Method error

samples/zlib/iostream2/zstream.h:97–99

Returns the error message for the last error which occurred on the * given compressed file. errnum is set to zlib error number. If an * error occurred in the file system and not in the compression library, * errnum is set to Z_ERRNO and the application may consult errno * to get the exact error code. */

         * to get the exact error code.
         */
        const char* error(int* errnum) {
            return ::gzerror(m_fp, errnum);
        }

        gzFile fp() { return m_fp; }