#define PRISM2_HOSTAPD_MAX_BUF_SIZE 1024
#define PRISM2_HOSTAPD_GENERIC_ELEMENT_HDR_LEN \
-((int) (&((struct prism2_hostapd_param *) 0)->u.generic_elem.data))
+ offsetof(struct prism2_hostapd_param, u.generic_elem.data)
/* Maximum length for algorithm names (-1 for nul termination)
* used in ioctl() */