好程序员云计算教程分享 Shell 编程之 for 循环结构
No.1 for循环结构
for
i
in
{取值范围}
do
循环体
done
求取1-100数字的和、找出1-100中能被2整除的数字、找出1-100中的素数、找出1-100种能被3整除的数字
#!/usr/bin/env bash
#
# Author: bavdu
# Email: bavduer@163.com
# Github: https://github.com/bavdu
# Date: 2019/**/**
sum
=
0
for
i
in
{1..100}
do
let
total
=
$sum
+
$i
#或者写成let total=i++
done
printf
"
$total
\n"
测试生产环境中的主机存活性
#!/usr/bin/env bash
#
# Author: bavdu
# Email: bavduer@163.com
# Github: https://github.com/bavdu
# Date: 2019/**/**
>ip_alive.txt
>ip_down.txt
export
segment
=
"192.168.161"
for
i
in
{2..254}
do
{
ping
-c1
$segment
.
$i
&>/dev/null
if
[
$?
-eq
0
];then
printf
"alive:
$segment
.
$i
\n"
>>ip_alive.txt
else
printf
"down:
$segment
.
$i
\n"
>>ip_down.txt
fi
}&
done
wait
printf
"
$(date +%Y-%m-%d_%k:%M:%S)
-exec filename:
$0
\n"
来自 “ ITPUB博客 ” ，链接：https://blog.itpub.net/69913892/viewspace-2665218/ ，如需转载，请注明出处，否则将追究法律责任。
