linux shell 部分语法及练习

#! /bin/bash
# ********** homework_0 *********
homework 1 create 0
dir0=/home/acs/homework/lesson_1/homework_0
for i in a b c
do

    mkdir ${dir0}/dir_${i}

done

#*********** homework_1 ******
homework 1 create 1
dir1=/home/acs/homework/lesson_1/homework_1
for i in a.txt b.txt c.txt
do
    cp ${dir1}/${i} ${dir1}/${i}.bak
done

#**********homework_2********
dir2=/home/acs/homework/lesson_1/homework_2
for i in a b c
do
    mv ${dir2}/${ii}.txt ${dir2}/${i}_new.txt
done

#**********homework_3*********
dir3=/home/acs/homework/lesson_1/homework_3
for i in a.txt b.txt c.txt
do
    mv ${dir3}/dir_a/${i} ${dir3}/dir_b
done


#************homework4*********
homework 1 create 4
dir4=/home/acs/homework/lesson_1/homework_4
for i in a.txt b.txt c.txt
do
    rm ${dir4}/${i}
done

#*************homework5*****
homework 1 create 5
dir5=/home/acs/homework/lesson_1/homework_5
for i in dir_a dir_b dir_c
do
    rm ${dir5}/${i} -r
done

#******homework6*****
dir6=/home/acs/homework/lesson_1/homework_6
mkdir ${dir6}/dir_a
mv ${dir6}/task.txt ${dir6}/dir_a/"done.txt"

#*******homework7******
dir7=/home/acs/homework/lesson_1/homework_7
for i in 0 1 2
do
    mkdir ${dir7}/dir_${i}
    for j in a b c

    do


        cp ${dir7}/${j}.txt ${dir7}/dir_${i}/${j}${i}.txt
    done
done

#****homework8*******
dir8=/home/acs/homework/lesson_1/homework_8
rm ${dir8}/dir_a/a.txt
mv ${dir8}/dir_b/b.txt ${dir8}/dir_b/b_new.txt
cp ${dir8}/dir_c/c.txt ${dir8}/dir_c/c.txt.bak

#******homework9******
dir9=/home/acs/homework/lesson_1/homework_9
for i in 23 27 11 15 19 3 7
do
    rm ${dir9}/file_${i}.txt
done