Unable to write to /tmp directory in macOS, unable to correct permissions: “Operation not permitted”

macOS El Capitan (10.11) is unable to install any software updates or install any software because the /tmp and the /private/tmp folders don't seem to be writeable.

Running this:

sudo /usr/libexec/repair_packages --repair --standard-pkgs --volume /

Gives me this error:

unable to set owner and group on "tmp" Error 1 Operation not permitted
unable to set permissions on "tmp" Error 1 Operation not permitted

Is there a way to manually delete the tmp folders and recreate them? When I tried renaming or deleting /tmp or /private/tmp I kept getting operation not permitted. sudo chmod 1777 also failed in the same way on both /tmp and /private/tmp folders

Disk Utility says the disk is healthy with no issues detected when running first aid.

Is there any way to redirect the tmp location to another writeable folder?

Answer

1. Reboot your Mac into recovery mode


2. 
   

   Open Utilities menu in the top bar > open Terminal

   
   

   csrutil disable
   



3. 
   

   Reboot

   
   


4. 
   

   Remove the tmp folder

   
   

   sudo rm -i /tmp
   sudo rm -i /private/tmp
   



5. 
   

   Create tmp folder

   
   

   sudo mkdir /private/tmp
   sudo chown root:wheel /private/tmp
   sudo chmod 1777 /private/tmp
   



6. 
   

   Create the symlink

   
   

   sudo ln -s /private/tmp /tmp
   



7. 
   

   Run repair_packages (you may not need to do this)

   
   

   sudo /usr/libexec/repair_packages --repair --standard-pkgs --volume /
   



8. 
   

   Reboot back to recovery mode and run

   
   

   csrutil enable
   



9. 
   

   Reboot

   
   

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Props to Andrew Ferk for figuring out a fix; pulling out your comment as a community wiki answer so it's more readable.