/** Create a digest for a file
* @param filename File name
- * @param progress Optional progress reporting function. The function will be called
- * with a progress value between 0 and 1
+ * @param progress Optional progress reporting function, called with a number of bytes done
+ * and a total number of bytes.
* @return Digest
*/
-extern std::string make_digest (boost::filesystem::path filename, boost::function<void (float)>);
+extern std::string make_digest(boost::filesystem::path filename, boost::function<void (int64_t, int64_t)>);
extern std::string make_digest (ArrayData data);