The reason for that is that, for simplicity's sake, all of the I/O functions share the same error type. `UnexpectedEof` should never be returned from `read_to_

The reason for that is that, for simplicity's sake, all of the I/O functions share the same error type. `UnexpectedEof` should never be returned from `read_to_end`, but it can be returned from `read_exact`.