diff --git a/src/winmain.c b/src/winmain.c
index e1fdf0f9b..73e7bf7eb 100644
--- a/src/winmain.c
+++ b/src/winmain.c
@@ -97,6 +97,8 @@ extern bool ft_ngdebug; /* some additional debug info printed */
 extern bool ft_batchmode;
 extern FILE *flogp;     /* definition see xmain.c, stdout redirected to file */
 
+extern void cp_doquit(void);
+
 #include "winmain.h"
 
 /* --------------------------<history management>------------------------------ */
@@ -506,11 +508,8 @@ MainWindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
         goto DEFAULT_AFTER;
 
     case WM_CLOSE:
-        /* Put Spice commmand "Quit" to end the program into the text buffer */
-        PostSpiceCommand("quit");
-
-        /* If simulation is running, set a breakpoint */
-        raise (SIGINT);
+        cp_doquit();
+        /* continue if the user declined the 'quit' command */
         return 0;
 
     case WM_SIZE: