dev/sdc In order to start virtual box using block devices, ( Or to boot from it) run as ROOT sudo VirtualBox Then add & select the vmdk file as a device. At last Start the virtual box. - This cmd needs to run once for a device. - See command 8936 to run with out using ROOT power and easy handling of Virtual m/c


    0
    VBoxManage internalcommands createrawvmdk -filename [path/to/file/name.vmdk] -rawdisk /dev/[block_device]
    totti · 2011-08-19 14:26:22 8
  • Find all videos under current directory using MIME a.k.a not using extension

    Videos are found using their MIME type. Thus no need to for an extension for the video file. This is a efficent version of "jnash" cmd (4086). Thanks for jnash. This cmd will only show video files while his cmd show files having "video" anywhere in path. Show Sample Output


    1
    allVideos() { find ./ -type f -print0 | xargs -0 file -iNf - | grep ": video/" | cut -d: -f1; }
    totti · 2011-08-19 11:58:59 3
  • What is the use of this switch ?

    Find the usage of a switch with out searching through the entire man page. Usage: manswitch [cmd] [switch] Eg: manswitch grep silent ____________________________ In simple words man <cmd> | grep "\-<switch>" Eg: man grep | grep "\-o" This is not a standard method but works. Show Sample Output


    1
    manswitch() { man $1 | grep -A5 "^ *\-$2"; }
    totti · 2011-08-19 08:36:54 5
  • Sort output by column

    (separator = $IFS)


    2
    ps aux | sort -nk 6
    totti · 2011-08-16 11:04:45 3
  • Check if your webserver supports gzip compression with curl


    6
    curl -I -H "Accept-Encoding: gzip,deflate" http://example.org
    totti · 2011-08-16 10:32:01 4
  • Highlight network TX, RX information change


    5
    watch -n 2 -d '/sbin/ifconfig eth0'
    totti · 2011-08-16 10:29:34 4
  • Boot from a block device without giving root privilege to Virtual Box

    Usage: VBoxBlockBoot [Virtual_Machine] [Block_device] Eg: VBoxBlockBoot WinXP /dev/sdc In another words vm=usb; usb=sdc;sudo umount /dev/$usb* ; sudo chmod 777 /dev/$usb ; VBoxManage storageattach $vm --medium ~/raw-HD-4-VB/$usb.vmdk --type hdd --storagectl "IDE Controller" --device 0 --port 0 ; VBoxManage startvm $vm Where vm --> Name of the virtual machine to start usb --> Block device to use. (/dev/sdc) This can used after setup up a boot loader on to my USB pen drive or HDD (After creating Live USB). Here root privilege is needed but not granted to Virtual Box. Thus we can access all our VM.( If we run VBox as root we can't access our VMs). Root privilege is used to - Unmount the storage device - Chmod to full access (777) Requirements:- 1. Device information file (rawvmdk file) created by the following command. Need to run only once. Not bad to run many. VBoxCreateRawDisk() { VBoxManage internalcommands createrawvmdk -filename ~/.rawHD4VB_`basename "$1"`.vmdk -rawdisk "$1"; } 2. Root privilege to umount & chmod 3. Real storage medium (ie /dev/*) (Non-virtual such as USB HD, pen drive, a partition) 4. A virtual m/c already available (here "usb") vm=usb; usb=sdc;sudo umount /dev/$usb* ; sudo chmod 777 /dev/$usb ; VBoxManage storageattach $vm --medium ~/raw-HD-4-VB/$usb.vmdk --type hdd --storagectl "IDE Controller" --device 0 --port 0 ; VBoxManage startvm $vm VBoxBlockBoot() { sudo umount "$2"*; sudo chmod 777 "$2"; VBoxManage storageattach "$1" --medium ~/.rawHD4VB_`basename "$2"`.vmdk --type hdd --storagectl "IDE Controller" --device 0 --port 0 ; VBoxManage startvm "$1"; } Show Sample Output


    0
    VBoxBlockBoot() { sudo umount "$2"*; sudo chmod 777 "$2"; VBoxManage storageattach "$1" --medium ~/.rawHD4VB_`basename "$2"`.vmdk --type hdd --storagectl "IDE Controller" --device 0 --port 0 ; VBoxManage startvm "$1";}
    totti · 2011-07-29 13:04:19 4
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Prepare a commandlinefu command.
This command will format your alias or function to a single line, trimming duplicate white space and newlines and inserting delimiter semi-colons, so it continues to work on a single line.

Stop Flash from tracking everything you do.
Brute force way to block all LSO cookies on a Linux system with the non-free Flash browser plugin. Works just fine for my needs. Enjoy.

Enter parameter if empty (script becomes interactive when parameters are missing)
Can be used for command line parameters too. If you have a more complicated way of entering values (validation, GUI, ...), then write a function i.e. EnterValue() that echoes the value and then you can write: $ param=${param:-$(EnterValue)}

Change user within ssh session retaining the current MIT cookie for X-forwarding
When you remotely log in like "ssh -X userA:host" and become a different user with "su UserB", X-forwarding will not work anymore since /home/UserB/.Xauthority does not exist. This will use UserA's information stored in .Xauthority for UserB to enable X-forwarding. Watch http://prefetch.net/blog/index.php/2008/04/05/respect-my-xauthority/ for details.

Cut out a piece of film from a file. Choose an arbitrary length and starting time.
With: -vcodec, you choose what video codec the new file should be encoded with. Run ffmpeg -formats E to list all available video and audio encoders and file formats. copy, you choose the video encoder that just copies the file. -acodec, you choose what audio codec the new file should be encoded with. copy, you choose the audio encoder that just copies the file. -i originalfile, you provide the filename of the original file to ffmpeg -ss 00:01:30, you choose the starting time on the original file in this case 1 min and 30 seconds into the film -t 0:0:20, you choose the length of the new film newfile, you choose the name of the file created. Here is more information of how to use ffmpeg: http://www.ffmpeg.org/ffmpeg-doc.html

Validating a file with checksum
Makes sure the contents of "myfile" are the same contents that the author intended given the author's md5 hash of that file ("c84fa6b830e38ee8a551df61172d53d7").

find files ignoring .svn and its decendents

list files recursively by size

Query wikipedia over DNS

Network Discover in a one liner

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