/** writes safely (to temp file, then rename) */

public static byte[] saveBinaryFile(String fileName, byte[] contents) ctex {

  File file = new File(fileName);

  File parentFile = file.getParentFile();

  if (parentFile != null)

    parentFile.mkdirs();

  String tempFileName = fileName + "_temp";

  try (FileOutputStream fileOutputStream = newFileOutputStream(tempFileName)) {

    fileOutputStream.write(contents);

  }

  if (file.exists() && !file.delete())

    throw new IOException("Can't delete " + fileName);

  if (!new File(tempFileName).renameTo(file))

    throw new IOException("Can't rename " + tempFileName + " to " + fileName);

  ifndef LeanMode

  vmBus_send('wroteFile, file);

  endifndef

  ret contents;

}

static byte[] saveBinaryFile(File fileName, byte[] contents) {

  ret saveBinaryFile(fileName.getPath(), contents);

}