How to inspect and change them, in the Finder and the command line.
permissions
When I try to move files onto my hard drive, I have to authenticate. How can I fix this?
When an app ran fine, but crashes in El Capitan, it may be SIP’s fault. Here is how to check, and more about SIP.
When copying files across in Target mode, their permissions are left in a mess. Why?
How did some of my old disks and folders get to have ‘custom access’, and how can I fix that?
Using TinkerTool System or MacPilot to make easier use of the Shared folder using ACLs.
Disk Utility warns of SUID files and ACLs. How can I complete repairing permissions?
When I put an item into the Trash, my external drive only offers to delete it immediately. Why is that?
Since migrating to a new iMac I have had problems accessing some of the images on an external drive. How can I repair its permissions?
You can use ACLs to ensure that all files created in a shared folder inherit the permissions of their parent folder.
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