This still doesn't make sense to me. What pack("u") does is take _binary_ data and encode it as _ASCII_ data so that it can be sent through ASCII-only transport media (such as 7-bit SMTP). You are taking ASCII data and uuencoding it. This accomplishes nothing but making it 33% longer and hard to read.

When you do an unpack "u", you are only going to get _one_ string out. If you print $dataU[0]; you will see that it contains all the lines from your original file concatenated, with newlines still included.

You still haven't explained why you want binary. What do you think the advantage is?