Further to my question about the "." at the end of the permissions I saw on a file:On Oracle Linux 8.10 (minimal install, anyway) there is no "lsattr" command. Also, the file system is xfs and I think lsattr doesn't work on xfs.
At any rate, I was able to install the "attr" command which supports xfs. I got this result:
[root@cowsvtora810 ~]# cd /etc/sudoers.d
[root@cowsvtora810 sudoers.d]# ls -l
total 12
-r--r-----. 1 root root 26 Mar 3 02:56 ansible
-r--r-----. 1 root root 25 Mar 3 02:56 packer
-r--r----- 1 root root 26 Mar 3 16:54 systems
[root@cowsvtora810 sudoers.d]# attr -l ansible
Attribute "selinux" has a 31 byte value for ansible
[root@cowsvtora810 sudoers.d]# attr -l packer
Attribute "selinux" has a 27 byte value for packer
[root@cowsvtora810 sudoers.d]# attr -l systems
[root@cowsvtora810 sudoers.d]# attr -g selinux packer
attr_get: No data available
Could not get "selinux" for packer
[root@cowsvtora810 sudoers.d]# getfattr --name selinux packer
packer: selinux: Operation not supported
[root@cowsvtora810 sudoers.d]# getfattr --name root.selinux packer
packer: root.selinux: Operation not supported
That's probably sufficient to answer my question. There are additional attributes and they relate to selinux. I don't need to pursue this any further than that, although if anyone knows what the 31- and 27-byte attribute values might be, I'm curious.