bash - 如何在shell脚本中执行逻辑OR操作(How to do a logical OR operation in shell scripting)

Question

I am trying to do a simple condition check, but it doesn't seem to work.

(我正在尝试进行简单的条件检查，但它似乎不起作用。)

If $# is equal to 0 or is greater than 1 then say hello.

(如果$#等于0或大于1则说出你好。)

I have tried the following syntax with no success:

(我尝试了以下语法但没有成功：)

if [ "$#" == 0 -o "$#" > 1 ] ; then
 echo "hello"
fi

if [ "$#" == 0 ] || [ "$#" > 1 ] ; then
 echo "hello"
fi

  ask by Strawberry translate from so

Answer 1

This should work:

(这应该工作：)

#!/bin/bash

if [ "$#" -eq 0 ] || [ "$#" -gt 1 ] ; then
    echo "hello"
fi

I'm not sure if this is different in other shells but if you wish to use <, >, you need to put them inside double parenthesis like so:

(我不确定这在其他shell中是否有所不同，但是如果你想使用<，>，你需要将它们放在双括号内，如下所示：)

if (("$#" > 1))
 ...