Bash 脚本 - 文件目录不存在
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Bash script - File directory does not exist
提问by imprudent student
I'm creating a very simple bash script that will check to see if the directory exists, and if it doesn't, create one.
我正在创建一个非常简单的 bash 脚本，它将检查目录是否存在，如果不存在，则创建一个。
However, no matter what directory I put in it doesn't find it!
但是，无论我放在哪个目录中都找不到它！
Please tell me what I'm doing wrong.
请告诉我我做错了什么。
Here is my script.
这是我的脚本。
#!/bin/bash
="/media/student/System"
if [ ! -d ]
then
mkdir
fi
Here is the command line error:
这是命令行错误：
./test1.sh: line 2: =/media/student/System: No such file or directory
回答by yunzen
Try this
尝试这个
#!/bin/bash
directory="/media/student/System"
if [ ! -d "${directory}" ]
then
mkdir "${directory}"
fi
or even shorter with the parentargument of mkdir (manpage of mkdir)
甚至更短parent的 mkdir 参数（ mkdir 的联机帮助页）
#!/bin/bash
directory="/media/student/System"
mkdir -p "${directory}"
回答by 0.sh
In bash you are not allow to start a variable with a number or a symbol except for an underscore _. In your code you used $1, what you did there was trying to assign "/media/student/System"to $1, i think maybe you misunderstood how arguments in bash work. I think this is what you want
在 bash 中，您不允许以数字或符号开头，但下划线除外_。在您使用的代码中$1，您所做的尝试分配"/media/student/System"给$1，我想您可能误解了 bash 中的参数是如何工作的。我想这就是你想要的
#!/bin/bash
directory="" # you have to quote to avoid white space splitting
if [[ ! -d "${directory}" ]];then
mkdir "$directory"
fi
run the script like this
像这样运行脚本
$ chmod +x create_dir.sh
$ ./create_dir.sh "/media/student/System"
What the piece of code does is to check if the "/media/student/System" is a directory, if it is not a directory it creates the directory
这段代码的作用是检查“/media/student/System”是否是目录，如果不是目录，则创建目录
