#!/bin/bash
sum=0
for i in `seq 1 100`
#seq 1到100个数字
do
sum=$[$sum+$i]
echo $i
done
echo $sum
#!/bin/bash
cd /etc/
for a in `ls /etc/`
do
if [ -d $a ]
then
ls -d $a
fi
done
[root@hf-01 shell]# for a in `seq 1 3`; do echo $a; done
1
2
3
[root@hf-01 shell]# for a in 1 2 3; do echo $a; done
1
2
3
[root@hf-01 shell]#