I don't know a lot about the DOC format, but I'm pretty sure it's a binary format. It's probably not a good idea to insert extra newlines into it, as you're doing here. Just read and print the lines, without changing anything, if that's your goal. (Of course, if that's your goal, why not just use the filesystem copy command?)

Also, you're appending to the output file. If it doesn't exist, it'll be created, and that'll be fine. But if it does exist, and you're really appending to it, the DOC format may not appreciate that either.