A file abstraction for sequential writing.
The implementation must provide buffering since callers may append small fragments at a time to the file.
tensorflow::WritableFile::WritableFile()virtual tensorflow::WritableFile::~WritableFile()virtual Status tensorflow::WritableFile::Append(const StringPiece &data)=0virtual Status tensorflow::WritableFile::Close()=0virtual Status tensorflow::WritableFile::Flush()=0virtual Status tensorflow::WritableFile::Sync()=0