有的变量还可以在子Shell进程中使用,这叫做环境变量(environment variable)。 有的变量只可可以在当前 Shell 进程中使用,这叫做全局变量(global variable); 有的变量只能在函数内部使用,这叫做局部变量(local variable); 1.1 Shell 局部变量 Shell 也支持自定义函数,但是 Shell 函数和 C++、Java、C# 等其他编程语言...
gvar="Global content changed"echo-e"Global variable value with in the function"echo $gvar}gvar="Global content"echo-e"Global variable value before calling function"echo $gvar echo-e"Local variable value before calling function"echo $lvar pprint echo-e"Global variable value after calling function"...
The examples below show how to define a function with the two shell grouping commands, parentheses () and braces {}. The last example shows how the global variable used in the function is unchanged after being executed in a subshell via the parentheses () command grouping notation. ...
$ cat test8 #!/bin/bash # using a global variable to pass a value function dbl { value=$[ $value * 2 ] } read -p "Enter a value: " value dbl echo "The new value is: $value" $ $ ./test8 Enter a value: 450 The new value is: 900 1. 2. 3. 4. 5. 6. 7. 8. 9....
have local variables with the same name in different functions. local func_result="Hello $1" # In Bash all variables by default are defined as global, # even if declared inside the function. global_result="some result" # Another, better option to return a value from a function ...
I am local_var defined in function func I am global_var difined in function func. Bash数组 Bash 只支持一维数组,用圆括号()来表示,数组元素之间用"空格"符号来分割(不同于C、C++、Java等语言中用逗号分割)。 数组的定义与初始化 初始化时不需要指定数组的大小。和其它大部分语言一样,bash数组元素的...
<functionname>(){ <commands>; } 2. The alternative way to write a bash function is using the reserved wordfunction: function<functionname> { <commands> } Or in one line: function<functionname> { <commands>; } Take note of the following behaviors and tips when using functions: ...
Bash functions, unlike functions in most programming languagesdo not allow you to return a value tothe caller. When a bash function endsits return value is its status: zero for success, non-zero for failure.To return values, you canset a global variable with the result, or use command sub...
函数内部,variable1=GLOBAL,variable2=LOCAL 函数外部,variable1=GLOBAL,variable2= ?问号也是一个变量,通过$?可以引用上一条命令的返回值,但是该值只能使用一次,使用完以后就会被目前命令的返回值所替换。 pi@raspberrypi:~ $false# false 命令返的回值恒为 1pi@raspberrypi:~ $echo$?1# 使用 echo 查看 1 ...
linux系统后门查杀常见检查目录和内容 .net 程序在访问提示无法执行程序 SQL Server 中“错误15023:当前数据库中已存在用户或角色” Linux下lsof命令详解 Discuz!新安装报错配置文件 "config_global.php" 未找到或者无法访问, 请确认您已经正确安装了程序 修改Apache配置文件 htaccess 文件实现自定义404页面 MySQL数据库...