Creating a DLL in LabVIEW containing a function using pointer to pointer

Hi!
I´m facing the problem to create a DLL from LabVIEW containing the following C-function:
functionF(structS** arrayA) ,
where:
structS is a struct of various data-types (e.g. int)
arrayA is an C-array of structS
How can this be done? Any ideas?
Thank you in advance for your support

This cannot be done in LabVIEW. LV doesn't have the data type "Pointer" as C has.
The only workaround I can think of is to use an array of strings in LV and in the interface define the parameter as "by reference". In LV you have to typecast the wire with the string to a cluster withthe layout of structS.
As far as I know an array of strings is represented as an array of pointer to strings. This is because strings are variable in length and therefore LV uses this method storing the pointers to the strings in the array and not the elements as usual.
You have to read the document about memory and data types of LabVIEW. In elder versions this was in the LabVIEW Bookshelf but I haven't found it in short in the newer version.
Waldemar
Using 7.1.1, 8.5.1, 8.6.1, 2009 on XP and RT
Don't forget to give Kudos to good answers and/or questions

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>
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=========================================
Please remember to accept a solutions and show your appreciation by giving Kudos to helpful messages...
Mangesh D.
CLAD | Project Engineer
==
VIPM, LabVIEW 8.2, 2009, 2011SP1, 2012, 2012SP1, 2013, cRIO,cDAQ, PXI, ELVIS, Multisim, Smart Camera....
Solved!
Go to Solution.

ManLD wrote:
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VCORE (1<<0)
V25 (1<<1)
V33 (1<<2)
V50 (1<<3)
V120 (1<<4)
VSB (1<<5)
VBAT (1<<6)
VN50 (1<<7)
VN120 (1<<8)
VTT (1<<9)
retval
[out]Point to a variable in which this function returns the voltage in Volt.
Typesupport
[out]
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Return Value
TRUE (1) indicates success; FALSE (0) indicates failure.
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Call the function first with a non-NULL typesupport to know the available fan sensors and a following call to get the voltage required.
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Message Edited by Karissa on 03-03-2010 09:05 PM
Systems Test Engineer
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Attachments:
RL5000.h ‏1 KB

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news:[email protected]..
> I see...
>
> After doing some research, it seems to me that there is no easy way to
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>
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>
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>
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Build a DLL in LabVIEW & Use the DLL in LabVIEW

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Array1D.zip ‏60 KB

At first I kept scratching my head wondering why someone would want to do this. Create a DLL in LabVIEW to call it from LabVIEW. Seems redundant. But, perhaps it's an exercise or perhaps it's for testing the DLL...
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Message Edited by smercurio_fc on 03-16-2007 12:57 PM
Attachments:
Example_BD.png ‏2 KB

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#define __PowerSupplies_H__
#ifdef __cplusplus
extern "C" {
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//==============================================================================
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#include "cvidef.h"
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/************** Global Variable Declarations **************/
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Thanks!

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Creating a DLL in LabVIEW containing a function using pointer to pointer

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