$ perl -MData::Dumper -MGetopt::Long -e'
   my %options = ( input => [] );
   GetOptions(\%options, "input=s{0,}", "des=s", "r=i")
      or die;
   print(Dumper(\%options));
' -- -input data modem apps -des "finding files" -r 1000
$VAR1 = {
          'r' => 1000,
          'input' => [
                       'data',
                       'modem',
                       'apps'
                     ],
          'des' => 'finding files'
        };