Temporary set and held only in the current terminal (shell).

# 환경변수 설정
Export variable name = value

# Turn Off Environment Variables
Unset $Variable Name

# Check Environment Variables 
echo $ variable name

# Check all environment variables
export

Set Linux/Mac Permanent Configuration Variables (Permanent Settings)

• .You can set a variable name in the bashrc file or the .zshrc file and apply it permanently.

# For the shell (Bash) used by Linux
echo "export variable name=value" >> ~/.bashrc // or corresponding ~/.You can write it down directly on the bashrc file
source ~/.bashrc// apply configuration settings

# For the shell (Zsh) used by the Mac
echo "export variable name=value" >> ~/.zshrc 
source ~/.zshrc

Check the shell currently in use

• To check the shell currently in use, use the echo $SHELL command.

echo $SHELL

프로그램에서 등록된 환경변수 사용 예제

• Python:

import os # 환경변수 읽기
my_variable = os.environ.get('환경변수명')

• JavaScript (Node.js):

const myVariable = process.env.환경변수명;