大数据第二次作业
---恢复内容开始---
(1)cd /usr/local
(2)cd ../
(3)cd
(4)ls -al /usr
(5)
cd /tmp
mkdir a
ls
(6)mkdir -p a1/a2/a3/a4
(7)rmdir a
(8)
rmdir -p a1/a2/a3/a4
ls
(9)cp .bashrc /usr/bashrc1
(10)
mkdir /tmp/test
cp -r /tmp/test /usr
(11)mv /usr/bashrc1 /usr/test
(12)mv /usr/test /usr/test2
(13)rm /usr/test2/bashrc1
(14)rm -r /usr/test2
(15)cat .bashrc
(16)tac .bashrc
(17)more .bashrc
(18)head -n 20 .bashrc
(19)head -n -50 .bashrc
(20)tail -n 20 .bashrc
(21)tail -n +50 .bashrc
(22)
touch /tmp/hello
ls -l /tmp/hello
(23)touch --date="5 days ago" /tmp/hello
(24)
chown root /tmp/hello
ls -l /tmp/hello
(25)find .bashrc -type f
(26)
cd /
tar -czvf test.tar.gz test
(27)
tar -xzvf test.tar.gz -C /tmp
(28)
grep examples ~/.bashrc
(29)export JAVA_HOME=/usr/bin/lib/java
(30)echo $JAVA_HOME