print "Copying $src_path\\$upc\\$tracknum.mp3 to $dst_path\\$upc\\$tracknum.mp3\n";
copy("$src_path\\$upc\\$tracknum.mp3","$dst_path\\$upc\\$tracknum.mp3") or
  warn "Couldn't copy $src_path\\$upc\\$realtracknum.mp3: $!";