[HrDe]

can you explain it more detail? i mean, in every command: what's -r and what's -c does?

-r used for restart if we want system to shutdown then we write -s and also used -f for force fully shutdown means all open program close force fully and system go to shutdown.
-c used for display your msg at time shutdown.

i think it's help full for u,if any question then reply me.
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