function processReallyExit (code) {
  process.exitCode = code || 0
  emit('exit', process.exitCode, null)
  /* istanbul ignore next */
  emit('afterexit', process.exitCode, null)
  /* istanbul ignore next */
  originalProcessReallyExit.call(process, process.exitCode)
}
Convert array of 16 byte values to UUID string format of the form:
XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX