func (a *hdbAccessor) ReadAt(b []byte, off int64) (n int, err error) {
	return a.accessor.ReadAt(b, off+a.delta)
}
Implementation of storage.Accessor
package zdb
import (
	"bytes"
	"fmt"
	"github.com/cznic/fileutil/hdb"
	"github.com/cznic/fileutil/storage"
	"os"
	"path"
	"runtime"
	"strconv"
)
type hdbAccessor struct {
	delta    int64
	accessor storage.Accessor
}
func (a *hdbAccessor) Close() error {
	e1 := a.accessor.Sync()
	e2 := a.accessor.Close()
	if e1 != nil {
		return e1
	}
	return e2
}
func (a *hdbAccessor) Name() string {
	return a.accessor.Name()
}