if ( !$self->{use_threads} ) {
   my $_wid  = $_args[1];
   my $_seed = abs($self->{_seed} - ($_wid * 100000)) % 2147483560;

   CORE::srand($_seed);

   # PDL 2.062 ~ 2.089
   PDL::srand($_seed) if $INC{'PDL.pm'} && PDL->can('srand');

   # PDL 2.089_01+
   PDL::srandom($_seed) if $INC{'PDL.pm'} && PDL->can('srandom');

   ...
}