As I related, I have recovered the data from a MacBook Pro that quit working on me a couple of weeks ago, and that I used the ditto command to do it. For the benefit of those more savvy Macheads among my honored readers, I’ll offer a few more details on the process and its outcome.When I discovered that Disk Utility would not create a restorable image of the dead MacBook Pro’s internal drive, I fell back to ditto, figuring that to populate the new MacBook Pro with my existing data, I’d have to resort to a cautious, manual transfer to a clean Tiger install of those documents, applications and preferences that I could safely overwrite. I knew that some information that was encoded in binary form would have to be recreated in the application or preference pane that produced it, and that I’d lose the benefit of Migration Assistant’s automated upgrade to Leopard.As it turns out, Migration Assistant transfers files without much concern about the validity of their contents except when data translation is part of the process. When I finished with ditto, I had an OS X Tiger partition that I knew wasn’t worth finessing into a bootable state. It might be worthwhile as the source for a Leopard Migration Assistant run. It was, and the result was better than I could have hoped. Most 3rd-party kernel extensions didn’t survive the trip, but this gave Migration Assistant no trouble.The sole losses were kernel extensions and license managers and keys. The lesson here is that a restorable block-by-block partition image need not be your objective in backing up or recovering data. It is okay to write changes to files as they are modified, just as Time Machine does. Time machine can even be outdone by ZFS and overlay mounts.Whatever you do to back up your data to an external hard drive, don’t use USB. Buy enclosures that have USB and FireWire. Software Development