如何从Bash中的返回码号中提取位

Question

我正在使用pylint实用程序，它返回以下错误代码：

Pylint should leave with following status code:

* 0 if everything went fine
* 1 if a fatal message was issued
* 2 if an error message was issued
* 4 if a warning message was issued
* 8 if a refactor message was issued
* 16 if a convention message was issued
* 32 on usage error

status 1 to 16 will be bit-ORed so you can know which different
categories has been issued by analysing pylint output status code

现在，我需要确定Bash中是否发生了致命或错误消息。怎么做？我想我需要这样做;-)

编辑：我知道我需要按位执行并与数字三（3）并针对null进行测试，以查看是否发出了致命消息或错误消息。我的问题很简单：使用bash语法即可。输入是$ ?，输出又是$？（例如，使用测试程序）。谢谢！

Answer 1

在 Bash 中你可以使用双括号：

#fatal error
errorcode=7
(( res = errorcode & 3 ))
[[ $res != 0 ]] && echo "Fatal Error"