To show environment variables in Linux, you have several common commands:

• List all environment variables:

  • Use printenv or env to list all environment variables and their values:

    printenv
    

or

      env
      

* Since the output can be long, you can pipe it to `less` for easier reading:
      
      printenv | less

• Display a specific environment variable:

  • Use printenv followed by the variable name:

    printenv VARIABLE_NAME
    

  • Or use echo with a $ prefix:

    echo $VARIABLE_NAME
    

For example:

echo $HOME
printenv HOME

• Search for variables containing a string:

  • Use printenv or set with grep:

    printenv | grep STRING
    set | grep STRING
    

• Note on commands:

  • printenv is designed specifically for environment variables.
  • env can also list variables but is primarily used to run commands with modified environments.
  • set shows all shell variables, including environment, local, and shell functions, so its output is broader.

These methods allow you to view and manage environment variables effectively on Linux systems