Export Command in Linux

In this guide, we will look at the export command in Linux. Export is a built-in command of the Bash shell. It is used to mark variables and functions to be passed to child processes. Basically, a variable will be included in child process environments without affecting other environments. To get a clearer picture of what we are talking about, let’s dive in and have a look at the export command examples.

Export command in Linux without any arguments

Without any arguments, the command will generate or display all exported variables. Below is an example of the expected output.

Copy
$ export

Sample output

Viewing all exported variables on current shell

If you wish to view all exported variables on the current shell, use the -p flag as shown in the example

Copy
$ export -p 

Sample output

Using export with functions

Suppose you have a function and you wish to export it, how do you go about it? In this case , the -f flag is used. In this example, we are exporting the function name ().

First, call the function

Copy
$ name () { echo "Hello world"; }

Then export it using the -f flag

Copy
$ export -f name

Next, invoke bash shell

Copy
$ bash

Finally, call the function

Copy
$ name

Output

Copy
Hello World

You can also assign a value before exporting a function as shown

Copy
$ export name[=value]

For example, you can define a variable before exporting it as shown

Copy
$ student=Divya

In the above example, the variable ‘student’ has been assigned the value ‘Divya’

To export the variable run

Copy
$ export students

You can use the printenv command to verify the contents of the variable as shown

Copy
$ printenv students

Check the output below of the commands we have just executed

Output

The above can be achieved in 2 simple steps by declaring and exporting the variable in one line as shown

Copy
$ export student=Divya

To display the variable run

Copy
$ printenv student

Output

This concludes our tutorial about export command. Go ahead and give it a try and see the magic! Your feedback is most welcome.

About Pankaj

I love Open Source technologies and writing about my experience about them is my passion. You can connect with me directly on Facebook, Twitter, and YouTube.