Jeff Johnson (My apps, PayPal.Me, Mastodon)

macOS: Attribute Not Found?

May 18 2023

I have a bit of a mystery, and I'm hoping that my readers can help me with it. When I was manually backing up my M1 MacBook Pro today, I experienced something bizarre that I can't explain.

Last year I wrote about my backup strategy for my new MacBook Pro. What I do is boot into recovery, mount the Data volume, and then run the following commands in Terminal:

pmset -a sleep 0

pmset -a disksleep 0

hdiutil create -encryption -format UDSB -srcfolder /Volumes/Data -noatomic -noscrub -volname 2023-5-18 -verbose -puppetstrings /Volumes/backup/2023-5-18.sparsebundle

(By the way, I've filed FB11120333 "hdiutil should prevent sleep".)

I've followed this routine weekly over the past year, and it worked every time. Today, however, I ran into an error: "Attribute Not Found". This happened on every attempt, a few seconds after starting hdiutil. The error happened with the same file every time. The file path had this format:


There are a bunch of these text files inside the Spotlight store, and they appear to contain imported Spotlight data. In Terminal, I tried to cat the file in question, but I couldn't! I got the same "Attribute Not Found" error from the cat command.

I believe the error is actually kPOSIXErrorENOATTR. As you can see, Apple's "documentation" is not helpful, nearly nonexistent. If you're wondering, the files don't appear to have any xattr.

I supposed that it must have been some kind of file corruption. I tried to repair the volume in Disk Utility, but that didn't change anything, or show any errors. Since I really needed to back up the disk before I installed the macOS 12.6.6 update (I was running 12.6.5), and I was at a loss about what else to do, I decided to just rm the file. This worked, no error. For good measure, I also rmdir the containing directory, which was otherwise empty. And afterward, hdiutil was able to complete its backup job successfully! I've installed 12.6.6, and I'm not experiencing any problems now as far as I can tell. Yet the mystery remains, and now I fear that the problem may happen again in the future.

Does anyone know what that "Attribute Not Found" error was about? If you have any experience with this, please let me know. My contact info is on my main page. Thanks! I'm puzzled.

Jeff Johnson (My apps, PayPal.Me, Mastodon)