ls file directory

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ls file directory

ls l file directory permission

ls a file directory ls la file directory permission

man ls ls

cd root directory root

cd Desktop directory Desktop

pwd

less /etc/passwd passwd 1 spacebar

cp tim test tim test

rm testvi testvi

tail /etc/passwd passwd 10

mv tim test2 tim test2

cat /etc/passwd passwd

grep root /etc/passwd root passwd

vi 025-9 vi

vi I enter , spacebar

esc x , DD ,zz Shift + : q! vi , w

/boot file upgrade kernel /var file data service log service / logrotate log /var/log logrotate log 90 /usr file /usr/bin, /usr/sbin Source Kernel /usr/share/doc

/tmp file application /tmp /etc