Write a Bash script that declares two variables, "firstName" and "lastName", and assign them your first name and last name, respectively. Print a message greeting yourself using variable interpolation. Code: #!/bin/bash # Shebang line: Indicates the path to the shell interpreter (in this ...
#+ and simultaneously assigning it a value. echo "var2 declared as $var2" # Attempt to change readonly variable. echo echo "Change the var2's values to 13.37" var2=13.37 # Generates error message, and exit from script. echo "var2 is still $var2" # This line will not execute. ex...
-bash: sum: readonly variable <==老天爷～不能改这个变数了! declare 也是个很有用的功能～尤其是当我们需要使用到底下的数组功能时, 他也可以帮我们宣告数组的属性喔!不过,老话一句,数组也是在 shell script 比较常用的啦! 数组属性 array 说明 在bash 里头,数组的设定方式是: var[index]=content 范例:设...
# 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: \$@ $@" # ...
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...
编写shell script的良好习惯 1.文件头处记录 1.script的功能; 2.script的版本; 3.script的作者与联络方式; 4.script的历史记录; 5.script内较特殊的命令,最好使用“绝对路径”的方式来执行; 6.script执行时需要的环境变量预先生命与设置。 同时,根其他编码一样,添加适当的注释,整齐的缩进排版都是很重要的。
When creating scripts, we should take into account that every binary shell file starts with what is commonly known as "she-bang" (also known as sh-bang or hashbang). This is the beginning of the script title, and the first line of code indicates which shell you will use. When making ...
/bin/bash # declare STRING variable STRING="Hello World" #print variable on a screen echo $STRING Navigate to a directory where your hello_world.sh is located and make the file executable: $ chmod +x hello_world.sh Now you are ready to execute your first bash script:...
# 取消变量的值 unset my_variable 还可以使用环境变量为变量赋值。例如,可以使用$PATH环境变量: 代码语言:txt 复制 # 使用环境变量为变量赋值 current_path=$PATH echo "当前的PATH环境变量值为:$current_path" 参考链接: Bash变量赋值 相关搜索: linux bash 变量赋值 在bash中赋值位置变量 如何为bash中的布尔值...
declare -x name[=value] 查看所有环境变量:env, printenv, export 销毁环境变量: unset name bash脚本编程,其实就是文本文件,要运行脚本,其实就是运行一个bash进程,由bash进程解释并运行。 启动脚本: (1) # bash /PATH/TO/SCRIPT_FILE (2) 给bash脚本一个执行权限, 在命令行输入: ...