setifname
DEF_CMD_ARG("name", setifname),
wf->base.setifname = ath_setifname;
void (*setifname)(struct athstatfoo *, const char *ifname);
wf->setifname(wf, optarg);
wf->setifname(wf, optarg);
wf->base.setifname = wlan_setifname;
void (*setifname)(struct wlanstatfoo *, const char *ifname);