Positional parameters are used to access the command-line arguments. These are the trailing words that come after the command line call.
$ myShellScript posParam1 posParam2 posParam3
The first argument is denoted by
$1, the second by
$2, and so on. Any two-digit values are to be wrapped around in braces such as
$0 variable is the name of the command itself. This can be useful when printing out error messages.
If the user does not input any arguments, but you still call a positional parameter, then the shell takes it in as
shift command is used to shift the arguments over one. This removes the first argument, and advances the rest of the input arguments forward. We'll revisit this when using loops, where this command can be useful.
Here is a list of other important parameters.
shiftvariable within a loop.
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