Quick Start Guide

on the primary group the user belongs to when creating the object. When you create
a new le or directory, initial access permissions for this object are set according to
a predened scheme. For further details refer to Section 17.5, “File Access Permis-
sions” (page 200).
As the owner of a le or directory (and, of course, as root), you can change the access
permissions to this object.
To change object attributes like access permissions of a le or folder, use the chmod
command followed by the following parameters:
• the users for which to change the permissions,
• the type of access permission you want to remove, set or add and
• the les or folders for which you want to change permissions separated by
spaces.
The users for which you can change le access permissions fall into the following
categories: the owner of the le (user, u), the group that own the le (group, g) and
the other users (others, o). You can add, remove or set one or more of the following
permissions: read, write or execute.
As root, you can also change the ownership of a le: with the command chown
(change owner) you can transfer ownership to a new user.
17.5.3.1 Examples for Changing Access Permissions and Ownership
The following example shows the output of an ls -l command in a shell.
Example 17.2: Access Permissions For Files and Folders
-rw-r----- 1 tux users 0 2006-06-23 16:08 checklist.txt
-rw-r--r-- 1 tux users 53279 2006-06-21 13:16 gnome_quick.xml
-rw-rw---- 1 tux users 0 2006-06-23 16:08 index.htm
-rw-r--r-- 1 tux users 70733 2006-06-21 09:35 kde-start.xml
-rw-r--r-- 1 tux users 47896 2006-06-21 09:46 kde_quick.xml
drwxr-xr-x 2 tux users 48 2006-06-23 16:09 local
-r-xr-xr-x 1 tux users 624398 2006-06-23 15:43 tux.jpg
In the example above, user tux owns the le kde-start.xml and has read and write
access to the le but cannot execute it. The users group can read the le but cannot
write or execute it. The same holds true for the other users as shown by the third
block of characters.
Procedure 17.4: Changing Access Permissions
Suppose you are tux and want to modify the access permissions to your les:
1
If you want to grant the users group also write access to kde-start.xml, enter
chmod g+w kde-start.xml
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