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Double your disk read performance in a single command
(WARN) This will absolutely not work on all systems, unless you're running large, high speed, hardware RAID arrays. For example, systems using Dell PERC 5/i SAS/SATA arrays. If you have a hardware RAID array, try it. It certainly wont hurt. You may be can test the speed disk with some large file in your system, before and after using this: $ time dd if=/tmp/disk.iso of=/dev/null bs=256k To know the value of block device parameter known as readahead. $ blockdev --getra /dev/sdb And set the a value 1024, 2048, 4096, 8192, and maybe 16384... it really depends on the number of hard disks, their speed, your RAID controller, etc. (see sample)

convert filenames in current directory to lowercase
This will convert filenames from uppercase to lowercase. I find this useful after downloading images from my digital camera. This works for English, but other languages may need something slightly more complex like this: $ for i in *; do mv "$i" "$(echo $i|tr [:upper:] [:lower:])"; done Also, the quote marks aren't necessary if your filenames don't contain spaces.

SHA256 signature sum check of file
get the SHA256 sum signatur for a file

Print environment information.
Print environment (system) information using Perl.

Process command output line by line in a while loop
This snippet allows to process the output of any bash command line by line.

Send your svn diff to meld
If you like to view what has been changed between revision 100 and the BASE on FILE. Meld will give you a nice overview.

Check for Firewall Blockage.
This is just one method of checking to see if an IP is blocked via IP tables or CSF. Simple and to the point. Replace xx.xx.xx.xx with the IP you wish to check.

Set laptop display brightness
Run as root. Path may vary depending on laptop model and video card (this was tested on an Acer laptop with ATI HD3200 video). $ cat /proc/acpi/video/VGA/LCD/brightness to discover the possible values for your display.

Export unpushed files list

find geographical location of an ip address
a shorter version


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