Shell Bash Check if Environment Exist

Your provided code snippet appears to be a Bash script that checks if the TARGET_PATH environment variable is empty and, if so, sets it to ~/go by appending an export statement to the .bashrc file. This is a common technique to ensure that environment variables are set with default values if they are not already defined.

Here’s a breakdown of what the code does:

1. if [[ -z "${TARGET_PATH}" ]]; then: This line checks if the TARGET_PATH environment variable is empty (i.e., its value is not set). The -z flag is used to test if a string is empty.

2. If the TARGET_PATH is empty, the script proceeds to the next line.

3. echo 'export TARGET_PATH=~/go' >> .bashrc: This line appends the export statement export TARGET_PATH=~/go to the .bashrc file. This effectively sets the TARGET_PATH environment variable to ~/go when the user’s shell session starts.

This code is useful for ensuring that the TARGET_PATH environment variable is always defined with a default value when a user’s shell session starts. It’s commonly used to set default values for environment variables, making it easier to work with scripts and programs that depend on them.

Keep in mind that modifying the .bashrc file will affect the behavior of the user’s shell session. Ensure that this is the desired behavior for your use case and that users are aware of the changes to their environment variables.