fruit=orange; and on the third and final iteration,fruit=pear. Once it has completed the loop, the script continues normal execution with the next command after thedonestatement. In this case, it ends by saying
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. ...
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 "...
[root@www shell-script]# cat c_for02.sh#!/bin/bashfor((i=1,j=100;i<=10;i++,j--))doecho"i=$ij=$j"done 1. 2. 3. 4. 5. 6. for的无限循环 #!/bin/bashfor((i=0;i<1;i+=0))doecho"infinite loop"done 1. 2. 3. 4. 5. while循环 和for循环一样,while循环也是一种运...
for (( i=1; i<=100; i++ )) do s=$(( $s + $i )) done echo $s sh add.sh 报错: add.sh: 4: Syntax error: Bad for loop variable 代码没有错误,Ubuntu为了加快开机速度,用dash取代bash。 解决的方法:取消dash,使用bash: sudo dpkg-reconfigure dash ...
shell 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 惨绿少年 2017/12/27 3.4K0 基于网传的shell脚本,进行简单优化 bashbash 指令unixphplinux [root@localhost ~]# sed 'N;s/\n/:...
For example, you can add the nested loop example to a Bash script to improve its readability, like this: $vimcopy_web_files.sh# !/bin/bashforiinfile{1..3};doforxinweb{0..3};doecho"Copying$ito server$x"scp$i$xdonedone When you save and execute this script, the result is the ...
在linux下写了一个简单的shell,循环10次. test.sh #!/bin/bash ## ##循环10次 ##for((i=0; i<10; i++));doecho Good Morning ,thisis$i shell program. done 执行:sh test.sh 报下面的错误. Syntax error: Bad for loop variable
This is a very useful way to filter the results, which would be cumbersome and time-consuming in a for or while loop in a shell script. The uniq command is also rather unique in that if passed a second filename on the command line, it will write the output to that file instead of ...
bash -c ‘COMMAND’runsCOMMANDas a Bash shell script (we can also use the regularsh) > output.logsaves the command output to a log file &puts everything in the background Let’s runnohup, using ourforloop in the place ofCOMMAND: ...