inflateSync
ZEXTERN int ZEXPORT inflateSync(z_streamp strm);
err = inflateSync(&d_stream); /* but skip the damaged part */
ret = inflateSync(&strm); assert(ret == Z_DATA_ERROR);
ret = inflateSync(&strm); assert(ret == Z_OK);
ZEXTERN int ZEXPORT inflateSync(z_streamp strm);