http://www.perlmonks.org?node_id=1009770


in reply to Running rpsblast on all files in directory, using perl

Given that your error msg mentions arguments starting with a dash and you precede argument d with an endash or emdash, I'd start by replacing it with a regular dash. Compare the following (not sure how they will turn out on your screen, but here are dash/endash/emdash): -d/–d/—d