Added vreplay with stdout

luprex/core/cpp/driver-util.hpp

@@ -96,6 +96,7 @@ private:
     Status status_;
     std::string logfn_;
     std::string engine_;
+    bool enable_stdout_;
     
     void set_status(Status e);
 
@@ -119,6 +120,15 @@ public:
     //
     bool open_logfile(const char *fn);
 
+    // Enable stdout.
+    //
+    // Normally, stdout is suppressed during replay.
+    // If you enable stdout, then the engine will print
+    // all the same messages it did when running in the
+    // first place.
+    //
+    void enable_stdout() { enable_stdout_ = true; }
+
     // Execute a single step from the replay log.
     //
     // Returns a status code, which is usually ST_REPLAYING.