LANGUAGE » JAVASCRIPT » NODEJS

Built-in

Last updated:
Reference:nodejs.org

Process ​

VariableDescription
process.envA object containing the user environment.
process.exitCodeExit code used when the script ends.
MethodDescription
process.exitImmediately terminates the process with the specified exit code.

Async ​

Creating an async function (returns Promise) and waiting for the result:

javascript
async function getUser() {}
const user = await getUser();

To continue the program meanwhile, use a callback:

javascript
getUser().then((user) => {});

Exit Code ​

If exiting the program due to an error, setting process.exitCode = 1 is preferred over process.exit(1) because it will wait for asynchronous code to finish, like writes to stdout. But you'll have to skip the remaining code if there is any:

javascript
if (somethingBadHappened()) {
  printStuff();
  process.exitCode = 1;
}

if (process.exitCode !== undefined) {
  // ...
}

Usually it is much easier to just raise an error that will not be catched for the same result:

javascript
if (somethingBadHappened()) {
  printStuff();
  throw new Error('Something bad happened');
}