Cloud Computing Learning Route course Code Notes: Shell programming

This article is the content of the cloud computing learning route tutorial code notes about the for loop structure of Shell programming.

For i in {value range}

Do

Cyclic body

Done

Find the sum of the numbers from 1 to 100, the numbers divisible by 2 from 1 to 100, the primes from 1 to 100, and the numbers divisible by 3 from 1 to 100.

#! / usr/bin/env bash

#

Author: bavduEmail: bavduer@163.comGithub: https://github.com/bavduDate: 2019//

Sum=0

For i in {1..100}

Do

Let total=$sum+$i # or write as let total=i++

Done

Printf "$total\ n"

Test host viability in production environment

#! / usr/bin/env bash

#

Author: bavduEmail: bavduer@163.comGithub: https://github.com/bavduDate: 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"