Missing header files when importing a shared library with labview 8.6?

Question

Hi all,
I want to import a .dll into my .vi program but I am not able to do it...
I have created the dll  following the ni website tutorial
http://zone.ni.com/devzone/cda/tut/p/id/3303#toc2
Once the dll has been created, I have tried to import it with
Tools-Import-Shared Library(dll)
After parsing the header file appears an error like this one:
void __cdecl Zdmt(LVBoolean *stop, double P, char channelName[],
    TD1 *errorIn, TD14 *FFTOptions, TD12 *Calibration, char FileName[],
    int32_t minRecordLength, TD26 *InstrumentHandler, LVRefNum sessionRefArray[],
    LVRefNum *queueIN, TD1 *errorOut, LVBoolean *averagingDone,
    HWAVES LastRecordFetched, TD24 *Impedance, TD17 *ColeColeCluster,
    TD18 *FFTcluster, TD5 *InstrumentHandleOutputCluster, LVRefNum *queueOut,
    int32_t *Acquired, TD6 *FreqTimeInfoCluster, double *averagesCompleted,
    int32_t len);
The following symbols are not defined:
LVBoolean; int32_t; LVRefNum;
Undefined symbols can prevent the wizard from recognizing functions and parameters. To correct this problem, check the header file to determine if you must add predefined symbols. Click the Back button to return to the previous page of the wizard to add a preprocessor definitionsl (for example, "NIAPI_stdcall = __stdcall" or "NIAPIDefined = 1").
The following header file was not found in the specified header file or one of the referenced header files:
-  extcode.h
To fix, click the Back button to go to the previous page and add the header file path to the Include Paths list.
I have replaced the first line #include "extcode.h" of the dll header file for #include "C:\Program Files\National Instruments\LabVIEW 8.6\cintools\extcode.h" that is the full path where the header file is located. However, new libraries seems to be missed:
-  stdint.h
-  MacTypes.h
Does anybody know what I have to do??
Any help will be really appreciated,
Regards,
Benjamin

Answer 1

If you use any of the LabVIEW cintools headers, they reference other headers too. The import wizard is written in a way that it simply skips parsing datatypes that can not be resolved due to missing header files.  If your functions you want to import references such datatypes then you get an according error about any include files the wizard could not load, otherwise not. The wizard can not know which of the missing header files is the problem since it obviously doesn't know what would be in those header files.
The LabVIEW cintools headers are multiplatform, meaning they evaluate various compiler predefined defines to determine which platform they are included in. The import library wizard does not define any specific defines, since it is not really a compiler. So you have to define them. And they get adapted with each new LabVIEW version to support new compilers and compiler versions, so the defines described in the link in the first post do not have to be correct for cintools headers in newer LabVIEW versions.
All in all writing DLLs that interface to LabVIEW cintools headers should not be done by writing them and then importing them using the wizard but instead you should write the VI and create the Call Library Node, then let LabVIEW create a template C file from the context menu of the Call Library Node and copy that into your C sources and fill in the functions from there.
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions