Linux Advanced Bash Programming (Process Control-while,break,continue)

In bash programming, it often involves using while statements to deal with the number of unknown loops at times.

1. While syntax

While [Express]do#commanddone

2. Practical Practice

• Prompt to enter an integer greater than 10 less than 20;

While1.sh:#!/bin/bashecho-n "Please input a digit between:" Read Nwhile [$n-lt 10]| | [$n-gt]doecho-n "Please input a digit between and:" Read Ndoneecho "Your digit is $n, thank you!"

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• Guess the number, guessed the end;

While2.sh:#!/bin/bashecho-n "Please guess a number between 0 and ten:" Read Nwhile [$n-ne 8]doecho-n "Please guess Agai N (0-10): "Read Ndoneecho" Congratulation,you guessed! The lucky number is 8! "

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• control while using parameters that are brought in when the script is executed
  

While3.sh:#!/bin/bashn=$1while [-N "$n"] ["$n"-GT 0]doecho-n "*" Let N--done-------------------------$bash while3. SH 5$*****

• About the use of break and continue. The keyword "break" is used to jump out of the loop, and the keyword "continue" is used to skip to the next loop without executing the rest of the section.

While4.sh:#!/bin/bashn=$1while [-N $n]do if [$n-eq 0]then echo-e "" Breakelse echo-n "*" Let n--continue Fidone execution: $bash while4.sh 5*****

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Linux Advanced Bash Programming (Process Control-while,break,continue)