detect output redirection on windows

src/main.cpp

@@ -52,8 +52,16 @@ IMPLEMENT_APP(MSE)
 /// Write a message to the console if it is available, and to a message box otherwise
 void write_stdout(const String& str) {
 	bool have_console = false;
-	#ifndef __WXMSW__
+	#ifdef __WXMSW__
 		// somehow detect whether to use console output
+		// GetStdHandle sometimes returns an invalid handle instead of INVALID_HANDLE_VALUE
+		// check with GetHandleInformation
+		HANDLE h = GetStdHandle(STD_OUTPUT_HANDLE);
+		DWORD flags;
+		bool ok = GetHandleInformation(h,&flags);
+		if (ok) have_console = true;
+	#elif __WXGTK__
+		have_console = true; // always use console on *nix (?)
 	#endif
 	if (have_console) {
 		wxFileOutputStream file(wxFile::fd_stdout);