getfmt
wf->setfmt(wf, getfmt(optarg));
wf = athaggrstats_new(ifname, getfmt("default"));
wf->setfmt(wf, getfmt(optarg));
wf = athstats_new(ifname, getfmt("default"));
wf = npestats_new(ifname, getfmt("default"));
wf->setfmt(wf, getfmt(optarg));
wf = wlanstat_new(ifname, getfmt("default"));
wf->setfmt(wf, getfmt(optarg));