On Jul 22, 2011, at 11:34 AM, John Robinson wrote: > Lee says you don't really need to worry about repairing permissions and I > trust him completely.
Now that is an unwise thing to do. I don’t say that you should never repair permissions; I just say it's unlikely to cure problems. If it makes you feel better to repair permissions, then go ahead and do it. It probably won't hurt anything. It's certainly no more harmful than homeopathic medicine and might even be more efficacious. Here's why I think it's usually pretty useless. Whenever you install official Apple software using the Apple Installer or Software Update, the installation leaves behind a "bill of materials" (bom) file in /Library/Receipts. This file contains a list of permission settings for the newly installed files. These permissions are often set in a particular way for security reasons. When you repair permissions, the permissions are adjusted to be the same as in these lists. Repairing permissions doesn't fix things that aren't put there by Apple. Permissions don’t change spontaneously by themselves. If they are changing behind your back, then you're seeing a symptom of a different problem. Permission repair confuses a lot of people because they say "No matter how many times I repair permissions, it always finds errors!" This is because a file or directory may be listed with different permissions in two or more bom lists. A likely reason for this is that when Apple did a first upgrade, a permission was set wrong and then corrected in a later upgrade. Every time you run permissions, you'll see two errors for that file because it's set wrong in the older bom and then corrected in the newer bom. > I haven't defragmented a drive for years, TechTools Pro allows you to do so > but everything seems to run fine by updating the directory. Maybe it would > help but I have not taken the time, maybe someone else can better answer this. I haven't defragmented since before the turn of the century. Even way back when I usually avoided it because all that uber-intensive hunting, seeking and moving files around has always seemed to be a good way to create disk problems. Some people working with large video files say it's necessary. Since I don’t do such work, I don’t bother. My feeling is if you really need to defrag, then you need a bigger hard drive.
smime.p7s
Description: S/MIME cryptographic signature
_______________________________________________ MacGroup mailing list [email protected] http://www.math.louisville.edu/mailman/listinfo/macgroup
