In this tutorial, we’ll take a look at using user input as awhileloop condition in the Linux shell. 2. UnderstandingwhileLoops Before we dive into using user input, let’s first discuss the concept and syntax of awhileloop: while [condition]; do # Code block done Let’s break down ...
The syntax of the while loop Multiple examples of the while loop So let's start with the first one. How to use the while loop in bash Like any other loop, while loop does have a condition statement and the condition is the crucial factor to iterate the loop. See, whenever you start ...
The while Loop SyntaxA while loop in bash consists of a conditional expression and a loop body which is surrounded by do and done. The loop body continues to be executed as long as the condition evaluates to true. The conditional expression in while loop can be surrounded by either a pair...
Shell while 循环while 循环用于不断执行一系列命令,也用于从输入文件中读取数据;命令通常为测试条件。其格式为:while command do Statement(s) to be executed if command is true done命令执行完毕,控制返回循环顶部,从头开始直至测试条件为假。以下是一个基本的 while 循环,测试条件是:如果 COUNTER 小于5,那么...
Let’s break downwhile loopsyntax. while loopshould start with a while keyword followed by a condition. Aconditionshould be enclosed within[ ]or[[ ]]. The condition should always return true for the loop to be executed. The actual block of code will be placed betweendoanddone. ...
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:...
Bash While Loop Another iteration statement offered by the shell programming language is the while statement. Syntax: while expression do commands done In the above while loop syntax: while, do, done are keywords Expression is any expression which returns a scalar value ...
The syntax is as follows. while [condition] do if [condition] then break fi Commands_to_Execute done For example, the below-given Bash script is printing numbers 1 to 5 to the standard output. Use thebreakstatement to exit the loop when the counter reaches 4. ...
bash shell if-statement while-loop m3u 我正在编写一个脚本来解析m3u文件。目标是检索变量标记和url。我用这个文件做了测试。 #!/bin/bash echo "name,tvg-id,tvg-name,tvg-country,group-title,languages,url" while IFS= read -r line; do tags_detect="$(echo "$line" | grep -Eo '^#EXTINF:')...
Awk While Loop Syntax: while(condition) actions while is a keyword. condition is conditional expression actions are body of the while loop which can have one or more statement. If actions has more than one statement, it has to be enclosed with in the curly braces. ...