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