an_read_bap
if (an_read_bap(sc, fid, 0, &frmhdr, sizeof(frmhdr)) != 0) {
static int an_read_bap(struct an_softc *, int, int, void *, int);
an_read_bap(sc, fid, -1, gap, gaplen + sizeof(u_int16_t));
an_read_bap(sc, fid, -1,
error = an_read_bap(sc, rid, 0, &len, sizeof(len));
return an_read_bap(sc, rid, sizeof(len), buf, len);