In a shell script, aforloop allows you to iterate over a set of values or a range of numbers. Here are a few examples of how to useforloops in different contexts: Example 1: Iterating Over a List of Values #!/bin/bash # List of values for item in apple banana cherry do echo "...
it will not use the positional parameter as shown below. It will not go inside the loop. i.e for loop will never get executed as shown in the example below.
commands: The commands can be any operating-system commands, a user program, a shell script, or a shell statement that returns (produces) a list. The value of the variable var is set to the first word in the list the first time through the loop. The second time through the loop, its...
Another example is, whilecreating AMI images using a packer, you will end up using a shell script for the AMI configuration. Also, I have had instances where I had to useshell scripts with configuration management tools,containers, etc. We will talk more about this in the following sections...
1. Static values for the list after “in” keyword In the following example, the list of values (Mon, Tue, Wed, Thu and Fri) are directly given after the keyword “in” in the bash for loop. $ cat for1.sh i=1 for day in Mon Tue Wed Thu Fri ...
<loop-body> done until (( <conditional-expression> )); do <loop-body> done Example #1: The semantic difference betweenwhileanduntilcan be illustrated with the following two shell scripts. They produce exactly the same result. i=0 while [ $i -lt 100 ]; do ...
The previous example has only one command between the braces, but you can add many commands, which will be processed for each loop. The indent of commands between the braces is by convention to make the script easier to review. The indent is not a technical requirement,...
Example 2: Loop through an Array #!/bin/bash fruits=("Apple" "Banana" "Orange" "Grapes") for ((i = 0; i < ${#fruits[@]}; i++)); do echo "Fruit $((i+1)): ${fruits[i]}" done In the above code: fruits=(“Apple” “Banana” “Orange” “Grapes”) creates an array ...
shell脚本forloops&whileloops题解 一、for loops for 变量名 in 列表;do 循环体 done 执行机制: 依次将列表中的元素赋值给“变量名”; 每次赋值后即执行一次循环体; 直 到列表中的元素耗尽,循环结束 列表生成方式: (1) 直接给出列表 (2) 整数列表:...
(转) 一个从fedora7中拷贝过来的bash脚本,居然不能在ubuntu下面执行,提示错误 Bad for loop variable G了一把,在TW同胞那里找到了答案～原来是bash和dash的问题 解决方法: 使用 sudo dpkg-reconfigure dash 选择NO。。 世界又清静了~(经典!) 感谢link:http://hi.baidu.com/yk103/blog/item/1e9831fa3fc23d...