return out;
 }
 
+// Callback function for getting files from the database
 int populate_set( void *files_v, int, char **vals, char ** ) {
   file_set *files = reinterpret_cast<file_set*>( files_v );
   files->insert( new FileData( vals[0][0],
   for( file_set::iterator i = previous_files.begin(); i != previous_files.end(); ++i ) {
     cout << (*i)->getFileName() << endl;
   }
+
+  // Now divide the two sets into three sets (union and set differences)
+  FileDataPtrCmp cmp;
+
+  file_set new_set;
+  set_difference( current_files.begin(),  current_files.end(),
+                  previous_files.begin(), previous_files.end(),
+                  inserter( new_set, new_set.begin() ),
+                  cmp );
+
+  file_set deleted_set;
+  set_difference( previous_files.begin(), previous_files.end(),
+                  current_files.begin(),  current_files.end(),
+                  inserter( deleted_set, deleted_set.begin() ),
+                  cmp );
+
+  // previous_files *should* definitely be the first set here
+  file_set common_set;
+  set_difference( previous_files.begin(), previous_files.end(),
+                  current_files.begin(),  current_files.end(),
+                  inserter( common_set, common_set.begin() ),
+                  cmp );
 }