extern uschar *expand_string(uschar *);
extern uschar *expand_string_copy(uschar *);
extern int_eximarith_t expand_string_integer(uschar *, BOOL);
+extern void modify_variable(uschar *, void *);
extern int filter_interpret(uschar *, int, address_item **, uschar **);
extern BOOL filter_personal(string_item *, BOOL);