引用名称包含点的 bash 变量
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Reference to a bash variable whose name contains dot
提问by Taher Khorshidi
I have a bash variable: agent1.ipwith 192.168.100.137as its value. When I refer to it in echolike this:
我有一个 bash 变量：agent1.ipwith192.168.100.137作为它的值。当我echo像这样提到它时：
echo $agent1.ip
the result is:
结果是：
.ip
How can I access the value?
如何访问该值？
UPDATE:my variables are:
更新：我的变量是：
回答by John Zwinck
Bash itself doesn't understand variable names with dots in them, but that doesn't mean you can't have such a variable in your environment. Here's an example of how to set it and get it all in one:
Bash 本身不理解带有点的变量名，但这并不意味着您的环境中不能有这样的变量。这是一个如何设置并将其全部整合的示例：
env 'agent1.ip=192.168.100.137' bash -c 'env | grep ^agent1\.ip= | cut -d= -f2-'
回答by chepner
Since bash.ipis not a valid identifier in bash, the environment string bash.ip=192.168.100.37is not used to create a shell variable on shell startup.
由于bash.ip不是 中的有效标识符bash，环境字符串bash.ip=192.168.100.37不用于在 shell 启动时创建 shell 变量。
I would use awk, a standard tool, to extract the value from the environment.
我会使用awk标准工具 来从环境中提取价值。
bash_ip=$(awk 'BEGIN {print ENVIRON["bash.ip"]}')
回答by nikolay
The cleanest solution is:
最干净的解决方案是：
echo path.data | awk '{print ENVIRON[]}'
回答by SMA
Try this:
尝试这个：
export myval=`env | grep agent1.port | awk -F'=' '{print }'`;echo $myval
回答by shellter
Is your code nested, and using functions or scripts that use ksh?
您的代码是否嵌套并使用了使用 ksh 的函数或脚本？
Dotted variable names are an advanced feature in ksh93. A simple case is
带点的变量名是 ksh93 中的一项高级功能。一个简单的案例是
$ a=1
$ a.b=123
$ echo ${a.b}
123
$ echo $a
1
If you first attempt to assign to a.b, you'll get
如果您第一次尝试分配给a.b，您将获得
-ksh: a.b=123: no parent
IHTH
IHTH
