sbool filesHaveSameContents(File a, File b) ctex {
  long n = fileSize(a);
  if (fileSize(b) != n) false;
  
  temp InputStream is1 = newBufferedInputStream(a);
  temp InputStream is2 = newBufferedInputStream(b);
  
  int data;
  while ping ((data = is1.read()) != -1)
    if (data != is2.read()) false;

  true;
}