登录后复制# The script is:str="str len"echo"Method1:"${#str}length=`expr length"$str"`echo"Method2:"$lengthlength=`expr"$str":'.*'`echo"Method3:"$lengthlength=`echo-n$str| wc -c`echo"Method4:"$lengthlength=`echo-n$str| awk'{print length}'`echo"Method5:"$length# The resul...
用户可以用 Shell 命令写出各种小程序,又称为脚本(script) • Bourne Again shell(bash) ~= • Bourne Shell(sh) # bash --version • Z Shell(zsh) Bash 使用空格(或 Tab 键)区分不同的参数。 分号(;)是命令的结束符 Bash 还提供两个命令组合符&&和|| echo输出的文本末尾会有一个回车符。-n参...
# 位置参数调用, 假设在终端输入 bash bash_tutorial.sh 1 2 3 echo "current script name: \$0 $0" # 当前脚本名称 echo "incoming parameters: \$1 $1 \$2 $2 \$3 $3" # 访问传入的参数 echo "the number of parameters: \$# $#" # 传入的参数数量 echo "all parameters: \$@ $@" # ...
resource "null_resource" "example" { provisioner "local-exec" { command = "bash script.sh" } } 在上述示例中,script.sh是一个bash脚本文件,它将在Terraform部署完成后执行。 需要注意的是,为了确保安全性和可维护性,建议将bash脚本的输入参数化,并通过Terraform的来传递。这样可以使脚本更加灵活和可配置。
bash 里面引用一个变量的过程称为 Variable Substitution,字面意思即为变量替换。和大多数的语言叫法不同,但实际用起来没啥区别。 其实上面的赋值就有不少替换了,这里我们更进一步。 代码语言:javascript 代码运行次数:0 运行 AI代码解释 # 替换,必须有美元符号 ...
1. Identify String Length inside Bash Shell Script ${#string} The above format is used to get the length of the given bash variable. $catlen.sh#! /bin/bash var="Welcome to the geekstuff"echo${#var} $ ./len.sh24 To understand more about bash variables, read6 Practical Bash Global ...
case$BASE_VERSIONin[12].*)echo"You need at least bash3.0 to run this script">&2; exit2;;esac 提示符PS1,PS2用于命令行中的shell交互时,PS3在使用内置命令select时使用,PS4用于在执行跟踪模式下,每行之前的打印。 Shell变量包含: BASH BASHOPTS BASHPID BASH_ALIASES ...
bash: unset: place:无法重置:只读的 variable 从标准输入设备读入 read [options][variable-list] 用于从标准输入设备读入一行,把读入的词赋给在variable-list中的变量 yaoyuan@yaoyuan-desktop:~/ScriptFile$ cat read_demo #! /bin/bash echo -n "Enter input: " ...
This bash script uses the "uptime" and "date" commands to get information about the system uptime and current date. The script starts by creating a string variable named "today" and assigning the result of the "date" command to it. The script then outputs a message which includes the stri...
In this code block, we first assign the value of$RANDOMto the variablerandom_number. Then, we print the value ofrandom_numberusing theechocommand. Each time you run this script, a new random number between 0 and 32767 will be printed. ...