Function shutdown

examples/ts-react-native-chat/scripts/dev.mjs:319–326

(exitCode = 0)

  let shuttingDown = false

  function shutdown(exitCode = 0) {
    if (shuttingDown) return
    shuttingDown = true
    for (const child of children) {
      killProcess(child)
    }
    process.exitCode = exitCode
  }

  for (const child of children) {
    child.on('error', (error) => {