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  • Living with Leopard: Book VIII — The Great Data Loss Controversy

    November 7th, 2007

    The worst thing a personal computer operating system can do, aside from crashing a lot, is to destroy your data. Indeed, a bug of this sort ought to be a show-stopper, but if you believe all those lurid headlines, such a defect was allowed to remain in Leopard when it was released.

    If it sounds frightening to you, you aren’t alone. Certainly, if true, Apple ought to be working like crazy to find a solution, and get it released as soon as possible.

    But is this all some new and dreaded defect, or something that’s been a part of the Finder for a while? What’s more, what must you actually do to send your data into oblivion?

    Now I wouldn’t recommend that you try this at all, but all you have to do is use a standard Mac OS shortcut for moving files from one drive or partition to another, while deleting the original file. To perform this action, simply hold down the Command key when you drag the file to its new location.

    This would seem to be a particularly benign action, and I have little doubt that it works precisely as advertised 99.99% of the time. But what if something happens to interrupt the file transfer, such as a power outage during a thunderstorm, a file share disconnecting from the network, or the target drive crashes?

    Well, in theory, the Finder ought to keep the original file intact until the file system confirms that the item has been successfully moved to its new location intact. In fact, that’s how it apparently works on the Windows platform.

    However, theories don’t always succeed in the real world. In this case, if something happens to the file on its way to another drive, the original is deleted anyway. So you’re left with a corrupted copy, or perhaps nothing at all!

    Indeed, this is a dangerous bug, but it may not be a Leopard-specific defect after all. There are already widespread reports — with apparently enough testing involved — to confirm that this file move issue goes way back to Tiger and perhaps even to Panther. Other reports, which may have less authenticity behind them, trace this particular problem way back to Mac OS 9.

    For some reason, it wasn’t discovered or at least confirmed until now, although I fail to see why.

    Indeed, wouldn’t it appear at times during Apple’s quality control testing, or was it mistakenly buried in an online bug report, and somehow overlooked? Could it be that it only happens occasionally, even when the proper conditions are reproduced? If that’s the case, it would make it doubly difficult to solve.

    I can’t pretend to know what has been going on behind the scenes, only that I would hope that, with the renewed attention to this apparently serious defect, however long it has persisted, it will soon be eradicated. And, no, I am not going to accept those unconfirmed reports that Apple is already testing a Leopard update that contains this fix. Even if true, we don’t know when the rumored 10.5.1 will be out, or what fixes will survive the testing process.

    In the meantime, despite the fear-mongering on the part of some members of the tech and mainstream press, none of this should deter you from installing Leopard, assuming the applications you use are compatible. I have gone out on the limb in saying that my particular upgrades — and those performed by people I know — have been universally successful in every respect.

    Of course, I use an awful lot of applications, and I’ve found some instances of weirdness here and there, but nothing I couldn’t work around rather easily. The key here is the stability and speed of your workflow. If there’s something in Leopard, or a third-party application, that will cause problems with either or both, then I would suggest you hold off installing Leopard for now and wait for some further updates.

    Over the next few weeks, however, you will be hearing more and more about the alleged show-stopping problems in Leopard. Some of that information will no doubt be true. As more and more of you install Mac OS 10.5, you will possibly experience anomalies that Apple couldn’t predict or expect.

    It may also be true, as some suggested, that Leopard was forced out of the door prematurely by Apple’s marketing, knowing they had to make good on their promise to deliver the goods before the end of October. One clue that this sort of speculation might be correct is the fact that Leopard went on sale officially almost at the last minute, far closer to the scheduled release date than you might expect.

    Perhaps, as some suggest, Apple struggled as hard as it could against its self-imposed deadline to deliver a build of reasonable quality and then declared it Golden Master, knowing full way some features, such as, perhaps, the firewall and a few others, were a little half-baked. In the end, it’s all about money, and you shouldn’t expect Apple to behave any differently.

    Meantime, if you’re concerned about suffering data corruption or loss from that apparent Finder bug, take the advice of the doctor in that very old vaudeville joke:

    The man says: “Doctor, it hurts when I do that.”

    The doctor responds: “Don’t do that!”

    In other words, don’t use the Finder’s move command to send a file to another drive. Just drag it over, and when the copying process is done — and only when that’s confirmed — delete the original manually.



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    6 Responses to “Living with Leopard: Book VIII — The Great Data Loss Controversy”

    1. Ken says:

      Yes, Apple should fix it quickly, but as a Mac user since 1988, I never even noticed the “move” function. I have always used copy and then delete. It never occured to me to do it any differently.

      The first time I ever saw “move” was on a Windows machine, so it makes me wonder if “switchers” are the ones who have the problem since they tend to try to do things the Windows way even after switching.

    2. Tom says:

      I’ve been a mac user for 17 years and though I know you can use the move command, I’d never recommend it on anything other than small files. Furthermore, as an experienced Windows admin, I can tell you that Windows certainly suffers from the same “problem”.

      Don’t use the move function with anything you highly value, and never over a network connection. Whether it’s Mac or PC, you’ll regret it if you even get a network hic-up, much less a power loss. It’s just as easy to copy and delete.

    3. I’ve been a mac user for 17 years and though I know you can use the move command, I’d never recommend it on anything other than small files. Furthermore, as an experienced Windows admin, I can tell you that Windows certainly suffers from the same “problem”.

      Don’t use the move function with anything you highly value, and never over a network connection. Whether it’s Mac or PC, you’ll regret it if you even get a network hic-up, much less a power loss. It’s just as easy to copy and delete.

      Thanks for the enlightenment.

      The only thing that concerns me is the claim this is a long-standing bug, and why there haven’t been widespread complaints up till now. All this is being used as ammunition for the “Leopard is a mess” brigade.

      Peace,
      Gene

    4. Tom B says:

      It’s a serious bug, but it only comes into play when the User deliberately by-passes a fail safe to save time. Also, I would anticipate that it would be pretty easy for Apple programmers to fix. One could almost make an Applescript that would fix the problem.

    5. It’s a serious bug, but it only comes into play when the User deliberately by-passes a fail safe to save time. Also, I would anticipate that it would be pretty easy for Apple programmers to fix. One could almost make an Applescript that would fix the problem.

      I would presume that a properly-designed system of this sort would allow for integrity-checking, to make sure that a moved file has copied successfully before the original is deleted. I suppose that’s where this setup is failing, that the file system isn’t reporting the situation accurately. Oh well, we’ll see how it all plays out.

      Peace,
      Gene

    6. jamess says:

      Hi,

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