void _opt_register(const char *names, enum opt_type type,
char *(*cb)(void *arg),
char *(*cb_arg)(const char *optarg, void *arg),
- void (*show)(char *buf, size_t len, const void *arg),
+ bool (*show)(char *buf, size_t len, const void *arg),
const void *arg, const char *desc)
{
struct opt_table opt;