diff --git a/testdata/speed_cache.tdir/makeqs.c b/testdata/speed_cache.tdir/makeqs.c
index b04a0c767..8e6179f66 100644
--- a/testdata/speed_cache.tdir/makeqs.c
+++ b/testdata/speed_cache.tdir/makeqs.c
@@ -1,5 +1,10 @@
+/**
+ * \file
+ * This file creates queries for the speed test
+ */
 #include <stdio.h>
 #include <stdlib.h>
+/** main program to create queries, pass the number of them. */
 int main(int argc, char** argv) {
         int i;
         int max = atoi(argv[1]);