Repairing Permissions
Daring Fireball has a typically brilliant article on the voodoo cult surrounding ‘repair permissions’.
A phrase caught my eye — “Repairing permissions is zapping the PRAM for the twenty-first century” (from Rosyna via Jason Harris).
There was a step in between.
Prebinding.
There was a good 3+ year period where updating prebinding on the system was the cure-all for any kind of random system problem or slow down.
Somewhere in there, I made the “mistake” (it was actually a lot of fun) of releasing a little chunk of Cocoa code that demonstrated how to use the (then cool, no longer so) authorization APIs to run the prebinding update command and log the output into a text view.
From the start, it was documented as having the sole purpose of demonstrating a piece of API. That the actual act of updating prebinding was totally useless.
That didn’t stop anyone from downloading the damned up and running prebinding on a regular basis. I got email from people claiming that using Xoptimize (my stupid prebinding app) every week helped their system, that they had advised their mother to use it every day, and that — I’m not kidding — updating prebinding somehow made Finder window resizing faster.
That damned app had over 150,000 downloads. More than pretty much anything else except pyobjc. I almost wished I had charged money for it. Almost. It was useless and I have a hard time charging people for useless things (I’m trying to get over that).
Instead, I wrote an article that gave a high level overview of prebinding. Actually, a few people at Apple thanked me for doing so during the hiring process, so it wasn’t entirely for naught.
In any case, prebinding was definitely the voodoo fix-all between zapping pram and repairing permissions.


April 12th, 2006 at 11:05 am
Duck Prebind in the Twentieth and a Half Century, then?
April 12th, 2006 at 1:17 pm
I’m glad that people are starting to get wise that “Repair Permissions” is a useless superstition.
When I get ready to upgrade, I butter my nipples and I have never had any problems. So, don’t waste your time with the “repair permissions” hocus-pocus, but make sure you keep up with the nipple-buttering! That is science!
April 12th, 2006 at 2:35 pm
don’t forget deframentation. that’s another magical ritual that gets recommended by the fixit gurus out there.
April 12th, 2006 at 4:04 pm
MacFanDave: I find the butter trick works marvelously for me, but when I suggested it to a friend of mine, he frowned. You see, he’s a vegetarian, so nipple-buttering is strictly verboten. He claims that margarine works just as well and that he hasn’t had any troubles with it, but it might just be that he doesn’t know any butter.
April 12th, 2006 at 8:18 pm
Repair Permissions is not just superstition, but potentially harmful:
http://macenterprise.org/content/view/219/84/
April 13th, 2006 at 2:24 am
Now you tell me.
I’ve spent the last three years running Xoptimize every time before I checked for new mail. Actually, I ran both Xoptimize and Moo before each mail check – I think Moo was doing a better job, but I ran both just to be safe.
Even if you claim Xoptimize doesn’t work, I’d swear running Xoptimize and Moo really did speed up the mail checking process. I think I’ve saved quite a bit of time over the past few years.
April 13th, 2006 at 10:43 am
James: I think that is why most vegans use Linux. Updating Linux goes flawlessly when you sit in a shallow pan of warm tofu. Science!
April 13th, 2006 at 3:37 pm
Problem is Apple providing this feature in Disk Utility to begin with. It should have been
a background of installer or something like it. If the permissions are changing
by apps then there should be a log or something.
April 13th, 2006 at 3:41 pm
The “repair permissions” feature is quite useful. It just isn’t something that needs to be run before/after each and every installation.
April 13th, 2006 at 11:10 pm
Installer is the most likely time when Admin privileges is in play and files are copied
into system area. I don’t think the privileges are changing when app are running
unless they are asking for admin privileges. In Panther, I have run repair
privileges and gotten the same report so it is not changing fixing anything
which is quite frustrating. If it is so useful may apple should be telling the user
when to run it then there would not be any mystery involved. So if an experienced
user has hard time how is regular user going to cope with this.
April 14th, 2006 at 5:48 pm
Perhaps it’s time to go back to the recommendation of spreading chicken entrails across the keyboard before each upgrade.
April 15th, 2006 at 1:50 am
Repair Disk Permissions can’t die too soon. Same with the near half-century-old Unix-style permissions and their unscalable manageability on today’s large filesystems. It’s embarrassing to admit I was once a permissions pedant.
Oh, and manually deleting swapfiles from /var/vm is yet another frivolous maintenance ritual still performed by the underenlightened. A few system (over)maintenance utilities may still include that misfeature though I know at least one that it’s been thankfully removed from.