fs_pdir
error = fs_pdir(sc, fid, dirname, sizeof(dirname), &pst);
static int fs_pdir(struct fs_softc *, struct l9p_fid *, char *, size_t,
error = fs_pdir(softc, fid, newname, sizeof(newname), &st);
error = fs_pdir(sc, fid, olddir, sizeof(olddir), &opst);