Create a new patch file for each patch and close old handle

This stopped a few misbehaviours

test/manual/minimal_lib.cpp

@@ -1,10 +1,11 @@
 #include "minimal_lib.h"
+#include <cstdio>
 
 namespace minimal_lib {
 
 int getNewValue(int x) {
   static int value = 0;
-  value = value + 5;
+  value = value + x;
   return value;
 }