Mac Forum / General / General / May 2008

The log shows that Repair Permissions first read a receipt that
indicates /Private (no idea why the first is capitalized) should be
owned by group "admin" (80) and should allow group write access. The
folder is not owned by group "admin" and does not allow group write
access, so it corrects that. Then, Repair Permissions read another
receipt that indicates /private should be owned by group "wheel" (0) and
should *not* allow group write access, so it correct that. This will
continue each time you run Repair Permissions until the offending
receipt(s) are removed or changed.

It's important to understand how repair permissions works. It reads
everything in /Library/Receipts to find out which files and folders it
should examine. Each receipt in that folder describes the ownership and
permissions the files and folders listed in that receipt should have. If
there happen to be multiple receipts that list /private, and the
ownership and permissions differ between those two receipts, the Repair
Permissions function will encounter the first receipt, change the
ownership and permissions to reflect that receipt, then encounter the
second receipt and change the ownership and permissions to match the
second receipt.

Repair Permissions isn't the magical tool most Mac users think it is.
It's a rather brain-dead tool that is meant to repair ownership and
permissions of specific sets of files, and only those files listed in
the receipts of specific software in the /Library/Receipts folder. And,
as you can see, the tool has a rather serious flaw, in that it does not
know how to resolve the case where multiple receipts list the same file
or folder with differing ownership and permissions. I wish more people
understood this - we probably wouldn't find so many Mac users running
Repair Permissions at the drop of the hat or on a regular schedule as we
see so often.  ; )

IMO, if you are not experiencing problems with a piece of software
listed in the /Library/Receipts folder, there's no reason to run Repair
Permissions.

If you want to fix this problem on your machine, you'll need to figure
out which receipt in /Library/Receipts mentions /Private, and which
receipt mentions /private, then decide whether you believe /private
should be owned by group "wheel" or "admin", and whether group should
have write access, and finally change the receipts appropriately (or
delete the offending receipt).

I can tell you on my 10.5 install, /private is owned by group "wheel"
and does *not* give group write access:

drwxr-xr-x@   7 root   wheel   238B Nov  6  2007 private