The export command in shell scripting is used to mark environment variables to be passed to child processes. This is crucial for configuring the environment in which your programs run.

Understanding Shell Attributes

When you use export without any arguments, it displays all the environment variables that are currently set in your shell session. These variables include system-defined ones and those you have defined yourself.

# To show current shell attributes:
export

Exporting Custom Environment Variables

To make a variable available to child processes, you need to export it. This is typically done by assigning a value to the variable and then exporting it.

# To export an environment variable:
export VARNAME="value"

Example: Setting a Custom Path

You might want to add a custom directory to your system's PATH variable so that executables in that directory can be run from anywhere.

export PATH=$PATH:/path/to/your/custom/bin

Example: Setting Configuration Variables

Many applications use environment variables for configuration. For instance, setting an API key:

export API_KEY="your_secret_api_key_here"

Benefits of Using Export

Using export ensures that your application or script has access to necessary configurations and settings without hardcoding them directly into the code. This promotes flexibility and security, especially for sensitive information like API keys or database credentials.

Further Reading

• MDN Web Docs - export statement (JavaScript context, for understanding module exports)
• Bash Manual - The export builtin