docs: private final void writeMagic()
      throws LockFile.FileSecurityException,
             LockFile.UnexpectedEndOfFileException,
             LockFile.UnexpectedFileIOException {
  
          try {
              raf.seek(0);
              raf.write(MAGIC);
          } catch (SecurityException ex) {
              throw new FileSecurityException(this, "writeMagic", ex);
          } catch (EOFException ex) {
              throw new UnexpectedEndOfFileException(this, "writeMagic", ex);
          } catch (IOException ex) {
              throw new UnexpectedFileIOException(this, "writeMagic", ex);
          }
      }