# Functional style use Digest::HMAC_MD5 qw(hmac_md5 hmac_md5_hex); $digest = hmac_md5($data, $key); print hmac_md5_hex($data, $key); # OO style use Digest::HMAC_MD5; $hmac = Digest::HMAC_MD5->new($key); $hmac->add($data); $hmac->addfile(*FILE); $digest = $hmac->digest; $digest = $hmac->hexdigest; $digest = $hmac->b64digest;