Z_SYNC_FLUSH
ret = zlib_inflate(inflate, Z_SYNC_FLUSH);
ret = zlib_deflate(&workspace->strm, Z_SYNC_FLUSH);
zerr = zlib_inflate(&strm->z, Z_SYNC_FLUSH);
zerr = zlib_inflate(&stream, Z_SYNC_FLUSH);
zlib_err = zlib_inflate(stream, Z_SYNC_FLUSH);