- The process object is a global object and can be accessed from anywhere. It is an instance of EventEmitter.
Exit Codes
https://nodejs.org/api/process.html#process_exit_codes
Signal Events
https://nodejs.org/api/process.html#process_signal_events
process.env
https://nodejs.org/api/process.html#process_process_env
process.exit([code])
https://nodejs.org/api/process.html#process_process_exit_code
- codeが省略されたら'success'(0)
'failure' codeでexitしたい
process.exit(1);