shell中所有循环语法（shell怎么写循环）

for i in $(ls)
do 
	echo $i 
done

while循环

#!/bin/bash 
counter=0
while [$counter -lt 10]
do
	echo $counter
	let counter=counter+1
done

until循环

#!/bin/bash 
counter=20
until [$counter -lt 10]
do 
	echo $counter
	let counter -=1
done