code: function readFromSnapshotSub (entityContent, dock, buffer, offset, length, position, cb) {
      var p;
      if ((position !== null) && (position !== undefined)) {
        p = position;
      } else {
        p = dock.position;
      }
      if (cb) {
        payloadCopyUni(entityContent, buffer, offset, p, p + length, function (error, bytesRead, buffer2) {
          if (error) return cb(error);
          dock.position = p + bytesRead;
          cb(null, bytesRead, buffer2);
        });
      } else {
        var bytesRead = payloadCopyUni(entityContent, buffer, offset, p, p + length);
        dock.position = p + bytesRead;
        return bytesRead;
      }
    }
docs: /////////////////////////////////////////////////////////////// read ////////////////////////////////////////////////////////// ///////////////////////////////////////////////////////////////