Reading a file into a variable in Bash
Sometimes when dealing with files, we may need to place the text file in a variable in order to perform some necessary operations on the file. In Bash Script, this is a very easy task that does not require more than two lines of code.
This article will show how we can get a file in a variable. Also, we will see necessary examples and proper explanations to make the topic easier to understand.
The text file to save into a variable
Before we begin, assume we have a text file with the following content:
This is the first line.
This is the second line.
This is the third line.
This is the fourth line.
Now, we will use the following three methods one by one to get the file into a variable,
Reading a file into a variable using cat keyword in Bash
In our following method example, we will use the Bash's built-in keyword "cat." This keyword is mainly used to read any file.
The code for our example is as follows:
FileText= cat 1_Test.txt
echo "$FileText"
In the above example, we are simply reading a text file using cat 1_Test.txt and assigning the data to a variable called FileText and then printing the data stored in the variable.
After executing the above Bash script, you will get the output as follows:
This is the first line.
This is the second line.
This is the third line.
This is the fourth line.
Reading a file into a variable in Bash without using the cat keyword
This method will perform the same task but will not use the keyword cat. You can put a text file into a variable as shown in the following example.
FileText=$(<1_Test.txt)
echo "$FileText"
In the above example, we are simply $(<1_Test.txt)reading a text file using and assigning the data to a variable called FileText. After that, we print the data stored in the variable.
After executing the above Bash script, you will get the output as follows:
This is the first line.
This is the second line.
This is the third line.
This is the fourth line.
You can choose any of the above methods according to your preference.
请注意, all the codes used in this article are written in Bash. It will only work in Linux Shell environment.
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