void set_bool(void *v, const char *arg) { char *p = (char *)v; int f = get_false_true(arg); *p = -1 == f ? 0 == *p : 0 != f; }
void set_bool(bool *v, const char *arg) { int f = get_false_true(arg); *v = -1 == f ? false == *v : f; }