until语句 :提供循环执行,它与while循环相反, until循环将反复执行直到条件为真就结束循环,而while循环条件为假就结束循环。

使用格式:

until [ 测试条件 ]

do

语句 #可以是多条语句

done

例1:

#!/bin/sh
var=10
until [ $var -gt 1 ]
do
echo $var
var=$(($var - 1))
done
exit 0

 

例2:

 

#!/bin/bash

#filename:hk

echo "This example is for testuntil....do "

echo "If you input [exit] then quitthe system "

echo -n "please input:"

read EXIT

until [ $EXIT = "exit" ]

do

read EXIT

done

echo "OK!"

 

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