A VIX error is a 64-bit value. A value of VIX_OK indicates success, but otherwise (if there is an error), several bit regions in the 64-bit value might be set. The least significant 16 bits are set to the error code described for VIX errors. More significant bit fields might be set to other values.
As for the VIX API, use the macro VIX_ERROR_CODE(err) to mask off bit fields not used by the VDDK.
