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 "$1";}
    totti · 2011-07-29 13:04:19 4
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Audible warning when a downloading is finished
This command can be set as an alias in ~/.bashrc For example (in my case) I have : alias watchDl='while [ "$(ls $filePart)" != "" ]; do sleep 5; done; mpg123 /home/.../warning.mp3" ' Then I just need to - initialize filePart (e.g. filePart="*bigFile*rar.part") - launch watchDl

In (any) vi, add a keystroke to format the current paragraph.
That goes into your $HOME/.exrc file. " Nice macro to reformat lines: map ^A !}fmt Note that the ^A has to be input by typing ^V^A.

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" }

Renaming a file without overwiting an existing file name
Sometimes in a hurry you may move or copy a file using an already existent file name. If you aliased the cp and mv command with the -i option you are prompted for a confirmation before overwriting but if your aliases aren't there you will loose the target file! The -b option will force the mv command to check if the destination file already exists and if it is already there a backup copy with an ending ~ is created.

check open ports without netstat or lsof

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Create a bunch of dummy files for testing
Sometimes I need to create a directory of files to operate on to test out some commandlinefu I am cooking up. The main thing is the range ({1..N}) expansion.

Convert a bunch of HTML files from ISO-8859-1 to UTF-8 file encoding in a folder and all sub-folders
This is my first attempt at converting all HTML files to UTF-8 file encoding, including all subfolders. Theres probably a much more compact way to do it, but I'm quite proud of it with my windows background ;)

Ping all hosts on 192.168.1.0/24

Lines per second in a log file
Another way of counting the line output of tail over 10s not requiring pv. Cut to have the average per second rate : tail -n0 -f access.log>/tmp/tmp.log & sleep 10; kill $! ; wc -l /tmp/tmp.log | cut -c-2 You can also enclose it in a loop and send stderr to /dev/null : while true; do tail -n0 -f access.log>/tmp/tmp.log & sleep 2; kill $! ; wc -l /tmp/tmp.log | cut -c-2; done 2>/dev/null

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