fix potential use-after-free in child process
diff -wpruN '--exclude=*.orig' a~/select.c a/select.c
--- a~/select.c	1970-01-01 00:00:00
+++ a/select.c	1970-01-01 00:00:00
@@ -83,6 +83,7 @@ select_fini(void)
 
 	free(events);
 	events = NULL;
+	nevents = 0;
 }
 
 static int