在linux下一般用while read line与for循环按行读取文件。现有如下test.txt文件: 1. while read line whileread line;doecho $line done< test.txt 输出结果与上图一致。 这里也可以写为: cat test.txt |whileread line;doecho $line done 输出结果一致,但是需要注意一点,就是在如下情况下结果是不同的: # ...
One of the many scripting constructs is the loop. A loop is a section of code that picks up data or generates data and then performs some operation on the data and then begins the process over again until some condition is met, the script is disrupted, or when input data is exhausted. ...
1、判断/var/目录下所有文件的类型 for files in /var/* ;do if [[ -f $files ]];then echo "$files exists and is a regular file." elif [[ -h $files ]] ;then echo "$files is a symbolic link." elif [[ -d $files ]] ;then echo "$files is a directory." else echo "$files ...
在linux下一般用while read line与for循环按行读取文件。现有如下test.txt文件: 1. while read line whileread line;doecho $line done<test.txt 1. 2. 3. 复制 输出结果与上图一致。 这里也可以写为: cat test.txt|whileread line;doecho $line done 1. 2. 3. 复制 输出结果一致,但是需要注意一点,...
The range is specified by a beginning (#1) and ending number (#5). The for loop executes a sequence of commands for each member in a list of items. A representative example in BASH is as follows to display welcome message 5 times with for loop: 代码语言:txt 复制 #!/bin/bash for i...
在linux下一般用while read line与for循环按行读取文件。现有如下test.txt文件: 1. while read line 代码语言:javascript 复制 while read line; do echo $line done < test.txt 输出结果与上图一致。 这里也可以写为: 代码语言:javascript 复制 cat test.txt | while read line; do echo $line done 输出...
2. While循环 while循环会在给定的条件为真时不断执行一系列命令。whileconditiondocommandsdone 示例：打...
导读:在 Bash 基础知识系列的倒数第二章节,学习 for、while 和 until 循环。 本文字数:3087,阅读时长大约: 4分钟 https://linux.cn/article-16114-1.html 作者:Abhishek Prakash 译者:ChatGPT 在Bash 基础知识系列的倒数第二章节,学习 for、while 和 until 循环。
1.1 for循环语句在计算机科学中,for循环(英语:for loop)是一种编程语言的迭代陈述,能够让程式码反复的执行。 它跟其他的循环,如while循环,最大的不同,是它拥有一个循环计数器,或是循环变数。这使得f…
Method 2: Bash For Loop using C like syntax The second form of the for loop is similar to the for loop in “C” programming language, which has three expressions (initialization, condition and updation). for (( expr1; expr2; expr3 )) ...