Making Hard Sector Floppies

On Wed, 31 Mar 2010, E. Groenenberg wrote: There are vintage lasers. And it would be far from the first vintage computer use of a laser. Remember Vault Corp. "Pro-Lock"? They created a copy-protection scheme based upon making and looking for a physical scratch in the disk surface. As a second stage, if their software could successfully re-write at the location of the scratch, then it knew that the disk was bogus. But, Vulture Capitalists would not be attracted to a workroom with a bunch of workers with paperclips scratching disks. So, to make the scratch, they used a "laser fingerprint"! Later, they did one of the most spectacular foot shootings, ever! They announced that "Pro-Lock 2" would retaliate against computers using bogus copies! ("with a VIRUS!!") As far as I know, they never sold a single copy of "Pro-Lock 2", and EVERY customer of "Pro-Lock 1" discontinued immmediately; many with public announcements. For years, the least informed Q&A people in magazines would blame problems that they didn't understand on "maybe a virus, or maybe a copy-protection program that went bad". -- Grumpy Ol' Fred cisin at xenosoft.com