C program calling dll made in Labview7.1

Hi all
i made a program in labview and the made its DLL using application builder.Now when i want to use the DLL in C program,my program is compling but while building it the error comming is Unresolved external '_SETINS' referenced from D:\dhiraj\labread.OBJ. SETINS is the function name i am calling.
Moreover i also want to know that is there someway to provide character string output from the DLL made in Labview.
Also if the parameter which i am passing as arguments to the DLL and then in DLL i am changing the argument value,then when i come back after the DLL call ,what will be the value of the arguments??.Will it change or remain the same.
Thanks in Advance for early reply.....
Dhiraj Kumar

dhiraj03416 wrote:
Hey Why is someone not attending to my problem,maybe i feel labview DLL's can't be used in any language.Its not being recognized by the C++.
Oky let me make it simple.
Let us make a DLL with C=SUM(A,B) where (C=A+B)
now how to use the DLL in any orther language and use the function SUM.
Hoping This time someone replies
Thanks in Advance
Dhiraj Kumar
When you build your DLL in LabVIEW, LabVIEW also creates a .h file and a .lib file. The H file you obviously have figured out already needs to be #included in your source file where you want to call the function. This allows the compiler to create code to call that function correctly. However the linker has no idea where to get that function from and that is where the .lib file comes into the play. You need to add that lib file to your project too, so the linker can resolve the function call properly.
A little bit of C programming basics also includes some basic knowledge about linking the program together and that you need to have all functions available in either an object or library file, somewhere
And last but not least the lib file only contains the code to look for the function in the according DLL file, so in order to run your application afterwards you need to make sure to copy (and distribute) the DLL into your executable directory.
Message Edited by rolfk on 10-30-2009 01:32 PM
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions

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> Thanks for the information Greg. There is no documentation on this
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>
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The problem about call dll from VB....

Dear All.
I have a device and VB dll file.I want to use labview to call dll.But Labview show "An Exception occurred within the external code ..."
Below is to call this dll details.
1、FindHardware：
Call it at beginning when load program first, it can let program auto detect printer port address and model of dso scope.
parament
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UIP: open UIP(2048) array
UCP:open UCP(1023, 1023 + 11, 6) array
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board_model：
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Then is my program
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Attachment file is this dll.
http://us.f1.yahoofs.com/bc/500cf3ac/bc/dll/dll.rar?bfd1QSDBkHPgKI9c
Thanks.
由 Samyang 在 10-09-2005 07:14 AM 上編輯的訊息

I can't say I understand the documentation snippet you provides, and I also can't access the DLL, but here are a couple things...
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2. You have the winversion being passed by pointer, but the docs make it look like a regular integer. Is that correct?
3. Your board model is being passed by value, but it is listed as a return value in the docs. That would indicate an actual return value or a parameter passed by reference.
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http://detritus.blogs.com/lycangeek

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See
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1097 error calling DLL

Hi,
I am a student currently doing an internship, and I may need some help. First of all, I am a beginner with LabVIEW, so maybe what I am asking is silly but I am completly lost.
In my project, I have to command a CD/DVD reader manually (speed of rotation, data transmitted...), and for this I am using a free DLL file I find download on this website.
http://www.frogaspi.org/
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As I understand in several posts on this forum, the reason is probably that the buffer used by the Call Library Node is not correctly sized. Indeed, the parameter is a pointer to a cluster that contains numbers and strings. But how exactly can I do a allocation of memory on Labview?
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The header file and the DLL files are available on the link I post (it is not my work so I am a little uncomfortable posting it here)
Thanks a millions,

