4.
4. naldo11. - Maintaining2. Booting3. - Shutting down4. proc 5. Managing User Accounts2 Root root . ,
Ex) rm rf / : init 1 : 1 . , . . rm rf command , . init1 1 . .
, , , , . , , . , , .
.4 , root
root .
. , . root , .5su & sudo su (substitute user) : ID . root . exit .
su () [username]
sudo (superuser do) : root .
su root /etc/sudoer .
sudo s : root
su sudo . su substitute user . username . username root .
(-) . su , , . , . . su username , user . , , home , logout .
sudo superuser do root root . sudo su root . sudo sudoer .
sudo s su su ? 6
. PC BIOS. , init . .
. PC , basic input/output system (BIOS). . RAM . 512 . 2 RAM RAM ( ) . 2 . 2 , . - (init) .
http://www.ibm.com/developerworks/kr/library/l-linuxboot/