bash 中的字符串比较不起作用
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String comparison in bash is not working
提问by Reuben
Hi I'm new to bash scripting. Just wrote this simple program but it is throwing error.
嗨，我是 bash 脚本的新手。刚刚写了这个简单的程序，但它抛出了错误。
#!/bin/bash
os=`uname -o`
echo $os
if ["$os"=="GNU/Linux"] ; then
echo "Linux"
else
echo "Windows"
fi
Using == or -eq for both cases I'm getting the following error and it is printing the else condn.
在这两种情况下都使用 == 或 -eq 时，我收到以下错误，并且正在打印 else condn。
./ostype.sh: line 3: [GNU/Linux==GNU/Linux]: No such file or directory
./ostype.sh: 第 3 行: [GNU/Linux==GNU/Linux]: 没有那个文件或目录
Windows
视窗
Bash version : GNU bash, version 3.2.48(1)-release (x86_64-suse-linux-gnu)
Bash 版本：GNU bash，版本 3.2.48(1)-release (x86_64-suse-linux-gnu)
回答by yiding
try
尝试
if [ "$os" = "GNU/Linux" ]
note the spaces, and the single =.
注意空格和单个=.
[is actually a program, and the rest are arguments!
[实际上是一个程序，其余的都是参数！
回答by Shawn Chin
Use =for string comparison. See: http://tldp.org/LDP/abs/html/comparison-ops.html
使用=的字符串比较。请参阅：http: //tldp.org/LDP/abs/html/comparison-ops.html
Also, there should be a space around the square brackets and the comparison operator, i.e.
此外，方括号和比较运算符周围应该有一个空格，即
if [ "$os" = "GNU/Linux" ]; then
^ ^ ^ ^ ^
| | | | |
\-\-----\-\-----------\-- (need spaces here)
