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 AI检测代码解析 #!/bin/bash # List of values for item in apple banana che...
2、添加10个用户user1-user10,密码为8位随机字符 for user in user{1..10} ;do id $user &> /dev/null if [[ $? -ne 0 ]] ;then useradd $user #openssl rand -base64 6 ; uuidgen |cut -c8 pw=`openssl rand -base64 6` echo $pw|passwd --stdin $user &> /dev/null echo "user:...
# 自定义列表forloopin12345doecho"loop=$loop"doneexit0deyuy/bin/my_shell >>chmodu+x for1.shdeyuy/bin/my_shell >> ./for1.shloop=1loop=2loop=3loop=4loop=5还可以通过读取文件内容生成变量列表deyuy/bin/my_shell >>vim num.txt12345 6 7 8 #!/bin/bash # Program: # This program will...
Purpose 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 breakalways exits with an exit status...
In this final chapter on flow control, we will look at another of the shell’s looping constructs.The for loop differs from the while and until loops in that it providesa means of processing sequences during a loop. This turns out to be very useful when programming.Accordingly, the for ...
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 ...
学习shell脚本 2019-12-20 17:41 − 脚本执行方式: source:用这个命令执行shell脚本的时候,不会创建新的bash(子进程),可以直接在父进程中执行,所以shell里面的变量会被改变。 sh script和./script:会创建子进程,在子进程里执行完shell后,父进程里的变量不会改变。 ... PYozo_free 0 326 shell一文入门...
当变量值在列表里,for循环即执行一次所有命令,使用变量名获取列表中的当前取值。命令可为任何有效的shell命令和语句。in列表可以包含替换、字符串和文件名。 in列表是可选的,如果不用它,for循环使用命令行的位置参数。 例如,顺序输出当前列表中的数字:
via the command line. Converting this loop structure into a Bash script is also trivial. In this article, we show you some examples of how aforloop can make you look like a command line hero, and then we take some of those examples and put them inside a more structured Bash script. ...
ShellCheck can make suggestions for improving the robustness of a script:rm -rf "$STEAMROOT/"* # Catastrophic rm touch ./-l; ls * # Globs that could become options find . -exec sh -c 'a && b {}' \; # Find -exec shell injection printf "Hello $name" # Variables in printf ...