Shift positional parameters.
Syntax 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.
This is a BASH shell builtin, to display your local syntax from the bash prompt type: help shift
"Discovery consists of seeing what everybody has seen and thinking what nobody has thought” ~Albert Szent-Gyorgyi
Related macOS commands:
set - Set a shell variable = value