disk device permission reverting after chmod?

abolishtheun · 06-28-2009, 04:27 AM

Why does /dev/sdc's permission keep reverting to 660 when I explicitely chmod it 664? It seems to happen as soon as I touch it. It's got to be some security feature... distro is ubuntu 9.04

Code:

user@user-desktop:~$ ls -l /dev/sdc
brw-rw---- 1 root disk 8, 32 2009-06-28 02:18 /dev/sdc

user@user-desktop:~$ sudo chmod 666 /dev/sdc
[sudo] password for user: 

user@user-desktop:~$ ls -l /dev/sdc
brw-rw-rw- 1 root disk 8, 32 2009-06-28 02:18 /dev/sdc

user@user-desktop:~$ touch /dev/sdc

user@user-desktop:~$ ls -l /dev/sdc
brw-rw---- 1 root disk 8, 32 2009-06-28 02:23 /dev/sdc

jiatong · 06-28-2009, 06:24 AM

what file system are you using? Perhaps you are trying to change the permissions of a file system (like most of the windows ones) which does not support linux type permissions.

EDIT: nvm just realized your trying to set the permissions of a device node not a file on another disk/partition itself