Interface dll function with struct in LabVIEW

Question

Hello,
I have a function:
HPDF_SetInfoDateAttr  (HPDF_Doc pdf, HPDF_InfoType type, HPDF_Date value) 
The problem is in the last input, HPDF_Date value. HPDF_Date is a struct which looks as followed:
typedef  struct  _HPDF_Date {
    HPDF_INT    year;
    HPDF_INT    month;
    HPDF_INT    day;
    HPDF_INT    hour;
    HPDF_INT    minutes;
    HPDF_INT    seconds;
    char        ind;
    HPDF_INT    off_hour;
    HPDF_INT    off_minutes;
} HPDF_Date;
Now I created the following cluster in LabVIEW:
In the Call Library VI I set the type to "Adapt to type" and tried the dataformats. However none of them worked. Can any one explain to me why the cluster is not accepted by the function? I know the error is there because the error function of the dll says that I input an invalid datetime format.
The datetime format may look like this:
Member
Effective values
year
month
Between 1 and 12.
day
Between 1 and 28, 29, 30, or 31. (Depends on the month.)
hour
0 to 23
minutes
0 to 59
seconds
0 to 59
ind
Relationship of local time to Universal Time (" ", +, −, or Z).
off_hour
If "ind" is not space, 0 to 23 is valid. Otherwise, ignored.
off_minutes
If "ind" is not space, 0 to 59 is valid. Otherwise, ignored.
Solved!
Go to Solution.

Answer 1

Actually LabVIEW can. A struct passed by value is simply pushed element for element onto the stack. So instead of defining a structure to pass as a single parameter to the CLN, you configure the CLN to take one parameter per structure element (and use the right datatype of course).
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions