diff --git a/Modules/_tkinter.c b/Modules/_tkinter.c
index 83f9be5..bbada35 100644
--- a/Modules/_tkinter.c
+++ b/Modules/_tkinter.c
@@ -30,7 +30,7 @@
 #include <tcl.h>
 #include <tk.h>
 
-extern char *getprogramname ();
+extern char *Py_GetProgramName ();
 
 /* Internal declarations from tkInt.h.  */
 #if (TK_MAJOR_VERSION*1000 + TK_MINOR_VERSION) >= 4001
@@ -1234,11 +1234,11 @@
   char *className = NULL;
   int interactive = 0;
 
-  baseName = strrchr (getprogramname (), '/');
+  baseName = strrchr (Py_GetProgramName (), '/');
   if (baseName != NULL)
     baseName++;
   else
-    baseName = getprogramname ();
+    baseName = Py_GetProgramName ();
   className = "Tk";
   
   if (!PyArg_ParseTuple (args, "|zssi",