FLDFget_node_null_data, FLDFset_node_null_data, FLDFset_node_null_flag
Synopsis
get/set the NULL data flag and NULL data value in one Node_Data component
INTEGER FLDFget_node_null_data (field, comp, null_flag, null_value)
INTEGER field(OIDSIZ)
INTEGER comp
INTEGER null_flag
INTEGER null_value
INTEGER FLDFset_node_null_data (field, comp, null_flag, null_value)
INTEGER field(OIDSIZ)
INTEGER comp
INTEGER null_value
INTEGER type
INTEGER FLDFset_node_null_flag (field, comp, null_flag)
INTEGER field(OIDSIZ)
INTEGER comp
INTEGER null_flag
Description
These routines get/set the NULL data flag (null_flag) in a Node_Data Data_Array that indicates the presence of NULL data. They also get/set the data value (null_value) that should be interpreted as meaning "no data here."
Parameters
field
The integer id of a field that contains a Node_Data subobject.
comp
An integer that sets which component [0-n] of the Node_Data to get/set.
null_flag
In FLDFget_node_null_data, an integer that signifies "NULL data is present" is returned. In FLDFset_node_null_flag, this sets null_flag within the Data_Array. By AVS/Express convention, 0 means there is no NULL data. Any other value means there is NULL data.
null_value
In FLDFget_node_null_data, an integer representing a pointer to a data item of unknown type in which the null data value this component is using will be returned.
In FLDFset_node_null_data, an integer representing a pointer to a data item of unknown type from which the null data value will be copied into the component.
type
FLDFset_node_null_data only. An integer that specifies the type of the null_value. This should match the primitive data type of the rest of the Data_Array. The choices are (defined in avs/om.h):
Constant
|
Value
|
DTYPE_CHAR |
0 |
DTYPE_BYTE |
1 |
DTYPE_SHORT |
2 |
DTYPE_INTEGER |
3 |
DTYPE_FLOAT |
4 |
DTYPE_DOUBLE |
5 |
DTYPE_UNSET |
DNTYPES+1 |