ABOUT shift
shift [n] The positional parameters from n+1 ... are renamed to $1 .... Parameters represented by the numbers $# down to $#-n+1 are unset. n must be a non-negative number less than or equal to $#. If n is 0, no parameters are changed. If n is not given, it is assumed to be 1. If n is greater than $#, the positional parameters are not changed. The return status is greater than zero if n is greater than $# or less than zero; otherwise 0.
[bash]
$cat posiwork
shift
echo $1
$./posiwork hello world
world
$./posiwork hello
$./posiwork hello world people
world
$emacs posiwork
$cat posiwork
shift 2
echo $1
$./posiwork hello world people
people
$
[/bash]
LINKS
https://askubuntu.com/questions/939620/what-does-mean-in-bash
https://www.computerhope.com/unix/bash/shift.htm
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