Using CHANNEL_PRINTS to transfer printbuffers to stdout is now working.

luprex/cpp/core/enginewrapper.hpp

@@ -115,6 +115,11 @@ struct EngineWrapper {
     //
     double (*get_clock)(EngineWrapper *w);
 
+    // Check the 'have prints' flag.  If true, then the engine
+    // wants the driver to use CHANNEL_PRINTS to obtain prints.
+    //
+    bool (*get_have_prints)(EngineWrapper *w);
+
     // Check the 'rescan_lua_source' flag.  If this flag is set, it means
     // that the engine wants the driver to rescan the lua source code.
     // When the driver sees this flag, it should rescan the source and call