Getting to grips with Linux Permissions

DO IT WITH PERMISSION

Author(s):

From the vault:This article first appeared in issue #1 (October 2000). You'll also find this article on our 10-year anniversary Archive DVD included in issue #120 (November 2010).

With any operating system it is important to ensure that users remain in control of their files and directories and are prevented from tampering with those belonging to other users, or the system. This is what the Linux permissions system is all about, as Jono Bacon explains.

The 10-year anniversary issue hits newsstands starting:
Europe: October 4
North America: October 29
Australia: November 29
[flickr image courtesy of jessica.diamond]

Permissions are at the heart of how Linux works. Some operating systems (such as MS-DOS and some variants of Microsoft Windows) treat all files in the same way. This means that any user can change any file. Usually, there is only one kind of user.