export command in Linux CLI - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does the export command do in Linux?

The export command sets environment variables so that they are available to child processes started from the current shell.

beginner

How do you make a variable named MY_VAR available to other programs using export?

You write: export MY_VAR=value. This sets MY_VAR and exports it to child processes.

beginner

What happens if you set a variable without export?

The variable exists only in the current shell and is not passed to child processes or other programs.

beginner

How can you see all exported environment variables in your current shell?

Use the command export -p or printenv to list all exported environment variables.

intermediate

Can you export a variable that was already set without reassigning it?

Yes, just run export VARIABLE_NAME to export an existing variable without changing its value.

What does the export command do?

A Deletes a variable

B Lists all files in a directory

C Changes the shell prompt

D Makes a variable available to child processes

The export command marks variables to be passed to child processes.

Which command exports a variable named PATH with a new value?

A env PATH=/usr/bin

B export PATH=/usr/bin

C PATH=/usr/bin

D set PATH=/usr/bin

Only export PATH=/usr/bin sets and exports the variable.

If you set a variable without export, what happens?

A It is only available in the current shell

B It is deleted immediately

C It is available to child processes

D It becomes a system variable

Variables without export stay local to the current shell.

How do you list all exported variables?

A export -p

B lsenv

C showenv

D envlist

The command export -p lists all exported variables.

Can you export a variable without assigning a new value?

A Only if the variable is empty

B No, you must assign a value

C Yes, just use <code>export VARIABLE_NAME</code>

D Only in root user

You can export an existing variable by just running export VARIABLE_NAME.

Explain in your own words what the export command does and why it is useful.

Think about how programs get information from the shell.

Describe the difference between setting a variable with and without export.

Consider where the variable can be seen or used.