shell编程--for循环

Posted 2020-10-31

脚本

[[email protected] shell]# vim for1.sh

#!/bin/bash
for i in `seq 1 6`
do
      echo $i
done

执行结果

[[email protected] shell]# sh for1.sh
1
2
3
4
5
6

脚本

[[email protected] shell]# vim for2.sh

#!/bin/bash
sum=0
for i in `seq 1 6`
do
       echo "$sum + $i"
       sum=$[$sum+$i]
       echo $sum
done

执行结果

[[email protected] shell]# sh for2.sh
0 + 1
1
1 + 2
3
3 + 3
6
6 + 4
10
10 + 5
15
15 + 6
21

for循环是以空格或者回车来作为分割符来循环的

[[email protected] shell]# mkdir test
[[email protected] shell]# cd test
[[email protected] test]# touch 1 2
[[email protected] test]# touch 3\ 4.txt
[[email protected] test]# ls -l
总用量 0
-rw-r--r-- 1 root root 0 4月  20 08:13 1
-rw-r--r-- 1 root root 0 4月  20 08:13 2
-rw-r--r-- 1 root root 0 4月  20 08:13 3 4.txt
[[email protected] test]# for i in `ls ./ `; do echo $i ; done
1
2
3
4.txt