Commands by The_IceMan_Blog (2)

  • Remove all older kernels then the current running kernel for Ubuntu/Debian base system


    0
    export KEEP_KERNEL=2; dpkg -l 'linux-image*' | awk '/^ii/ { print $2 }' | grep "[0-9]" | awk 'BEGIN{i=1}{print i++, $0}' | grep `uname -r` -B99 | sort -r | tail -n+$(($KEEP_KERNEL+2)) | awk '{print $2}'| xargs apt-get -y purge
    The_IceMan_Blog · 2013-11-23 15:35:42 7
  • Check if you partition are aligned

    To get most of you HDD/SSD driver you need to make sure you partition are aligned, if not the speed penalty can be up to 50% slower! this simple one liner will check to see if each partition start sector is divided by 512 you need to change sda with your driver if you find the one of your partitions is not aligned use gparted to move the start sector of the partition to be divided of 512 Show Sample Output


    1
    fdisk -l /dev/sda | grep -E sda[0-9]+ | sed s/*// | awk '{printf ("%s %f ",$1,$2/512); if($2%512){ print "BAD" }else {print "Good"} }' | column -t
    The_IceMan_Blog · 2012-05-18 08:34:36 5

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Another way of doing it that's a bit clearer. I'm a fan of readable code.

Delete Last Line of a File if it is Blank
Use sed to remove the last line of a file only if it is empty.

Show current pathname in title of terminal
This helps to keep track of what is going on when you have several tabs open in your terminal. The title automatically changes when you change directories.

Sorted, recursive long file listing
Tells you everything you could ever want to know about all files and subdirectories. Great for package creators. Totally secure too. On my Slackware box, this gets set upon login: $ LS_OPTIONS='-F -b -T 0 --color=auto' and $ alias ls='/bin/ls $LS_OPTIONS' which works great.

ls -hog --> a more compact ls -l
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pretend to be busy in office to enjoy a cup of coffee
The first parameter after timeout is the key parameter; number of seconds to wait. With a 6 you have 600 seconds for your coffee break (10min).

Find recursively, from current directory down, files and directories whose names contain single or multiple whitespaces and replace each such occurrence with a single underscore.
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Show me a histogram of the busiest minutes in a log file:
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Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Screencast with ffmpeg x11grab
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