// If we are not waiting for shutdown, then there is no exit code to check.
if (!waitpid) {
    return 0;
}
if (allowedExitCode !== returnCode) {
    throw new MongoRunner.StopError(returnCode);
} else if (returnCode !== MongoRunner.EXIT_CLEAN) {
    print("MongoDB process on port " + port + " intentionally exited with error code ",
          returnCode);
}