$start = $ARGV[0];

if ($start eq '') {
    $start = &get_start_level;
}
sub get_start_level {
    print "Please Enter the Start-Level (0-7,?)[0]: ";	
    $input = <>;
    # clear all but numbers or '?'
    #if ($input ne '?') {
    #	$input =~ tr/!(0-9)//\d;
    #}
	
    if ($input eq '?') {
  	print " **** internally coded help information  **** \n";
	print " **** internally coded help information  **** \n";
	$input = &get_start_level;
    } elsif (($input < 0) || ($input > 7)) {
	print "please enter a number that is between Zero and Seven\n";
	$input = &get_start_level; 
    }
    return ($input);
}
  =========================== end code  ============