In our the previous post we written about dot at the end of permissions this is one more special permissions where you will find + at the end of permissions field in ls -l command output.

This is actually a small post, which is asked by one of the requester. This is a special permission in Linux which indicates that ACL(Access Control List) is implemented on that file/folder. Some times you will be seeing +(Plus) at the trailing end of permissions


ls -l tempfile

drwxr-xr-x+ 3 user1 user1 4096 2011-07-06 00:19 tempfile
If you observe you will find 11th character to the initial 10 characters permission field available in Linux. The plus sign is an indication of ACL (access control list) which is an extension to the normal POSIX permissions system which increases security by allowing the system more fine-tuning to a access for a file/folder in system. The ACL’s can be implemented using setfacl command, we will see about ACL in our coming posts. Please tune in for more stuff on this Permissions.

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