How to read command line arguments in a bash script

To input arguments into a Bash script, like any normal command line program, there are special variables set aside for this.

The arguments are stored in variables with a number in the order of the argument starting at 1
 * First Argument: $1
 * Second Argument: $2
 * Third Argument: $3


 * Example
 * command: ./script.bash alpha beta gamma
 * Variables: $1=='alpha'; $2=='beta'; $3=='gamma'

The variable $0 is the script's name. ''The total number of arguments is stored in $#. The variables $@ (array) and $* (string) return all the arguments.''

For more complicated examples, you might consider getopt: http://aplawrence.com/Unix/getopts.html

=Script Example= echo "the $1 eats a $2 every time there is a $3" echo "bye:-)"
 * 1) !/bin/bash

=See Also=
 * Command: ./script.bash dog bone moose
 * Output:
 * the dog eats a bone every time there is a moose
 * bye:-)
 * Bash
 * shell script
 * Howto read command-line arguments in a perl script

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