NewExactReadCloser returns a ReadCloser that returns errors if the underlying reader does not read back exactly the requested number of bytes.

NewLimitedBufferReader returns a reader that reads from the given reader but limits the amount of data returned to at most n bytes.

NewPageWriter creates a new PageWriter.

WriteAndSyncFile behaves just like ioutil.WriteFile in the standard library, but calls Sync before closing the file.

PageWriter implements the io.Writer interface so that writes will either be in page chunks or from flushing.

ReaderAndCloser implements io.ReadCloser interface by combining reader and closer together.