[<<]Message[>>] [<<]Author[>>] [<<]Subject[>>] [<<]Thread
Number : 3446 Date : 2003-01-05 Author : Kan Yabumoto Subject : Re: How to schedule an XXCOPY run Size(KB) : 3
Why there is no "undo" switch? In one sense, backing up your files is a good (and most versatile) way to undo anything. It won't be as automatic as you may wish. But, it sure is flexible. And, XXCOPY provides many different ways to backup your file. It is all up to the user to design his favorite way to undo things. People often asks us for a feature immediately after a mistake is made --- at the moment, the most important undo feature is the one that would fix the kind of mistake that was just made. But, if we generalize the undo capability to its ultimate end, it really boils down to a complete backup operation. Even the backup operation can be of many different forms. We often make a daily backup. I think daily backup is just about a very convenient and good interval. Some xxcopy users perform hourly backups. In some extreme cases, people run backup in every 10 minutes. There is no one magic backup interval that works best in all cases. The best way is to multiple interval multiple-sets of backups. 10-minute backup hourly backup daily backup weekly backup Why do we want so many variations? After all most of these are redundant. Yes, that's true. But, it all depends on how far backup you may want to go back. Remember, if the interval is very short, a corrupted data will also be propagated after a short period. If you make a mistake in editing an important file (without keeping its previous version as a backup or separate file), and if you don't realize that you made a mistake for three hours, then, both the 10-minute backup and hourly backup are both useless. The good version was already replaced by the newer and bad one by the hourly backup or the shorter-interval backup. That is why sometime a weekly backup saves your life. If you don't realize the mistake you made today by the end of the day (often, the daily backup is done while you are asleep), it will be too late when you find that out first thing in the morning next day. The daily backup will faithfully replace yesterday's good file by today's one with mistakes. Going back to the undo feature. How many levels of undo do you want? If XXCOPY allows you to undo just the most recent operation and nothing else, I'm sure many users will wish such a restriction removed. Why? Because, unless you are extremely alert, you may run a few XXCOPY operations before you realize a mistake was made a few steps earlier. So, one-step undo is probably too limited. Probably, it would be more useful if you can undo within a few hours or a few days. Or, you may set aside some storage space (measured by a quota in GB). Then, you may wish to prevent some few huge files to wipe out many small files ---- I rather lose one huge files than hundreds of small files, but it is really hard to say). Then, we are talking about the same problem of the "different strokes for different folks" syndrome. When we implement just one very elaborate scheme of the undo operation, and also implements "the ultimate method (--- fool proof, of course) of backup scheme, such a tool will become monstrously difficult to use for most users. At the very least, people start hating XXCOPY for its arrogant design which imposes complex rules when a desirable feature (such as undo and backup) is provided in only one way. So, for now (until we get really arrogant), you should think about safety features when building your batch file (not an XXCOPY built-in safety feature, but your clever scheme to write a robust script which prevents a disaster. A few hours ago, I was doing some picture editing using Windows' Paint program. It has an undo feature. But, I was quite frustrated that the undo did not go back far enough to really undo what I did (which was counted as too many steps by the program). Kan Yabumoto
This message if part of XXCOPY's message Archive. The archive contains all the messages posted at Yahoo!Groups: XXCOPY.