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This article introduces the relevant knowledge of "what is the difference between single quotation marks (') and double quotation marks (") in Shell scripts? in the operation of actual cases, many people will encounter such a dilemma. Then let the editor lead you to learn how to deal with these situations! I hope you can read it carefully and be able to achieve something!

When writing a Shell script on the Linux operating system, we use the $symbol in front of the variable to get the value of the variable. We usually use the "$param" format with double quotes in the script, but there are also scenarios where'$param' is used in quotation marks. First, let's take a look at an example:

The code is as follows:

[root@linux ~] # name=TekTea

[root@linux ~] # echo $name

TekTea

[root@linux ~] # sayhello= "Hello $name"

[root@linux ~] # echo $sayhello

Hello TekTea

[root@linux ~] # sayhello='Hello $name'

[root@linux ~] # echo $sayhello

Hello $name

Did you find out? That's right! When single quotation marks are used, the $name will lose its original variable content, just the display type of a normal character! You have to be very careful here!

Therefore, the biggest difference between single quotation marks and double quotation marks is that double quotation marks can still hold the contents of variables, but there can only be general characters inside single quotation marks, but there will be no special symbols. We can also understand here that'$sayhello''is the same as "\ $sayhello".

During the development of Shell scripts, both single quotation marks (') and double quotation marks (") for variables have application scenarios, which can be summed up in my experience:

1. Double quotation marks (") are used when getting the value of a variable, which is the basic usage.

two。 If you are writing a new script in a script and you need to include variables in the new script, you can choose to use single quotes ('), especially when generating a temporary expect script.

This is the content of "what is the difference between single quotation marks (') and double quotation marks (") in the Shell script? thank you for your reading. if you want to know more about the industry, you can follow the website, the editor will output more high-quality practical articles!

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