Read up to _length_ bytes directly from the underlying stream without
decompressing. Bypasses BGZF blocking, so must be used with care in
specialised circumstances only.
@param fp BGZF file handler
@param data data array to read into
@param length number of raw bytes to read
@return number of bytes actually read; 0 on end-of-file and -1 on error
Read up to _length_ bytes directly from the underlying stream without decompressing. Bypasses BGZF blocking, so must be used with care in specialised circumstances only.
@param fp BGZF file handler @param data data array to read into @param length number of raw bytes to read @return number of bytes actually read; 0 on end-of-file and -1 on error