The Perl Dr saw a function named Update::update and thought this was fine??
You need that second opinion!
There are a million kinds of updates out there. If I run across a function named update, I have no idea what it does, and I'll curse the person who wrote it with no mercy for the maintainance programmer looking for context.
Please name it something that gives a hint what it does. Something like "update_download" or "make_download_current".
While you're at it, I would leave out the superfluous "return 1". (Are you using that return anywhere?)