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navit
30th October 2004, 01:32 PM
If a superuser runs an appliaction in unix does it mean it's runs in priviledged mode?
and i realy need an explanation not just yes/no

kosmosik
30th October 2004, 01:40 PM
superuser means root. root means user ID (UID) = 0... proceses in UNIX/Linux are run with UID's meaning process started by user joe with UID 1002 will run as user joe (UID 1002)... now process started as root (UID 0) will probably run as root - with super user powers and full access to everything (assuming you are not using some MAC but plain old cheesy unix privilege scheme). than yes. it may run as user root. but not must - some programs are run as root but then drop their privileges to different account (but only root process can change it privileges).

ilja
30th October 2004, 01:41 PM
Yes, the applications that are startred by an user run with his rights. So for the root (superuser) this means that it has privileged rights.
With Setuid and sudo it is possible to write programms with foreign rights.

navit
31st October 2004, 07:08 PM
I ment if it runs in kernel mode?

kosmosik
31st October 2004, 07:24 PM
no it runs in user mode... kernel and kernel modules work in kernel space, everything else works in user space...

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