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If (and only if) the variable is not set, prompt users and give them a default option already filled in.
The read command reads input and puts it into a variable. With -i you set an initial value. In this case I used a known environment variable.

Print unique ipaddresses as they come in from Apache Access Log File
Prints the unique IP Addresses as they arrive from an Apache `access.log` file. The '-W interactive' tells awk to start writing to stdout immediately and not buffer the output. This command builds on the uniq lines without sorting command (http://www.commandlinefu.com/commands/view/4389/remove-duplicate-entries-in-a-file-without-sorting.)

Generate Random Text based on Length

Convert a Nero Image File to ISO
This line removes the 300k header from a Nero image file converting it to ISO format

Find class in jar

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Display list of available printers

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.

List only locally modified files with CVS

Displays process tree of all running processes
G - uses VT100 line drawing a - shows command line arguments of process p - prints PID of process For other options, man pstree :)


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