Bash超级会 - 5.LOOP 每种编程语言都有 loop 操作,在 bash script 中,有两种 loop 。 while 没数的时候就用While吧,没数但必须说一个条件。 #!/bin/bash i=0 while [ $i -le 4 ] do echo Number: $i ((i++)) done for 数数或者数list。 #!/bin/bash i=2 for (( counter=1; counter<...
你也可以从0开始,跳过最后一个,在循环外处理(上面的镜像),但是跳过最后一个通常比较脏,而且可能是不可能的(要跳过最后一个,你必须知道它是最后一个,但第一个总是可以立即跳过)。例如,如果您正在从流中读取元素,您无法提前知道哪一个是最后一个,而这种形式是唯一的选择! 另一种方式: # test a loop counterN...
for((i=0;i<=1000;i++));doecho"Counter:$i"done 循环将迭代1001次,并产生以下输出: Counter:0Counter:1Counter:2... Counter:998Counter:999Counter:1000 break和continue声明 break和continue语句可用于控制for循环的执行。 break声明 break语句终止当前循环,并将程序控制权传递给终止语句之后的语句。它通常用...
After each iteration of the loop, expr3 is evaluated. This is usually used to increment a loop counter. The following 12 examples shows how to bash for loops in different ways. 1. Static values for the list after “in” keyword In the following example, the list of values (Mon, Tue, ...
Condition- Condition should be true for the loop to be executed else the loop will not run. Counter- This will increment the variable value. Each parameter should be separated by asemicolon(;) and should be enclosed indouble bracketsas shown below. ...
BASH if/while/until loop #1/bin/bashif[ $# -eq1];thencounter="1"counter1="1"echo"for loop:"foriin$(seq1$1);doecho$idoneforiin$(seq1320);doecho"welcome $i times"donefor((i=1;i<3;i++));doecho$idoneecho"while loop"while[ $counter -le $1];doecho$counter...
After each iteration of the loop, expr3 is evaluated. This is usually used to increment a loop counter. The following 12 examples shows how to bash for loops in different ways. 1. Static values for the list after “in” keyword
Bash example for the += and -= counter operators in a while loop: #!/bin/bash num=0 while(($num<6)) do echo "num:" $num ((num+=1)) done Script output: foc@fedora:/tmp$ ./counter.sh num: 0 num: 1 num: 2 num: 3 num: 4 num: 5 You can also write let num+=1 ins...
printf “The counter is now %d/n” “$COUNTER” done exit 0 当循环开始时,执行双括号中的第一个表达式,每次循环开始执行第三个表达式,并检查第二个表达式,当第二个表达式返回 false ,循环结束。 $ bash forloop.sh The counter is now 1 The counter is now 2 ...
Write a Bash script that utilizes a while loop to count down from 10 to 1 and then prints "Bash Script!". Code: #!/bin/bash# Initializing the counterctr=10# Using a while loop to count down from 10 to 1while[$ctr-gt0]doecho$ctr((ctr--))done# Printing "Bash Script!" after th...