pointer to struct in call library function

[Flavia]

I have a dll function with this prototype:
DWORD CAN_Read(TPCANMsg* pMsgBuff);
where TPCANMsg is a structure.
typedef struct{
DWORD ID;
BYTE MSGTYPE;
BYTE LEN;
BYTE DATA[8];
}TPCANMsg;
I create a cluster that is represented as a structure. But in Call Library Function witch do I have to choose: "Handles by Value" or "Pointers to Handles"?

[JRA]

If you are calling the function above, you will need to use Pointers to Handles because this particular function is using a pass by reference variable (pointer) to send the TPCANMsg datatype.

[Greg_McKaskle2]

> I have a dll function with this prototype:
> DWORD CAN_Read(TPCANMsg* pMsgBuff);
> where TPCANMsg is a structure.
> typedef struct{
> DWORD ID;
> BYTE MSGTYPE;
> BYTE LEN;
> BYTE DATA[8];
> }TPCANMsg;
> I create a cluster that is represented as a structure. But in Call
> Library Function witch do I have to choose: "Handles by Value" or
> "Pointers to Handles"?

The key is to make sure the type is set to Adapt. The setting of the
Data Format shouldn't matter since your datatype doesn't have a string,
array, path, or other nonflat data element.

for the DATA[8], you will want to use eight inline U8s, or a cluster of
the bytes.

The info I'm going on is the LV External Code manual.

Greg Mckaskle

[Flavia]

Thank you so much for this answer. It really helped me.
Flavia

[Flavia]

Thank you so much for your answer. I did what you said and it worked very well.
Flavia