rc, err = OpenReader(path)
		if err == nil {
			defer rc.Close()
			z = &rc.Reader
		}
		var err2 error
		raw, err2 = os.ReadFile(path)
		if err2 != nil {
			t.Errorf("ReadFile(%s) error=%v", path, err2)
			return
		}
	}
	if err != zt.Error {
		t.Errorf("error=%v, want %v", err, zt.Error)
		return
	}

	// bail if file is not zip
	if err == ErrFormat {
		return
	}

	vectors := []struct {
		file    string    // Test input file
		headers []*Header // Expected output headers
		chksums []string  // MD5 checksum of files, leave as nil if not checked
		err     error     // Expected error to occur
	}{{
		file: "testdata/gnu.tar",
		headers: []*Header{{
			Name:     "small.txt",
			Mode:     0640,
			Uid:      73025,
			Gid:      5000,
			Size:     5,

	}

	for i, tt := range tests {
		pos, err := r.Seek(tt.off, tt.seek)
		if err == nil && tt.seekerr != "" {
			t.Errorf("%d. want seek error %q", i, tt.seekerr)
			continue
		}
		if err != nil && err.Error() != tt.seekerr {
			t.Errorf("%d. seek error = %q; want %q", i, err.Error(), tt.seekerr)
			continue
		}
		if tt.wantpos != 0 && tt.wantpos != pos {
			t.Errorf("%d. pos = %d, want %d", i, pos, tt.wantpos)
		}