How do you correctly set an exit code from a Node.js CLI script to signal success or failure to the calling shell or CI pipeline?

process.exitCode = n sets the exit code the process will use once it naturally finishes all pending work, without abruptly terminating the process (letting any pending I/O, like a final console.log flush, complete first); process.exit(n) forces immediate termination with that code, which can risk truncating unflushed output if called too early -- setting process.exitCode is generally the safer, more correct approach, with process.exit() reserved for cases needing genuinely immediate termination.

async function main() {
  try {
    await runTask();
    process.exitCode = 0; // success, but lets the process exit naturally
  } catch (err) {
    console.error(err.message);
    process.exitCode = 1; // signals failure to the calling shell/CI without forcing an abrupt exit
  }
}
main();