Linux > BASH编程

BASH编程

bash脚本军规

脚本以shebang开头。例如：
```
#!/bin/bash
```

shebang下面紧跟一行注释，表示脚本的用途，例如：

# This script creates a backup of every MySQL database on the system.

下面紧跟全局变量声明，并赋值：
```
DEBUG=true 
HTML_DIR=/var/www 
```
函数应该注意使用局部变量，例如：
```
local GREETING="Hello!" 
```
所有函数声明放到上半部分，shell主体应该在函数的下面
脚本退出应该有明确的exit status, 例如:
```
exit 0 
```

模板如下：

#!/bin/bash 
# 
# <Replace with the description and/or purpose of this shell script.> 
 
GLOBAL_VAR1="one" 
GLOBAL_VAR2="two" 
 
function function_one() { 
  local LOCAL_VAR1="one" 
  # <Replace with function code.> 
} 
 
# Main body of the shell script starts here. 
# 
# <Replace with the main commands of your shell script.> 
 
# Exit with an explicit exit status. 
exit 0