struct value_pair posval[PARSE_MAX_VP];/* possible values */
const char *parent; /* parent option */
int hide; /* hide if parent isn't set */
+ int hide_on_set; /* hide on set, not on unset */
const char *inverse; /* if set, apply opposite action to this option */
struct fio_option *inv_opt; /* cached lookup */
int (*verify)(struct fio_option *, void *);