Hi,
First of all, thanks for your answer. Sorry for answering just now, but I was trying to advance by my own too, and also I was asked to work on other things in my internship. I will try to explain you what I have done so far.
Thanks for explaining me the difference between an API and an ASPI, I have to recognize that I did not get the difference between both before you told me, and that makes everythink clearer to me now. Still, the "dll" I find on this website seems to be a ASPI Manager, and they say
"The ASPI Manager for the SCSI host adapter processes these function calls and generates the appropriate SCSI commands to the SCSI peripherals".
So, maybe I misunderstand that again, but it seems to me that the first step you recommend to do is already done by the creater of this DLL.
Also, I am now using Labview 2011 instead of 2010, but I don't think this change a lot in my problem. I send the labview code I made, it is currently very basic but if I cannot access the basic function of the DLL, there is just no point trying to make a code more complicated. I am for now just trying to call one of the function of the DLL and see what is happening.
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typedef struct
BYTE SRB_Cmd;                 // ASPI command code = SC_HA_INQUIRY
BYTE SRB_Status;              // ASPI command status byte
BYTE SRB_HaId;                 // ASPI host adapter number
BYTE SRB_Flags;               // Reserved, MUST = 0
DWORD SRB_Hdr_Rsvd;     // Reserved, MUST = 0
BYTE HA_Count;                // Number of host adapters present
BYTE HA_SCSI_ID;            // SCSI ID of host adapter
BYTE HA_ManagerId[16];    // String describing the manager
BYTE HA_Identifier[16];      // String describing the host adapter
BYTE HA_Unique[16];         // Host Adapter Unique parameters
WORD HA_Rsvd1;             // Reserved, MUST = 0
SRB_HAInquiry, *PSRB_HAInquiry;
It is not really working so as I read on this NI webpage: http://digital.ni.com/public.nsf/allkb/DCB90714981A1F148625731E00797C33
"Note that if your complex data type is a struct with more than primitive data types (int, double, char), it is easiest to create a wrapper DLL from a C-based language."
So this is what I have been trying to do, and maybe it is very basic, but if anyone could send me a link on how to create a wrapper DLL, it would be very useful. I already download the one National Instrument made, but I did not really understand it.
The DLL seems to work fine as I manage to call it from a C console programme. (I send the code too). But I tried to followed some tutorials but I just cannot create a DLL that I could use, so maybe there is something badly set in my IDE (I am using Code::Blocks). So if anybody has any idea of what is going on I would be very grateful. Again, the DLL I tried to make is very basic but if the basic are not ok, there is no point going further.
This is what is happening right now : I create the dll file following the instruction but when I compile I get this warning:
"warning: 'int addition(int, int)' redeclared without dllimport attribute: previous dllimport ignored"
and then I just can't compile the test programm because I get the error: altough I did set the file.a as a linker.
"undefined reference to `_imp__addition' "
I send the compressed files that I made, I think there should be everything that is needed to answer me, except the DLL file that is available here http://www.frogaspi.org/download.htm
Again sorry, but the owner of this library explicitly asked not to purpose a local download so I feel very unconfortable doing that, so please, just click on the link and download it from there.
I do not know if anybody has ever done what I am trying to do, and I am not asking for someone to do it instead of me, I am sorry if I sound like it in my previous message, this was definitly not my intention.
Still, the problem of having to write a wrapper seems to be a commun issue for people calling DLL in Labview, and I didn't find answer very clear on how to create a dll. I guess I could eventually find out by myself, but if anybody can help, that would make me save a lot of time.
Maybe what I am asking is very easy, but again my knowledge about C language is basic, I am not a computer science student so...
Anyway, thank in advance,
Adrien
Attachments:
Problem Wrapper.zip ‏31 KB

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Bye, Olaf.
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> In order to call dll's functions in a program, written in graphical
> programming langage (labview), I would like to understand the arguments
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>
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>
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Why do I get 'Bad Calling Dll Convention' ?

Hi,
the attached fiel contains an experimen to read dll made in LV 8.6 and use it in VB6.
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Attachments:
LVDLL Experiment.zip ‏23 KB

Rafi,
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' void AddNumbers(double x, double y, char string[], double *xY, char concatenatedString[], int32_t len)
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Jason

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>
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>
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#Date: Fr, 16. Sep 2011 16:25:25
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File Unknown(0) : Crash: Crash caught by NIER
minidump id: 8a779b3f-51d7-4864-8e4d-6ab0195cd158
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error.PNG ‏11 KB

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