Example 1: Infinite While loop in a shell script An infinite While loop means your script will run the loop commands non-stop. Infinite While loops never stop running and this occurs when the condition always turns out to be “True.” You can create an infinite While loop with the followin...
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. #!/bin/bash i=0 while [ $i -lt 5 ] do i=$(( $i+1 )) if [ $i -eq 4 ] then break fi echo $i done Bash while...
WHILE loop - read line of a file one by one, I'm using a "while" loop within a shell script (BASH) to read line of a file (one by one) -- "Fortunately", its not working the No. of times the file has lines in it. Here's the summary: $ cat inputfile.txt Utilizing For L...
Shell scripting, specifically Bash scripting, is a great way to automate repetitive or tedious tasks on your systems. Why type when you can schedule and run scripts in a hands-free manner? One of the many scripting constructs is the loop. A loop is a section of code that picks up data ...
In shell scripting, using user input as a condition for awhileloop adds dynamic executionas it enables us to control the flow of the script based on their input. 3.1. Prompting for User Input To demonstrate, let’s utilize thereadcommand to prompt the user: ...
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:...
Not all shells support C-styleforloops, so using multiple variables in such loops may not be universally applicable across different shell environments. First, let’s consider a simple shellforloop: $ cat simple_for.sh #!/bin/bash echo "Simple for loop example:" ...
breakexits from afor,select,while, oruntilloop in a shell script. Ifnumberis given,breakexits from the given number of enclosing loops. The default value ofnumberis1. Usage Notes This is a special built-in command of the shell. Exit Values ...
Here is a sample shell code to calculate factorial using while loop: #!/bin/bashcounter=$1factorial=1while[$counter-gt0]dofactorial=$(($factorial*$counter))counter=$(($counter-1))doneecho$factorial To run just type: $ chmod +x script.sh ...
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:')...