BSD grep vs GNU grep has burned me enough times that when I do anything moderately complex in a bash script, I quickly move to Perl. And since Perl is installed

BSD grep vs GNU grep has burned me enough times that when I do anything moderately complex in a bash script, I quickly move to Perl. And since Perl is installed most everywhere (or can be bundled up easily with PAR::Packer), it's an easy decision for me.