In article <944 at ubu.warwick.UUCP> geoff at emerald.UUCP (Geoff Rimmer) writes: -#ifdef __STDC__ -#if __STDC__==0 -#undef __STDC__ -#endif -#endif I have no guarantee that the implementation will allow my program to #undef __STDC__. I suspect that some won't.