shift [n] The positional parameters from n+1 ... are renamed to $1 .... Param- eters 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. Shift is an command it transfers the contents of a positional parameters to its immediate lower numbered one this is done as many times as the statement is called