Re: Read-only dir & files within?

Unix as designed and delivered has a fairly simple permission scheme. Later bolt-ons like SELinux (RedHat, Fedora, etc.) and Trusted Solaris add Access Control Lists similar to how OS/400 authorities backstop and override Unix permissions in the IFS, but that sort of thing is anything but universal.

The basic Unix scheme is:

1.
Roles:
*
user (owner)
*
group (group member)
*
other (public)
2.
Permissions
*
read (r)
*
write (w)
*
execute (x)

There are more "permission" bits that do things like "setuid" (adopt owner authority for an executable) and other fun stuff. Also you need "execute" permission on a directory to change directory ('cd') into it. https://www.redhat.com/sysadmin/linux-file-permissions-explained is a good learning path start.

The rule on IBM i is, if you can achieve what you want to achieve with the Unix permissions (and, implictly, the default Authorities hiding behind them in the LIC), then don't touch the Authorities side. It's true you can set these Unix permission bits in sort of screwy, "user friendly" combo ways using the Authorities interface [Your READONLY example earlier in the thread plays with the 'w' bits in the Unix permissions], but it if you really want to be clear what the heck it did to your perms on you have to use Unix commands to examine them anyway, so why bother with Authorities?

________________________________
From: MIDRANGE-L <midrange-l-bounces@xxxxxxxxxxxxxxxxxx> on behalf of Rob Berendt <robertowenberendt@xxxxxxxxx>
Sent: Thursday, April 4, 2024 8:32 AM
To: Midrange Systems Technical Discussion <midrange-l@xxxxxxxxxxxxxxxxxx>
Subject: Re: Read-only dir & files within?

I had to check the reference manual for chmod
I wasn't sure if you were trying to add Update+Write. But the manual said
that was adding Write to User.
Not intuitively obvious but looks like it would become second nature with
use.