--- Modules/mmapmodule.c.orig	2009-06-12 12:44:46.000000000 +0200
+++ Modules/mmapmodule.c	2009-06-12 12:44:18.000000000 +0200
@@ -158,7 +158,8 @@
 #endif /* MS_WINDOWS */

 #ifdef UNIX
-	(void) close(self->fd);
+	if (0 <= self->fd)
+		(void) close(self->fd);
 	self->fd = -1;
 	if (self->data != NULL) {
 		munmap(self->data, self->size);