cp -u and filesystems

The otherwise excellent cp -u variant is no good for copying between ext3 and fat32 filesystems - fat32 records last modification times to the nearest 2 seconds (just like MS-DOS!) and ext3 is much more accurate. So very often cp -u will wish to make an unnecessary copy from ext3 to fat32, and fail to suggest a necessary copy from fat32 to ext3.

There used to be a page at http://vb.mvps.org/hardcore/html/filedatestimes.htm explaining that there's even more bizarreness to the FAT32 date situation than I mention here, but it's been replaced by one of those smart-arse 404 messages, so fuck them.